Electrical Issues: Hatch Lift - Battletech Pod - Tail Gate Lift Motor

[kahlid74]

So I'll post at some point my progress on the Battletech Pod but one of the things I was looking at as I have fun with this project is an automated Hatch.  As I started diving deeper I found Boat hatch lifts but they were in the $200-400 range which I didn't want to spend.  I visited some local junkyards and came across a 2007 Honda Odyssey Touring Power Tail Gate Lift Motor fully intact with all parts and working when removed for $40 bucks.

So now my question comes down to wiring/powering/intelligence required to utilize.  It's got two hook ups.  One that connects directly to the motor and one that looks like it goes to a control engine of some sort.  I'm guessing 12volt (since it's a car part) and maybe 5-10 amps to make the motor work.  So my next question comes down on how to identify the control engine and how to make it actually work.

Anyone have any thoughts?  Any EE's have an idea how to reverse engineer it?

[kahlid74]

It looks like one of the harnesses goes to the motor and the other to the electromagnetic clutch.  Any thoughts/help is greatly appreciated.  Here's some pictures:

[HaRuMaN]

Hmm.  That's interesting.  I'm guessing you would have to power the clutch to engage it, then power the motor to move the lift.  Not sure why they designed it that way, though.

[kahlid74]

Hmm.  That's interesting.  I'm guessing you would have to power the clutch to engage it, then power the motor to move the lift.  Not sure why they designed it that way, though.

I was talking with my car friend and as we talked about it we came to some idea of what we thought maybe it was doing.  The idea being any hindrance observed the clutch reverses the movement.  So if the motor was closing and closes on something it stops and then reverses.

So my big challange would be to identify whether it's just a straight up dumb on/off to the clutch/motor or whether there is some other intelligence going on.

[lilshawn]

the clutch locks the motor in it's current position. you must energize the clutch to release the motor.

it's normal operation would be to engage the clutch/motor and open the liftgate or door. once it's finished the motor and clutch disengage and the door is locked open... to close, they reverse to polarity of the motor and engage the clutch...the door closes.

this is designed this way so the door/hatch doesn't slowly close after the power is removed from the motor due to the weight of the door.

[kahlid74]

the clutch locks the motor in it's current position. you must energize the clutch to release the motor.

it's normal operation would be to engage the clutch/motor and open the liftgate or door. once it's finished the motor and clutch disengage and the door is locked open... to close, they reverse to polarity of the motor and engage the clutch...the door closes.

this is designed this way so the door/hatch doesn't slowly close after the power is removed from the motor due to the weight of the door.

That makes even more sense as the clutch arm has teeth almost like a rack and pinion setup.  I found a link that has all the electrical harness information for the Odyssey 2007 touring so I have printouts of the harness so now to wire.

So I would need +/- for both the clutch and the motor.  Then i would need another line to the motor to tell it what direction/polarity right?  What would I then send to the clutch?  An engage/disengage?  Would I send direction to the clutch as well?

Here's what I believe is the wiring harness:

[BadMouth]

It sounds like there is a real danger of getting locked inside this pod. 

[lilshawn]

It sounds like there is a real danger of getting locked inside this pod. 

LOL no doubt!

in all seriousness, there looks to be enough wires there that the limit switches are built into the motor drive assy. the pinout there isn't much help now is it.

the clutch is a give in, so no problems there. 2 wires, bam.

going to have to get out the old voltmeter and look for a couple of wires (heavier gauge probably) that attach to the motor.

[kahlid74]

It sounds like there is a real danger of getting locked inside this pod. 

LOL no doubt!

in all seriousness, there looks to be enough wires there that the limit switches are built into the motor drive assy. the pinout there isn't much help now is it.

the clutch is a give in, so no problems there. 2 wires, bam.

going to have to get out the old voltmeter and look for a couple of wires (heavier gauge probably) that attach to the motor.

Copy that.  What do I look for specifically?  Is there a voltage amount in resistance I'm looking for?  I'm familiar with the voltmeter but not 100% so I'm not entirely sure how I see what a pin does on a motor when hooking up the voltmeter.

[BadMouth]

You know the yellow wires go to the clutch and black is probably ground.
If one of the remaining wires is thicker than the others, it's probably power.
That leaves the remaining two as controls.

If you popped the little control box apart, it would be easier to tell.

[lilshawn]

no, the 2 pin connector is the clutch.

[BadMouth]

no, the 2 pin connector is the clutch.

The one going to the motor in the pics has red and blue wires and the connector is brown, which matches the 2 pin connector in the pinout.
The loom coming from the clutch looks like it has 2 yellow wires going into the main connector, although now that I look at it closer, I'm not sure the pins are going to the correct positions.

 

[TopJimmyCooks]

open the pod bay door, hal.

I can't do that, Dave.

[lilshawn]

oh, you may be right, i'mma have to look at this on my big screen when i get home, this piddly 15" i got at work, i can't see the whole thing.

[SithMaster]

open the pod bay door, hal.

I can't do that, Dave.

Needs a panic button.

[danny_galaga]

I would bet my left nut there are limit switches in it. Much like there are self parking switches in wiper motors. I would NOT hold any sway on colour of wires. Colour means nothing in the world of factory automotive wiring...

[Le Chuck]

Wiring woes aside this is a great re-purposing project, just make sure you have a wag bag and an MRE in the pod incase you have to wait for rescue.  You don't live alone do you?

We're gonna miss Kahlid   

[lilshawn]

Cragslist - Used Battletech Pod arcade videogame

comes with realistic skeleton sealed inside.

 $500 OBO

[kahlid74]

So the hatch door would be all wood, and since the inside of the POD is ~3 feet, I can ball up and then kick out pretty damn hard so if I ever got into a bind I would just kick the door down.  It's also too wide to move out of the door, so it would come standard with the purchase of the house including skeleton.

Okay, so joking aside here's where we get to the nitty gritty.  Two harness's:
MOTOR:
The motor has NO intelligence.  It has two wires, Blue and RED.  It's Drive Control Unit A:




So here's a wiring map so far:
Motor:
1). RED -> Green -> PTG-
2). Blue -> Red -> PTG+

Clutch:
1). Yellow -> Blue -> CLU+
2). -----
3). Yellow -> Grey -> CLU-
4). Pink -> Purple/White -> SVCC
5). Green -> Purple -> SENA
6). White -> Grey/Blue -> SENB
7). ----
8 ). Black -> Pink/Blue -> SEGA

So the power and polarity I have now, the question is what do SVCC/SENA/SENB/SEGA do.  They all hook into the Power Tailgate Control Unit so understanding this best is the key.

[TopJimmyCooks]

Okay, so joking aside here's where we get to the nitty gritty. 

Stop joking about getting stuck inside the pod, Hal.

I can't do that, Khalid74.

[HaRuMaN]

I'm gonna miss kahlid...

[BadMouth]

my GUESS:
SVCC = Sensor Voltage
SENA = Sensor A
SENB = Sensor B
SEGA = mount everything on a Afterburner Deluxe base for full motion (or maybe sensor ground) EDIT: or sensor gate, as in don't move it if latched.

This thread popped up when I searched for this stuff the other day.
http://www.odyclub.com/forums/27-diy-modifications/80947-add-oem-power-tailgate-rearview-camera-odyssey-07-project.html
It shows a left and right sensor. (It also shows a separate drive unit)


You have no need for such safety sensors!
Just start throwing some voltage to the motor and clutch already. 

[kahlid74]

(It also shows a separate drive unit)

Thanks for the idea of where to get started.  It's not actually a seperate drive motor, but instead the closing motor, for the latch inside the door.  I saw it when I was looking at the tech specification sheets for the Odyssey.

I got home today and removed the extended arm and wired up all the voltage from the tech specifications sheets (- to line/hot, + to com) and then used a computer power supply's 12v lead for the clutch and the motor.  I then used a power strip to turn it on and off:





So when I let the arm go until it hits it dies hard and won't turn back on again until I completely break the circuit and then re-establish it.  Even the PS won't turn back on until I unplug/re-plug it.

So here's my questions now:
1). How do I get it to go in reverse?  Change the polarity?
2). The sensors I imagine will stop it, so I just hook a wire up to one of the SENA and then to the ground and when it's close to the end I complete the circuit?  This maybe isn't as much of a question as it is something I'm going to try

[BadMouth]

So here's my questions now:
1). How do I get it to go in reverse?  Change the polarity?
2). The sensors I imagine will stop it, so I just hook a wire up to one of the SENA and then to the ground and when it's close to the end I complete the circuit?  This maybe isn't as much of a question as it is something I'm going to try

1) yup.

2) The sensors are only hooked up to the clutch.  Making the sensors engage or disengage may stop the movement, but it isn't going to stop the motor.
    I imagine the sensors are triggered when something is immediately in front of the hatch and about to be struck.  Then the clutch disengages and the door stops moving and a brain somewhere else tells the motor to reverse direction.  (all speculation  )  Anyone have an odyssey?

If this thing is going to be PC controlled, I'd go ahead and get a pololu simple motor controller and add your own limit switches to the mechanism itself.
Then you could adjust speed, braking, etc from your PC.  A pololu servo controller and a relay could be used to engage and disengage the clutch.
A script could then be written to make the canopy behave however you want.

If it's just goint to run off a switch, you can wire up a DPDT toggle switch to reverse the polarity and put a limit switch inline with the power for each direction.
The switches will have to be able to handle the current though.  This is how I wired up my rotating monitor temporarily while working out the bugs.
Been meaning to draw up a daigram for DaOldMan's circuits thread in the mrotate forum.

If the thing moves freely without the clutch engaged, the clutch can act as a safety mech.  When power is cut to the clutch, the canopy can be manually lifted.

[kahlid74]

So here's my questions now:
1). How do I get it to go in reverse?  Change the polarity?
2). The sensors I imagine will stop it, so I just hook a wire up to one of the SENA and then to the ground and when it's close to the end I complete the circuit?  This maybe isn't as much of a question as it is something I'm going to try

1) yup.

2) The sensors are only hooked up to the clutch.  Making the sensors engage or disengage may stop the movement, but it isn't going to stop the motor.
    I imagine the sensors are triggered when something is immediately in front of the hatch and about to be struck.  Then the clutch disengages and the door stops moving and a brain somewhere else tells the motor to reverse direction.  (all speculation  )  Anyone have an odyssey?

If this thing is going to be PC controlled, I'd go ahead and get a pololu simple motor controller and add your own limit switches to the mechanism itself.
Then you could adjust speed, braking, etc from your PC.  A pololu servo controller and a relay could be used to engage and disengage the clutch.
A script could then be written to make the canopy behave however you want.

If it's just goint to run off a switch, you can wire up a DPDT toggle switch to reverse the polarity and put a limit switch inline with the power for each direction.
The switches will have to be able to handle the current though.  This is how I wired up my rotating monitor temporarily while working out the bugs.
Been meaning to draw up a daigram for DaOldMan's circuits thread in the mrotate forum.

If the thing moves freely without the clutch engaged, the clutch can act as a safety mech.  When power is cut to the clutch, the canopy can be manually lifted.

Reverse the polarity of the clutch or the motor or both?  When the motor/clutch are off the rack and pinion still slide, so it can be worked manually for sure.

My thoughts were to control it with an Arduino hooked up to a keypad on the outside and a DPDT switch inside.  So when inside the cabinet you can manually raise/lower it but when outside you have to enter the code to get into the pod.  I've got all sorts of cool ideas for immersion with this pod making use of my 3D printers etc. so it would be fun to do these types of things.

[PL1]

If it's just goint to run off a switch, you can wire up a DPDT toggle switch to reverse the polarity and put a limit switch inline with the power for each direction.

Here's a diagram I drew up a while back for Tony.silveira in this post.



Feel free to use/modify however you see fit.


Scott

[BadMouth]

Reverse the polarity of the clutch or the motor or both?  When the motor/clutch are off the rack and pinion still slide, so it can be worked manually for sure.

Reverse polarity of the motor.  I'm assuming the clutch is like an air conditioner compressor clutch in a car, it's either engaged(powered) or disengaged (not powered).
It would not have a reverse.  It most likely just engages and disengages the motor's motion from the lift mechanism (via a powerful electromagnet).

If it did flip the gearing in the mechanism somehow to reverse direction, I'm not sure if it would still be called a clutch.

If you have the arduino know how, go for it!
I'm sure there are lots of resources out there concerning controlling motors.
I'd like to tinker with that stuff "someday".

[kahlid74]

Copy that Badmouth.

PL1, what are the limit switches for?

When I get home today I've got a spare DPDT switch I'll hook up and give it a go.

So now the big question, TORQUE.  On the Van, the motor, while using 20-40 AMPS doesn't really do the heavy lifting, the struts do.  So now the question would be do I need to incorporate struts into the hatch to make sure it goes up/down effortlessly.  The door will be wood, so it won't be too heavy, but it will still be heavy.

Then the next question comes down to the stress the hatch will be under when moving/stable in an upright position.  The hatch would be of an L design meaning the joint would have to be super re-enforced.  Some good wood glue and joints I assume would be fine but I wonder if I should use a piece of sheet metal bent 90 degrees for stabilization. 

[BadMouth]

If you happen to live anywhere near an airplane graveyard, you might be able to get an actual canopy cheaper than you think.
From what I understand, aircraft parts have to be retired after so many hours and are only worth their weight in scrap because they aren't allowed to be used again on a different aircraft.

[kahlid74]

If you happen to live anywhere near an airplane graveyard, you might be able to get an actual canopy cheaper than you think.
From what I understand, aircraft parts have to be retired after so many hours and are only worth their weight in scrap because they aren't allowed to be used again on a different aircraft.

It's a good idea but it won't work based on how the POD is deigned, being one of original concept to the VR 3.0 pods.

[PL1]

PL1, what are the limit switches for?

Video from Griffindodd's monitor rotation tests show limit switches being hit by the washer/bolt.



The limit switches are there because your motor/actuator has a longer travel distance than it takes to open/close the hatch or turn the monitor.

The switches are wired to the Normally Closed (NC) contact.  When not pressed, they are in the closed green position.  When pressed, they are in the open red position.

Your hatch starts in the fully up position with the upper limit switch pressed.

When you press down on the DPDT, the + voltage is applied through the lower limit switch to the "Down When +" and ground is applied to the "Up When +".

As you hold the switch down, the motor lowers the hatch until it presses the lower limit switch.

When the hatch presses the switch, the NC terminal is disconnected from the common (red position) which stops the motor from going lower even if you are still holding the switch down.

When you press up on the on the DPDT, the + voltage is applied through the upper limit switch to the "Up When +" and ground is applied to the "Down When +".

As you hold the switch up, the motor raises the hatch until it presses the upper limit switch.

When the hatch isn't all the way up or down, you can move it up or down at will since both limit switches are closed. (green position)



Long lever arm microswitches will give you a more precise adjustment of the stopping point.  Avoid nub microswitches, they lack the desired travel between actuation and bottoming out so you don't damage the switch.

If possible, rig two bolts so one head hits the upper limit switch and the other one hits the lower switch. 

Use a tee nut to hold the bolt and a second nut tightened against the tee nut to lock the bolt in place


Scott

[kahlid74]

I would have to find limit switches that support 20-40 amps at 12 volt.  Interesting idea.

[BadMouth]

I would have to find limit switches that support 20-40 amps at 12 volt.  Interesting idea.

I'm having trouble believing that thing draws that much current, especially if it had gas struts helping it.

[kahlid74]

I would have to find limit switches that support 20-40 amps at 12 volt.  Interesting idea.

I'm having trouble believing that thing draws that much current, especially if it had gas struts helping it.

I agrees completely but I was just going off the electrical troubleshooting guide from Honda.

[PL1]

I would have to find limit switches that support 20-40 amps at 12 volt.  Interesting idea.

Just looked for high amperage limit switches.      

You'll save a LOT of money changing this circuit to use relays to connect the high amperage up and down power to the motor.

Use a SPDT switch with up connected through the upper limit switch to the coil of the relay(s) connecting the high amperage power supply to the motor in the up direction.

The SPDT switch down is connected through the lower limit switch to the coil of the relay(s) connecting the high amperage power supply to the motor in the down direction.

The ground connections on the relay coils are always connected to ground.


Scott

[lilshawn]

you can use a regular microswitch and just have it go through a relay.

but also don't forget, your not trying to lift a 75lb door either... voltmeter is your best friend... hook it up and load down the motor and see what kind of amps it draws. i'll bet it's under 8 amps. ALRIGHT PEOPLE BETS ARE ON!

[kahlid74]

I used the Killawatt power meter last night and with no load, it's at 2 AMP.  I found a 20 amp 12volt DPDT Rocker switch and a bunch of 40amp 12volt relay's so I've got em all on order with arrival tomorrow.  This afternoon/evening I need to build the door and affix the motor to the top of the pod.  Building this door is going to be tricky because of the weird angles on the side.  The wife is out of town for 4 days and the little man is at his grandparents for the next two days so I've got lots of build time.  I'm going to hit up the junkyard today looking for struts.

[kahlid74]

So the top part of the hatch is now working as expected.


Rocker switch and relays have arrived.  Electrical wiring to commence.

I've cut the Side door but it needs a little trimming to fit.  The width was calculated wrong so I've got a 4x12 rectangle in the bottom left that is open.  If the current door fits/works I'll just affix another piece with an extension/wood glue/bondo

The motor arm is strong enough to lift the wood but when I hooked it up and tried it once I noticied that the arm moved away from the board in a slant, which since I affixed it to the wood with bolts got very tough about 50-85 degrees up.  The issue was the arm connects to the motor on a 45 degree slant, which is fine if it didn't move but when moves with the wood it moves out to the left, resulting in an angry motor.  To semi-resolve this I simply tilted the left side of the motor up, to where it's kind of slanted and the slant on the motor is more closely associated with a 70-80 degree above 0.

The motion up is a jerk at the start because it's easy but as it climbs it encounters resistance and becomes smooth.  The motion down is smooth until about 35-40 degrees above 0 and then it comes down hard.  I associate this to the fact that I can move the track on the motor moderately easy, which makes sense since you can also open the lift gate by hand.  So it's 100% confirmed that I will need struts to let the door close smoothly without force and also lift smoothly at the first phase.  I assume once I add the side door the motion up will be smooth with all the weight associated.

So now to find struts.  At the junkyard most are ballpoint, which creates a problem, since I really need the plate style.  Additionally it's anywhere in the range of 15 to -15 degrees out, and all of these struts are firmly in their associated cars.  The motor was easily removed with two bolts but these struts I'll have to take apart lots of paneling and I just don't want to be out there spending so much time doing that.  I might take a trip back and check it out again.

[BadMouth]

Cool.  I want one to mess around with!
I was thinking it would be inside the pod, like on the van.
Nice move putting it on top.

The motion up is a jerk at the start because it's easy but as it climbs it encounters resistance and becomes smooth.  The motion down is smooth until about 35-40 degrees above 0 and then it comes down hard.  I associate this to the fact that I can move the track on the motor moderately easy, which makes sense since you can also open the lift gate by hand.  So it's 100% confirmed that I will need struts to let the door close smoothly without force and also lift smoothly at the first phase.  I assume once I add the side door the motion up will be smooth with all the weight associated.

The Pololu software allows you to start the motor out slow and brake as it nears the limit switches.
I imagine people have accounted for this with the Arduino as well.

As long as the motor isn't overloaded by the door, you could most likely smooth out the motion in software.

They also make adjustable gas struts, but I've never used them.

[kahlid74]

Cool.  I want one to mess around with!
I was thinking it would be inside the pod, like on the van.
Nice move putting it on top.

The motion up is a jerk at the start because it's easy but as it climbs it encounters resistance and becomes smooth.  The motion down is smooth until about 35-40 degrees above 0 and then it comes down hard.  I associate this to the fact that I can move the track on the motor moderately easy, which makes sense since you can also open the lift gate by hand.  So it's 100% confirmed that I will need struts to let the door close smoothly without force and also lift smoothly at the first phase.  I assume once I add the side door the motion up will be smooth with all the weight associated.

The Pololu software allows you to start the motor out slow and brake as it nears the limit switches.
I imagine people have accounted for this with the Arduino as well.

As long as the motor isn't overloaded by the door, you could most likely smooth out the motion in software.

They also make adjustable gas struts, but I've never used them.

The initial idea was inside but once I actually looked at it, the part that went up with a curve wasn't practical at all.  So I removed it, then I wound up grinding a bunch of the arm down and I then settles on the arm and bottom attachment.

[danny_galaga]

So the top part of the hatch is now working as expected.


Rocker switch and relays have arrived.  Electrical wiring to commence.

I've cut the Side door but it needs a little trimming to fit.  The width was calculated wrong so I've got a 4x12 rectangle in the bottom left that is open.  If the current door fits/works I'll just affix another piece with an extension/wood glue/bondo

The motor arm is strong enough to lift the wood but when I hooked it up and tried it once I noticied that the arm moved away from the board in a slant, which since I affixed it to the wood with bolts got very tough about 50-85 degrees up.  The issue was the arm connects to the motor on a 45 degree slant, which is fine if it didn't move but when moves with the wood it moves out to the left, resulting in an angry motor.  To semi-resolve this I simply tilted the left side of the motor up, to where it's kind of slanted and the slant on the motor is more closely associated with a 70-80 degree above 0.

The motion up is a jerk at the start because it's easy but as it climbs it encounters resistance and becomes smooth.  The motion down is smooth until about 35-40 degrees above 0 and then it comes down hard.  I associate this to the fact that I can move the track on the motor moderately easy, which makes sense since you can also open the lift gate by hand.  So it's 100% confirmed that I will need struts to let the door close smoothly without force and also lift smoothly at the first phase.  I assume once I add the side door the motion up will be smooth with all the weight associated.

So now to find struts.  At the junkyard most are ballpoint, which creates a problem, since I really need the plate style.  Additionally it's anywhere in the range of 15 to -15 degrees out, and all of these struts are firmly in their associated cars.  The motor was easily removed with two bolts but these struts I'll have to take apart lots of paneling and I just don't want to be out there spending so much time doing that.  I might take a trip back and check it out again.

Damn, that is looking good!  Bear in mind no load is VERY different to loaded with car stuff. The figures you saw before sound about right. A stalled DC motor is essentially a short. If it's connected to a 12V battery, I reckon 50 amps easy. Of course, if it's connected to a power supply, it probably can't even supply 50 amps (the battery can supply nearer 1000). I'd say in operation with some load it would be between 10 and 20 amps (with a battery). Anyway, it all seems moot now since you have it working!

[danny_galaga]

Oh, and with the clutch. Just had a thought. If it needs to be powered on to engage, you could hook it up to an automotive pop out circuit breaker, say 15 or 20 amps. If the hatch overloads because you got your neck stuck in there (we'll miss you Kahlid!) then it'll pop and hatch is free. Of course you'd definitely want struts because if it popped near fully open, then the lid might slam down hard.

You've inspired me for a a future project I've been thinking about. This is great work!

About the struts. I used to work at an architectural hardware wholesaler. they also sold gas struts, which they had the machinery to gas to various pressures. This isn't going to help you directly, because I live in Australia, but it's food for thought for another line of inquiry. I can't remember what the cost of the struts was though...

Man, you've got me thinking though!

[kahlid74]

UGH.  So I got the side door attached and I recessed it into the pod and then fuuuudggge, I realized that the mechanism is going to pull the door up a little bit before it pulls it out.  I haven't run the motor yet with it but I fear it won't go up cause it will be stuck.  Son of a bees wax.  There's me and my not actually thinking it through before I go wood glue/nailing/screwing it together.  Fudge sticks.

[PL1]

Looks like your main problem will be with the area outlined in red.

Most of that length will probably just need an almost full-depth 45 degree chamfer like the diagram on the right.

If that doesn't quite clear the upper fixed edge, you can cut the edge back and use countersunk aluminum flat stock on the door to bridge the gap.



Scott

[kahlid74]

Looks like your main problem will be with the area outlined in red.

Most of that length will probably just need an almost full-depth 45 degree chamfer like the diagram on the right.

If that doesn't quite clear the upper fixed edge, you can cut the edge back and use countersunk aluminum flat stock on the door to bridge the gap.



Scott

Good call.  I'll look at the tools I have and how I could make this cut.  Jigsaw/Circular Saw/Router.  Hmmm.  I'm not really going to be able to take the door off so it's going to be a tricky cut.

[BadMouth]

I realized that the mechanism is going to pull the door up a little bit before it pulls it out.

I thought that when you posted drawings, but didn't comment because I thought it would be stating the obvious. 
I just assumed the door was going to be oversized and on the outside of the pod in real life.

[BadMouth]

You could ditch the whole door lifting idea and have it slide toward the front.
I think it would look cool.  It would be easier to do and require no clearance.

[TopJimmyCooks]

Did you pull the ac unit from that Honda?  looks like it's gonna be hot in there. 

[PL1]

I'll look at the tools I have and how I could make this cut.  Jigsaw/Circular Saw/Router.  Hmmm.  I'm not really going to be able to take the door off so it's going to be a tricky cut.

Maybe a piece of lumber (1x4, 2x4, etc.) screwed to the door to act as a straight edge guide for your router?

Drill start and stop holes for the router bit.

Chain drill several small holes and use a chisel to carefully break through the last little bit.


Scott

[danny_galaga]

Did you pull the ac unit from that Honda?  looks like it's gonna be hot in there.

[kahlid74]

Did you pull the ac unit from that Honda?  looks like it's gonna be hot in there.

There's two fans in the back that will be hooked up to a temp control system and will vary their fans accordingly.  If it gets hotter than that I'll brainstorm more fun ways to cool it down.

I'll look at the tools I have and how I could make this cut.  Jigsaw/Circular Saw/Router.  Hmmm.  I'm not really going to be able to take the door off so it's going to be a tricky cut.

Maybe a piece of lumber (1x4, 2x4, etc.) screwed to the door to act as a straight edge guide for your router?

Drill start and stop holes for the router bit.

Chain drill several small holes and use a chisel to carefully break through the last little bit.
Scott

I think what I'm going to do is take the door all the way off.  It's only on by the hinges and motor arm.  so I can take it off completely and then reaffix it.

[bkenobi]

I imagine that motor is pretty strong if it's designed to lift a tailgate (even with gas shocks).  What provisions have you made to keep the door from removing fingers and/or heads?

[kahlid74]

I imagine that motor is pretty strong if it's designed to lift a tailgate (even with gas shocks).  What provisions have you made to keep the door from removing fingers and/or heads?

Great question and requires a multifaceted answer:
The first set of sensors will be connected to Relays specific to the door's position at the end of opening or closing.  I plan to use micro-switches to identify when it's closed/opened and to kill power to the clutch/motor.  This way the doors motion will stop when it hits either of those positions.

The second set of sensors would be pressure sensitive and will be quite a bit more difficult to achieve.  Since the clutch has built in sensor controls, on a car when the liftgate encounters resistance it triggers one of these sensors (resistance closing/opening) and disengages the clutch.  I want to achieve something similar to this as a phase 2.  The challenging part will be hooking up the sensors to measure resistance and understanding how to get the clutch to disengage once resistance has been acknowledged (simply connected the pins didn't do it, so I wonder if I have to send a charge through)

[HaRuMaN]

I'm gonna miss kahlid74...

[bkenobi]

If you were to have the door slide, using a pressure switch of some kind would work great.  But, this arrangement is rotating.  If you set the pressure switch to an appropriate value such that a limb won't be severed near the bottom of the door, there's likely enough force on top of the cab next to the hinge to remove a finger real clean like!  I love the concept, but I'm wondering if you might be better off with either:

• A sliding door as suggested earlier
• Making the gap between the doors larger such that a finger or small person's arm would not be injured by a closure (~2" seems safe to me).  You can use some type of rubber molding to mate the 2 surfaces such that they still seal tightly.

This is a hobby that should be fun.  Rushing to the ER with a finger in ziplock doesn't sound fun IMO.

[kahlid74]

If you were to have the door slide, using a pressure switch of some kind would work great.  But, this arrangement is rotating.  If you set the pressure switch to an appropriate value such that a limb won't be severed near the bottom of the door, there's likely enough force on top of the cab next to the hinge to remove a finger real clean like!  I love the concept, but I'm wondering if you might be better off with either:

• A sliding door as suggested earlier
• Making the gap between the doors larger such that a finger or small person's arm would not be injured by a closure (~2" seems safe to me).  You can use some type of rubber molding to mate the 2 surfaces such that they still seal tightly.

This is a hobby that should be fun.  Rushing to the ER with a finger in ziplock doesn't sound fun IMO.

Thanks for the feedback!

I feel like if I used the sliding door the same issue would be present.  To prevent a swing of the door I would solidly hook it to the chassis and then it would have the same ability to lop a finger off. 

Making the gap larger kind of gets away from what I was going for with it blocking out all light from the outside world but in the end, we'll see what I can work out.

[bkenobi]

No matter how you make the door move, if it is controlled by a motor there will always be a risk of injury unless the motor is not strong enough to cause said injury.  Of course, you can have just as serious a problem with a motor that fails and allows the door to drop.  I'm not in the automobile industry, but I'm confident that there has been a lot of work done on this topic in regards to tailgates.

I saw an episode of Top Gear where they showed a Cadillac with a mechanism that would automatically latch when the trunk lid got within an inch or so of closed.  This seems like a cool feature, but they termed it the "finger amputator" (or something like that).

[kahlid74]

No matter how you make the door move, if it is controlled by a motor there will always be a risk of injury unless the motor is not strong enough to cause said injury.  Of course, you can have just as serious a problem with a motor that fails and allows the door to drop.  I'm not in the automobile industry, but I'm confident that there has been a lot of work done on this topic in regards to tailgates.

I saw an episode of Top Gear where they showed a Cadillac with a mechanism that would automatically latch when the trunk lid got within an inch or so of closed.  This seems like a cool feature, but they termed it the "finger amputator" (or something like that).

If you ever get a chance or want to dig into it, the electrical guides for the Hatch Lift gate powered mechanism are a fantastic read.  Currently, all doors have two motors, one for the lift/close action and one for the latch.  So the latch you talk about is found in every trunk that automatically closes, which are millions of cars.  I'm not saying it's not dangerous, but it's been proven to be minimal.  Minimal still doesn't remove the fact that it can occur though.

So with either resistance sensors or plane threshold sensors the clutch would break the motion of the motor in milliseconds which, if you watch it slow motion would not remove a finger but crimp/bruise it.

At the end of the day I really appreciate your feedback and it makes me re-think the design.  I still want to do this to fruition and see how it works.  Once completed I'll see how bad it really is and then work with it or re-work it.

Just a side note, machines that are super dangerous can still be prevented from causing any harm.  Just look at the sawstop.

[jammin0]

Build away man.  I think this is pretty sweet.  Instead of worrying too much about safety, simply worry about disassociating yourself with anyone who is so accident prone as to stick their finger in a closing door.  WWDS What would Darwin say.

Seriously though, make sure you get a video up as soon as that sucker is working.  Super cool idea.  I'm glad that the nearest salvage yard is 45 minutes away from me.

[bkenobi]

I agree!  Build it and let nature take it's course.  From what I'm imagining in my head, this thing should look awesome when complete.   

[lilshawn]

So with either resistance sensors or plane threshold sensors the clutch would break the motion of the motor in milliseconds which, if you watch it slow motion would not remove a finger but crimp/bruise it.

i would imagine a system properly installed in a car would monitor the amperage being drawn from the motor whilst opening or closing, if it exceeds a pre-determined threshold, the motor stops and reverses direction.

perhaps a similar setup could be employed with this motor with an amp shunt and an AVR or PIC programmed to monitor both the forward and reverse direction and choose a threshold appropriately. the ampere shunt will "output" a millivolt diference dependent on the load applied to the circuit.

example: the motor whilst opening will encounter a great increase in amp load if something gets in the way and stops it. **normally 5 amps but will spike to 11amps if obstructed**

the motor whilst closing will experience a significant drop in amp load then great increase in load. (ie pinched finger) **normally 1 amps (due to weight of door) but drops to 0.3 amps then spikes to 11 amps** this system could stop and reverse once >2 amps is seen or once the spike is seen.

[kahlid74]

Looks like your main problem will be with the area outlined in red.

Most of that length will probably just need an almost full-depth 45 degree chamfer like the diagram on the right.

If that doesn't quite clear the upper fixed edge, you can cut the edge back and use countersunk aluminum flat stock on the door to bridge the gap.



Scott

So I did this and it didn't work well enough.  So I'm probably going to have to move things a little bit and see if I can get it to function.  I didn't get much time tonight to futz with it but come Thursday I'll have lots of time.

So with either resistance sensors or plane threshold sensors the clutch would break the motion of the motor in milliseconds which, if you watch it slow motion would not remove a finger but crimp/bruise it.

i would imagine a system properly installed in a car would monitor the amperage being drawn from the motor whilst opening or closing, if it exceeds a pre-determined threshold, the motor stops and reverses direction.

perhaps a similar setup could be employed with this motor with an amp shunt and an AVR or PIC programmed to monitor both the forward and reverse direction and choose a threshold appropriately. the ampere shunt will "output" a millivolt diference dependent on the load applied to the circuit.

example: the motor whilst opening will encounter a great increase in amp load if something gets in the way and stops it. **normally 5 amps but will spike to 11amps if obstructed**

the motor whilst closing will experience a significant drop in amp load then great increase in load. (ie pinched finger) **normally 1 amps (due to weight of door) but drops to 0.3 amps then spikes to 11 amps** this system could stop and reverse once >2 amps is seen or once the spike is seen.

Interesting thoughts.  Challange is that the Clutch is on a different system than the motor.  So the clutch diengages and then the power needs to be cut from the motor, then reversed and then re-engaged.  I like what your saying thought.  Should be feasible through the arduino.

[danny_galaga]

So with either resistance sensors or plane threshold sensors the clutch would break the motion of the motor in milliseconds which, if you watch it slow motion would not remove a finger but crimp/bruise it.

i would imagine a system properly installed in a car would monitor the amperage being drawn from the motor whilst opening or closing, if it exceeds a pre-determined threshold, the motor stops and reverses direction.

perhaps a similar setup could be employed with this motor with an amp shunt and an AVR or PIC programmed to monitor both the forward and reverse direction and choose a threshold appropriately. the ampere shunt will "output" a millivolt diference dependent on the load applied to the circuit.

example: the motor whilst opening will encounter a great increase in amp load if something gets in the way and stops it. **normally 5 amps but will spike to 11amps if obstructed**

the motor whilst closing will experience a significant drop in amp load then great increase in load. (ie pinched finger) **normally 1 amps (due to weight of door) but drops to 0.3 amps then spikes to 11 amps** this system could stop and reverse once >2 amps is seen or once the spike is seen.

Oh, and with the clutch. Just had a thought. If it needs to be powered on to engage, you could hook it up to an automotive pop out circuit breaker, say 15 or 20 amps. If the hatch overloads because you got your neck stuck in there (we'll miss you Kahlid!) then it'll pop and hatch is free. Of course you'd definitely want struts because if it popped near fully open, then the lid might slam down hard.

SAAL  (simplify, and add lightness  )

[kahlid74]

The biggest thing right now is getting the door to open/close with the side part.  I'm still not 100% with what to do on this sucker.  I thought a bunch last night and had resolved to take about 1/4 to 1/3" off the problem angle but I still wonder if that would even work.  It might make more sense to just remove the side door and then redo it only phased slightly out so it can pop out.  Ugh.  I had a lot of time to think last night with the little guy up most of the night with a nasty cold.

As a side note, I've started programming the Arduino.  I'm going to actually use the rocker switch with the Arduino as a first test, so that the Arduino uses both relays (one for on/Off and one for polarity).  Once I build that into a function I'll be able to copy/paste it into the Keypad section and we should be all set.  Something I'd really like to do is have a weight sensor on the seat so when the door closes and > 75lbs is on the seat initiate ---smurfette--- Betty "Reactor Online, Sensors Online, Weapons Online, All systems nominal" through the speakers.  Only problem is I'm not sure if Arduino can do this.  So I may wind up using a Raspberry Pi with the GPIO for this.  Just something I was thinking of that would really add ambiance.

[BadMouth]

I'd make the door slightly oversized and rest on the outside of the main body.

An easy way to appease the safety police would be to join the main part of the door to the part that's being lifted by hinges on top.  Maybe sprung hinges.
The door should still stay rigid as it is being lifted, but if something gets interferes on the way when it's closing, the motor will keep moving to the closed position, but the springs on the door will keep it from crushing fingers (anymore than the weight of the door could crush fingers).

[kahlid74]

I'd make the door slightly oversized and rest on the outside of the main body.

An easy way to appease the safety police would be to join the main part of the door to the part that's being lifted by hinges on top.  Maybe sprung hinges.
The door should still stay rigid as it is being lifted, but if something gets interferes on the way when it's closing, the motor will keep moving to the closed position, but the springs on the door will keep it from crushing fingers (anymore than the weight of the door could crush fingers).

Ugh, but it's so freaking big dude.  I also would need a door slightly large than 4' tall which the limit my car can transfer at any give time.  I suppose I could try this and see how it works.  I suppose I should try it.  I'll do it Thursday when I get a good chunk of free time in the afternoon.

[Gray_Area]

I'm lost. I was lost at the outset. What the hell is this?

[kahlid74]

I'm lost. I was lost at the outset. What the hell is this?

I'll be starting a build thread soon but essentially I'm making a Battletech VR 3.0 POD with a hatch door that opens automatically via a Power Liftgate Motor.

[BadMouth]

I'd make the door slightly oversized and rest on the outside of the main body.

An easy way to appease the safety police would be to join the main part of the door to the part that's being lifted by hinges on top.  Maybe sprung hinges.
The door should still stay rigid as it is being lifted, but if something gets interferes on the way when it's closing, the motor will keep moving to the closed position, but the springs on the door will keep it from crushing fingers (anymore than the weight of the door could crush fingers).

Ugh, but it's so freaking big dude.  I also would need a door slightly large than 4' tall which the limit my car can transfer at any give time.  I suppose I could try this and see how it works.  I suppose I should try it.  I'll do it Thursday when I get a good chunk of free time in the afternoon.

Does the door have to extend to the bottom edge of the cab?  I think it would look just as good with a 5 or 6 inch sill that you have to step over to get in (think Jeep Wrangler)

[kahlid74]

I'd make the door slightly oversized and rest on the outside of the main body.

An easy way to appease the safety police would be to join the main part of the door to the part that's being lifted by hinges on top.  Maybe sprung hinges.
The door should still stay rigid as it is being lifted, but if something gets interferes on the way when it's closing, the motor will keep moving to the closed position, but the springs on the door will keep it from crushing fingers (anymore than the weight of the door could crush fingers).

Ugh, but it's so freaking big dude.  I also would need a door slightly large than 4' tall which the limit my car can transfer at any give time.  I suppose I could try this and see how it works.  I suppose I should try it.  I'll do it Thursday when I get a good chunk of free time in the afternoon.

Does the door have to extend to the bottom edge of the cab?  I think it would look just as good with a 5 or 6 inch sill that you have to step over to get in (think Jeep Wrangler)

Great question.  At some point I may in fact cut it in half, because of it's weight and stability but right now it's kind of a challange, to make it work as is.

So I reattached the door, outside and it can now move up/down with a little effort.  I also installed some screen door springs to give it some more stability from the top.  I've got the struts on order from the auto dealership and they should arrive tomorrow.  I'll try to install them over the weekend.  The junkyard wanted 10 a pop for old used ones, the dealership wanted 15 a pop but I got them down to 12 for new ones.  The dealership also ordered me 20 so I can try a bunch of different sizes and PSI and then just keep what works.  So I'm excited now to get it in.

I've begun programming the arduino.  Phase 1 is making the arduino be the brains for two relays and two arcade buttons.  When you press one button it goes one way and when you press the other it goes the opposite.  These functions in the Arduino will be re-used with the keypad.

[kahlid74]

I'm back to working on this after throwing rocks on ice and something isn't adding up mechanically.  The rear door of a minivan is in two states, up or down.  this is done by the gas struts.  Even without actually closing the door it stays down.  When pulled the gas struts push the rest of the way with no outside effort.  This behavior is NOT exhibited within the pod hatch door and I've got no clue.

So I built the whole door, and with two 40Lbs struts, part 819-5564 (Napa strut) from the dealer, the door is not held up and will slam hard down.  Even with two screen door springs on the top.  I then removed one of the 40Lbs struts with a monster strut I also got, which I'm betting was one actually used in the tailgate lift.  The problem then was the wood would bend upward and it wouldn't close/stay closed.  Even with this monster it still didn't hold it open at the top either.




So then I cut the door in half and tried the 40lbs Struts again.  Still not enough =p



I hold it up and then when I let go it comes down.  Not as hard as the full door but hard enough.  The two pieces of wood are on the sides to prevent it from slamming down.

So I'm at a loss here.  What am I not doing right with regard to Gas Struts?  Have I just not found the right lbs force ones yet or is there something amiss?

Any help/suggestions would be a huge help!

[TopJimmyCooks]

Suggest place emergency collect call to mechanical engineers in Toyota City, Japan. 

but seriously, those two stage struts are tuned to the job, door weight and geometry and custom spec'd to the nth degree.  Have you considered a sliding door?  I do know that the strut will be almost parallel with the top part of the door when closed- that's how it is in the car.  Yours is at a steep angle when closed and flat/parallel when fully open - the opposite of how it works on the minivan. 

[kahlid74]

Suggest place emergency collect call to mechanical engineers in Toyota City, Japan. 

but seriously, those two stage struts are tuned to the job, door weight and geometry and custom spec'd to the nth degree.  Have you considered a sliding door?  I do know that the strut will be almost parallel with the top part of the door when closed- that's how it is in the car.  Yours is at a steep angle when closed and flat/parallel when fully open - the opposite of how it works on the minivan.

So the angle would be different, but it would still be completely collapsed.

I have thought about a sliding door, since it is what the original Pods had and while I'm generally okay with it, I was kind of hoping to do something different/special.  Either way it's moot now with the current state it's in.

[HaRuMaN]

Your problem here is torque.  Try pushing open a heavy door near the hinges vs. near the outer edge to see what I mean.

[BadMouth]

Your problem here is torque.  Try pushing open a heavy door near the hinges vs. near the outer edge to see what I mean.

+1
beat me to it

You're working with leverage here.

[kahlid74]

Your problem here is torque.  Try pushing open a heavy door near the hinges vs. near the outer edge to see what I mean.

That makes sense.  Looking at some pictures of liftgates in cars they are a bit away from the hinges.  If it was a straight box I would be able to move the hingers to the front but because of the weird angles in the front I can't do that.

I took off the side door completely and with one 30Lbs force strut it works exactly as expected.  No slamming, no fast open, just fluid opening like a tailgate.  I'm rolling some electrical right now for a test run and then I'll post a video.

Now I just need to figure out what I'm going to do with the side door.

[kahlid74]

SO now I have electrical issues.  While I'm still rocking and rollign on using Arduino to control the up down I wanted to use a DPDT switch to just see how it would work.  Long story short, I can't get it to work.  it still works if I wire the motor regular or reverse polarity to the power supply but when I go through the DPDT switch it's like it gets grounded and the PS turns off and won't come back until I unplug, let sit for 20 secs and then replug.  Side note, the Clutch is plugged directly into the power supply since I don't think you're suppose to reverse polarity on the clutch right?

This is how I have the DPDT wired:


Any ideas?

[PL1]

Looks like the wiring is correct for reversing polarity.

I'm assuming that the switch is:

1. Non-illuminated
2. Momentary-Off-Momentary DPDT switch
3. Rated for the required amperage and voltage
4. The power supply +/- is connected to 1/2 and the motor is connected to 1a/2a or vice-versa.

The only other thing I can think of is to ohms check the switch separate from the wiring.

1a 2a
 1   2
1b 2b

Switch Centered
Connect one lead to 1, connect other lead to 1a, 1b, 2, 2a, and 2b.  All should read open.

Connect one lead to 2, connect other lead to 1, 1a, 1b, 2a, and 2b.  All should read open.

Switch Up
Connect one lead to 1, connect other lead to 1a.  It should read continuity.
Connect one lead to 1, connect other lead to 1b, 2, 2a, and 2b.  All should read open.

Connect one lead to 2, connect other lead to 2a.  It should read continuity.
Connect one lead to 2, connect other lead to 1, 1a, 1b, and 2b.  All should read open.

Switch Down
Connect one lead to 1, connect other lead to 1b.  It should read continuity.
Connect one lead to 1, connect other lead to 1a, 2, 2a, and 2b.  All should read open.

Connect one lead to 2, connect other lead to 2b.  It should read continuity.
Connect one lead to 2, connect other lead to 1, 1a, 1b, and 2a.  All should read open.


Scott

[BadMouth]

The switch looks wired correctly to me.
Is it rated for the amount of current you're drawing?

You wouldn't reverse polarity on the clutch, but I'd see if the switch works without the clutch hooked up as part of the troubleshooting.

Might be time to break out the relays and get a little more complicated.

[kahlid74]

Thanks for the replies guys.  The DPDT is rated for 12V at 20 AMPS so I know we're good to go on that front.  The clutch is DISCONNECTED which is where I'm guessing this is breaking down.  When I power on the PS I hear the clutch activate but the motor obviously doesn't turn on.  I'm thinking of trying the motor with the clutch connected to the UP switch and seeing if it works.  If it does, how do I wire the clutch into the DPDT while preventing it from ever reversing polarity?

[PL1]

How about using a bridge rectifier to drive a relay.

Connect the bridge rectifier inputs in parallel with the motor voltage and the outputs to the coil of the relay.



The circuit is usually used to convert AC to DC, but will work for this purpose as long as you use the right diodes.

Regardless of the polarity, when a voltage is applied to the motor, it applies power to the relay coil, closing the contacts which applies the 12v operating voltage to the clutch.


Scott

[kahlid74]

How about using a bridge rectifier to drive a relay.

Connect the bridge rectifier inputs in parallel with the motor voltage and the outputs to the coil of the relay.



The circuit is usually used to convert AC to DC, but will work for this purpose as long as you use the right diodes.

Regardless of the polarity, when a voltage is applied to the motor, it applies power to the relay coil, closing the contacts which applies the 12v operating voltage to the clutch.


Scott

Awesome idea!  I did however figure out what the issue was.

The clutch is not the culprit and if not energized, the arm doesn't move even though the motor does.  So here's what I found out, my PS, an Antec 600 Watt was too smart.  Something in the power supply didn't like the DPDT configuration.  I then grabbed a cheapo PS 300 watt no name from the corner of shame, wired it up without the clutch and it works like a SOB.  Sweetness.

So what do you think my Antec PS was seeing that caused it to kill the PS when power was sent through the DPDT.  I also used my Killowat meter and only 1.4 amps were running through the system at the time of the motor running.  So it can't be an amp thing can it?

[PL1]

Maybe the Antec PS interpreted the sudden jump in current as a short and shut down to "protect" the system.   


Scott

[kahlid74]

Perhaps it's the motor?  I hooked up a 10A 12VDC DPDT Relay.  The trigger switch works and I can see it work.  Everything is happy except when I try to draw power through it via the motor.  Without the motor I get 12V in either regular or reverse polarity.  So now I'm not sure what's going on.  Is my relay really unable to power the motor?  It's the weirdest thing.  Doesn't make any sense.

[PL1]

Perhaps it's the motor?  I hooked up a 10A 12VDC DPDT Relay.  The trigger switch works and I can see it work.  Everything is happy except when I try to draw power through it via the motor.  Without the motor I get 12V in either regular or reverse polarity.  So now I'm not sure what's going on.  Is my relay really unable to power the motor?  It's the weirdest thing.  Doesn't make any sense.

IIRC you mentioned previously that you had measured the no-load current draw at about 2A -- I assume that means that the motor works when connected directly.   

When in doubt, draw it out.

A diagram showing how you've got everything hooked up might help clarify things.   


Scott

[kahlid74]

So it's basically the motor.  It's shorting for some reason.  I proceeded to hook it up to an ac adapter which provides 12v 7 Amps and basically it's tripping out.  It sounds like it's clicking or something else weird.  I'll try to take a video and see if I can isolate it but I'm at a loss.  Did the motor burn out or die?  Did I brick it somehow?  Is there a way to un-brick it?  What could I have done to mess it up?

[danny_galaga]

Thanks for the replies guys.  The DPDT is rated for 12V at 20 AMPS so I know we're good to go on that front.  The clutch is DISCONNECTED which is where I'm guessing this is breaking down.  When I power on the PS I hear the clutch activate but the motor obviously doesn't turn on.  I'm thinking of trying the motor with the clutch connected to the UP switch and seeing if it works.  If it does, how do I wire the clutch into the DPDT while preventing it from ever reversing polarity?

I know you've advances somewhat in the troouble-shooting, but bear in mind there is no 'polarity' for a clutch coil- it will work the same no matter which way it's wired (",)

[kahlid74]

Thanks for the replies guys.  The DPDT is rated for 12V at 20 AMPS so I know we're good to go on that front.  The clutch is DISCONNECTED which is where I'm guessing this is breaking down.  When I power on the PS I hear the clutch activate but the motor obviously doesn't turn on.  I'm thinking of trying the motor with the clutch connected to the UP switch and seeing if it works.  If it does, how do I wire the clutch into the DPDT while preventing it from ever reversing polarity?

I know you've advances somewhat in the troouble-shooting, but bear in mind there is no 'polarity' for a clutch coil- it will work the same no matter which way it's wired (",)

Good to know, thanks!

So does anyone have any ideas on the motor?  Did I destroy it somehow?

[BadMouth]

So does anyone have any ideas on the motor?  Did I destroy it somehow?

Did it smoke?
Does it turn freely by hand?

Maybe that sucker does draw more than 10A and is overwhelming the relay.

[kahlid74]

So does anyone have any ideas on the motor?  Did I destroy it somehow?

Did it smoke?
Does it turn freely by hand?

Maybe that sucker does draw more than 10A and is overwhelming the relay.

No smoke, I can move the slider back and forth freely, which is what the motor is connected to, so it should be good there.

That's what I was thinking too, more than 10AMP wise but wouldn't my Kilowat plug see that?  When someone spikes it shows on the kilowat..  Could it be similar to the draw of an HDD that has a high peak start-up and then settles down?  The issue now is I can't even get the motor working plugged directly into a power supply.  I'm at a loss.

[lilshawn]

the problem with a kilowat plug is that you are only seeing the input side of the power supply. you aren't seeing any of the work being done.

take my ridiculous welding transformer for instance, going in is only ~1000 watts (~10 amps) but it outputs ~1300 amps.(~3000 watts) where did all this extra crap come from? ohms law that's where.

you need to actively measure the motor draw. Your motor is drawing more than the power supply is designed to output. I'm not even going to get into rail load requirements for proper voltage regulation.

yah, yah, yah i know it says 30 whatever amps on this rail and that rail but seriously, that ish is made up. hit up some power supply test reviews. hardly a single power supply now a days can hit the rated wattage listed on the label without blowing up or catching fire.

go get yourself a car battery (or take it out to your car) and hook 'er up. you will know in 2 seconds if your motor works or not.

[kahlid74]

the problem with a kilowat plug is that you are only seeing the input side of the power supply. you aren't seeing any of the work being done.

take my ridiculous welding transformer for instance, going in is only ~1000 watts (~10 amps) but it outputs ~1300 amps.(~3000 watts) where did all this extra crap come from? ohms law that's where.

you need to actively measure the motor draw. Your motor is drawing more than the power supply is designed to output. I'm not even going to get into rail load requirements for proper voltage regulation.

yah, yah, yah i know it says 30 whatever amps on this rail and that rail but seriously, that ish is made up. hit up some power supply test reviews. hardly a single power supply now a days can hit the rated wattage listed on the label without blowing up or catching fire.

go get yourself a car battery (or take it out to your car) and hook 'er up. you will know in 2 seconds if your motor works or not.

Thanks for more info man.  I'm not super familiar with this stuff, only the basics, so any place to start troubleshooting is good to go.  So from a high level, why would it work before with the PS and now not work?  Perhaps the PS is no longer able to supply the power it needs?

[DaOld Man]

Maybe Im missing something here, but does the clutch maybe have a diode across the coil for snubber control? If so, if you reverse the current on the clutch you could be shorting out the power supply.
(This may have already been discussed, I havent intensely read every post.)
If this cant be the problem, if you can remove the brushes on the motor, take them out and see if one is broken.
Do you have a 10 amp auto battery charger? You can try the motor on it.

[kahlid74]

Maybe Im missing something here, but does the clutch maybe have a diode across the coil for snubber control? If so, if you reverse the current on the clutch you could be shorting out the power supply.
(This may have already been discussed, I havent intensely read every post.)
If this cant be the problem, if you can remove the brushes on the motor, take them out and see if one is broken.
Do you have a 10 amp auto battery charger? You can try the motor on it.

I have a battery charger yeap.  I'll go grab it and try that.

[kahlid74]

Lilshawn you are right.  The draw of AMPs is above 10 so the relay is failing, but are relays supposed to give an indication of when they fail?

Thanks DaOld Man, I hooked up my Lanmower charger which is supposed to be 6AMP at 12volt and the amp gauge went way off the side over 8 AMPs and the motor ran.

So I need a stronger relay and I need a solid PS that's 12volt 20AMP.

Thanks again guys!

[DaOld Man]

Yeah I kinda figured that.
The power supply needs to be beefy, but it doesnt have to be regulated for a motor. A 10 amp transformer with a 20 amp bridge rectifier and maybe one beefy capacitor for a filter should be just fine.
The regulated power supplies are probably not good for motors, since they do have a short circuit protection and may see the motors start up current as a short.
Its not like the motor is going to be running constantly, so I wouldnt go overboard, since a bigger transformer means more floor space needed. (A 10 amp battery charger may be all you need.)

[lilshawn]

A Relay will usually end up with stuck contacts if the amperage is too high.

I suspect the power supply output regulator has had enough and is shutting off on you (overload protection)

i wouldn't use that power supply for a computer anymore.

[danny_galaga]

To be REALLY sure what the motor does, you should get a car battery like Lilshawn says, and hook up an ammeter (or an induction loop thingo on a digital voltmeter) so you can see what the true current draw is- loaded and unloaded. Just remember that a DC motor draws STACKS of power at start up (because it has an effectively very low resistance) and at speed draws a lot less. For instance your typical car starter might draw 50 amps or so just free spinning, and say 200 amps cranking the engine but if you lock that bad boy up it will be over 500 amps! More than likely a very short duration spike won't effect things but you should get a handle on what's really going on. I myself would be very surprised if it only draws 10 AMPS, but am happy to be wrong. hook it up to a car battery so you have effectively unlimited amps for the motor and measure the current.

You also have to make sure you have enough amps for the motor because you risk burning it out if the voltage drop is too great, which will happen if you overload your power supply. Again this happens with starters. At 12V, it's fine, motor can spin fast. But if your battery is a bit dead and the voltage drops to say 9V, even though you would think that would mean less current draw (V=I x R), it will actually be more because now the motor is spinning much more slowly, and for a DC motor, speed is proportional to resistance. This is when car starters burn out. I'm only using starters as examples because I used to be an auto-electrician and that is where most of the repairs were done. Smaller motors didn't have as many problems, therefore I can't reliably quote figures for them, but the principles are the same...

[kahlid74]

To be REALLY sure what the motor does, you should get a car battery like Lilshawn says, and hook up an ammeter (or an induction loop thingo on a digital voltmeter) so you can see what the true current draw is- loaded and unloaded. Just remember that a DC motor draws STACKS of power at start up (because it has an effectively very low resistance) and at speed draws a lot less. For instance your typical car starter might draw 50 amps or so just free spinning, and say 200 amps cranking the engine but if you lock that bad boy up it will be over 500 amps! More than likely a very short duration spike won't effect things but you should get a handle on what's really going on. I myself would be very surprised if it only draws 10 AMPS, but am happy to be wrong. hook it up to a car battery so you have effectively unlimited amps for the motor and measure the current.

You also have to make sure you have enough amps for the motor because you risk burning it out if the voltage drop is too great, which will happen if you overload your power supply. Again this happens with starters. At 12V, it's fine, motor can spin fast. But if your battery is a bit dead and the voltage drops to say 9V, even though you would think that would mean less current draw (V=I x R), it will actually be more because now the motor is spinning much more slowly, and for a DC motor, speed is proportional to resistance. This is when car starters burn out. I'm only using starters as examples because I used to be an auto-electrician and that is where most of the repairs were done. Smaller motors didn't have as many problems, therefore I can't reliably quote figures for them, but the principles are the same...

Thanks for the great recommendations!  I'll definitely give this a go.

[kahlid74]

Sooo, it's been a while since I updated this.  Too much stuff going on but i finally got back to this.  While picking up grass seed at Menards I grabbed a car battery charger.  Hooked it up to my Relay/UP-DOWN button/On-Off Button and boom-shakalaka, it worked like a champ:





So I then had to decide whether I wanted an Arduino to power it or a Raspberry Pi.  I had one of these "PiFace" electrical boards that has 8 inputs and 8 outputs and two 10AMP relays built into it.  So I decided what the heck, lets build it on Pi.  So I'm going to use a 3.5" LCD screen as the main login screen and a USB numpad as the keycode enter system.

[lilshawn]

that sounds epic. I can't wait to see that in action!