The NEW Build Your Own Arcade Controls

Main => Project Announcements => Topic started by: yo1dog on August 20, 2018, 05:04:38 pm

Title: Rotating Upright (Name TBD)
Post by: yo1dog on August 20, 2018, 05:04:38 pm
I've been lurking around these forums a long time. I finally created an account in 2009 to announce my first overly ambitious and flawed upright cabinet design which would never see the light of day. Since then, there have been 3 other such announcements with a bartop being hastily built and soon after dismantled and another flawed upright design that only got partially built.

Today, I announce yet another upright design that may also be overly ambitious. Will it ever get built? I hope so! I've dreamed of owning an arcade machine since I was a little kid. This time, I am actually in a situation were it is possible. Instead of being a college freshmen living in a dorm room with no money, no shop, and no chance, I now have a house, some extra cash, a fully equipped wood shop, and a real chance at bringing an upright cab into the world!

My first consideration is accurate-as-possible recreation with as few gameplay affecting compromises as possible. This means a properly oriented CRT at native resolutions and dedicated controls. If I had my way, I would just build 3 or 4 cabs. But, the wife is not too keen on the idea. So, we gotta rotate.

First, the video. I am going with a CRT. I will most likely use a 25" CRT TV (Sony Trinitron). I currently have a 19" Sony PVM and a 27" Sony Trinitron that I have been testing with. I might get an arcade monitor if I can find one available locally in Austin, TX. It will be standard/CGA resolution. Why? I built a list of the 100 or so games I care about and nearly all of them were CGA. I can easily live without the ones that are not. If I get really lucky and a multi/trisync becomes available locally at a non-exorbitant price, I'll get that. Seems unlikely.

The CRT will rotate to support horizontal and vertical games. Or, if that proves unfeasible, I might be able to convince the wife to let me build 2 cabs: a horizontal and a vertical one. I won't be holding my breath for that.

Second, the controls. My list of 100 games require several control types: directional buttons, 2-way joy, 4-way joy, 2 player/dual 8-way joys, trackball, roller, spinner, lightgun, and driving controls. I don't want a gaudy, giant control panel, I don't want to crowd a bunch of controls together, and I don't want to compromise with spinning joystick handles or switchable restrictor plates. The solution is a rotating control panel. One side for the 4-way joy, one side for the dual 8-way joys, and one side for the trackball and spinner. I am willing to compromise and substitute the 4-way joy for the directional buttons and the 2 way joys and substitute the trackball for the roller.  I am not very concerned about driving controls. Playing racing games standing up in front of on an upright won't feel right anyway (except Pole Position). If I do decide to include them they will be modular.

Luckily, I have plenty of buttons, 8-way joys, trackballs, lightguns, and even coin mechs laying around from my previous failed/never started builds.

Third, the art/theme. I really like the idea of original/repo art rather than custom. I want my favorite arcade games represented in the artwork. This led me to the idea of having each of the 3 control panels sport the artwork of one of my favorite games. I extended this idea to the marque, bezel, and side art. I created a topic specifically for the artwork here (http://forum.arcadecontrols.com/index.php/topic,158017.0.html). Please, please let me know what you think and any suggestions you have! Here's the latest:

(http://i.imgur.com/yo0074rl.jpg) (https://i.imgur.com/yo0074r.jpg)(http://i.imgur.com/VHnhJ1Al.jpg) (https://i.imgur.com/VHnhJ1A.jpg)

(http://i.imgur.com/X6i6KeYl.jpg) (https://i.imgur.com/X6i6KeY.jpg)
(http://i.imgur.com/VW2gEwel.jpg) (https://i.imgur.com/VW2gEwe.jpg)
(http://i.imgur.com/0B8j48xl.jpg) (https://i.imgur.com/0B8j48x.jpg)


Finally, the build. The control panel will be an equilateral triangle with slightly extended lips. The front of the cab will be hinged so it can rotate forward to allow the CP to spin freely.

(https://i.imgur.com/Jql73WRl.jpg) (https://i.imgur.com/Jql73WR.jpg)


I was exploring ways of locking the control panel that was strong (for when someone inevitability pounds on the CP), had no play when locked (no wobbly CP, please), and could be released and relocked easily. I came up with the idea of using a draw latch or tension latch between the edge of the CP and the front cab. These are the kind of latches you find on mason jar lids. They actively pull together. I build a quick test stand a control panel out of scrap 2x4 and plywood.

https://www.youtube.com/watch?v=KK2Xa4psLp0&feature=youtu.be (http://www.youtube.com/watch?v=KK2Xa4psLp0#ws)

I'll get a better video up soon. It worked really well. The latch is a tiny, cheap one meant for a small box that I found at the store. Still, the CP was rock solid when locked with no wobble at all and it did not budge when I pounded on it. I want to get a real/more heavy-duty one that is also recessed.

That's it. What do you guys think!? It's gonna happen this time! Fifth times the charm!  :)
Title: Re: Rotating Upright (Name TBD)
Post by: Jimbo on August 20, 2018, 05:34:09 pm
Good luck - I hope you get yours finished before mine!!! :D
Title: Re: Rotating Upright (Name TBD)
Post by: meyer980 on August 20, 2018, 08:40:59 pm
God speed! It's definitely ambtious.

I'm curious, with a rotating CP like that, how does the wiring get out to reach the computer?
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on August 21, 2018, 09:16:17 am
Using a slip ring (https://www.adafruit.com/product/1195?gclid=CjwKCAjw8O7bBRB0EiwAfbrTh4_qPkWHhsB4duBfXR3KkoNZ2y-EmSFU-XNbIuBOp28R6j2EGFwAkxoCRkkQAvD_BwE).
Title: Re: Rotating Upright (Name TBD)
Post by: barrymossel on August 22, 2018, 07:18:01 am
Looks cool to me. I just don't think I would use some kind of latch in the front for that control panel. You might want to consider another way to fixate it as I don't think this will ever look good.
Title: Re: Rotating Upright (Name TBD)
Post by: Mike A on August 22, 2018, 07:20:51 am
This might give you some ideas.

http://1uparcade.rmfx.com/ (http://1uparcade.rmfx.com/)
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on August 22, 2018, 09:37:56 am
Thanks! I have looked through that project (and all the rotating cabs I could fine).
Title: Re: Rotating Upright (Name TBD)
Post by: Jimbo on August 22, 2018, 10:08:35 am
Are you motorising the CP rotation?  If free-wheeling, how are you going to stop people manually rotating it too far etc?
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on August 22, 2018, 10:28:43 am
I am considering automating the rotation. Currently it spins freely.

Not sure what you mean by "rotating it too far". With a slip ring (https://www.adafruit.com/product/1195?gclid=CjwKCAjw8O7bBRB0EiwAfbrTh4_qPkWHhsB4duBfXR3KkoNZ2y-EmSFU-XNbIuBOp28R6j2EGFwAkxoCRkkQAvD_BwE) you can spin it 'round and 'round all day without issue.
Title: Re: Rotating Upright (Name TBD)
Post by: Jimbo on August 22, 2018, 10:33:38 am
Ah ok... where will you mount the slip ring? and how will you be mounting the rotating CP unit to the cabinet?
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on August 22, 2018, 11:14:03 am
The slip ring prevents the group of wires from twisting around themselves. But, you still have to ensure the slip ring itself doesn't get twisted around something. This just means you can't have an axle that goes all the way through the middle of the CP (otherwise the slip right would get twisted around it). So, the CP will attach to the sides via bearings and short axles (probably some steel rods) on both sides like this:

Removed
Title: Re: Rotating Upright (Name TBD)
Post by: Jimbo on August 22, 2018, 11:20:20 am
But once the wires come out of the CP enclosure, won't they eventually get twisted around the axle if you just freewheel?

Sorry for the questions - I have a similar setup with my rotating CP project.
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on August 22, 2018, 11:39:57 am
Derp, I forgot. I actually had already thought about this and then forgot again lol. You gotta use a hollow, stationary axle like so:

(http://i.imgur.com/lJ2GCwI.png) (https://i.imgur.com/lJ2GCwI.png)
Title: Re: Rotating Upright (Name TBD)
Post by: Jimbo on August 22, 2018, 11:58:28 am
OK that makes more sense.  You're doing it a slightly different way to me so this will be fun to watch,  :cheers:
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on August 22, 2018, 01:10:01 pm
I've read through your whole thread. Maybe we can motivate each other to get it done  :cheers:
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on September 23, 2018, 01:33:52 pm
So I have been thinking about the CRT. Specifically the size. Most of the classics used 19" CRTs (right?). And most classic cabs were about 25" wide (mine is as well). However, a 19" looks small in SketchUp.

I have a Sony PVM 20M2MDU CRT (medical grade CRT with RGB input) I was planning on using, but now I am having second thoughts. I know 21" CRTs were sometimes used. Hmm.

Thoughts?

Edit: My cab is 25" wide. Oriented horizontally, there is ~5" on the left and right side between the viewing area of the CRT and the sides.
Title: Re: Rotating Upright (Name TBD)
Post by: Mike A on September 23, 2018, 03:18:41 pm
A 19 inch arcade CRT is your best bet. The extra space is what a snazzy bezel is for. There are tons of classic arcade games that look great with the 19 inch CRT.
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on September 23, 2018, 10:14:28 pm
I agree, Mike. :cheers:

I downloaded a bunch of arcade cabinet models into Sketchup and put them next to mine. I figured out why a 19" looks so small on my cab: too much vertical space. Although the height is about the same, the problem is a combination of my control panel being too low (2" lower than Missile Command and 6" lower than Defender) and the bottom of the marquee outreach not sloping down enough (mine is basically flat). This creates ~7" of empty space above and bellow the viewing area on my cab compared to the average of ~2-4" on the others.

Made a few quick changes and it looks much better already. Before and after:
(https://i.imgur.com/gtQnlIRl.jpg)  (https://i.imgur.com/iSUIFedl.jpg)
Title: Re: Rotating Upright (Name TBD)
Post by: Mike A on September 23, 2018, 10:50:31 pm
Yup. Much better.
Title: Re: Rotating Upright (Name TBD)
Post by: darthpaul on October 10, 2018, 09:39:03 pm
Can never get enough of rotating monitors and control panels. Keep up the good work and don't rush it.
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on October 20, 2018, 12:06:19 pm
I got a new idea for the locking the control panel in place. The reason the tension latch worked so well is because it pulls the front and control panel together. This provides a very strong hold while also eliminating any play. However, I want the locking to be automated and I couldn't figure out a good way to automate a tension latch. I saw a jewelry box lock and got an idea:

(https://i.imgur.com/5vTqgiE.jpg)

It is a rotating latch made from a smaller offset inside a larger circle. When the latch rotates around the center of the larger circle, the "walls" of the latch get thicker and the distance between the inside of the latch and the catch gets smaller. Eventually the latch and catch connect. Exactly like a tension latch, rotating further causes slight deformation of the latch and creates tension between the latch and the catch. This eliminates any play.

Because the latching motion is perpendicular to the applied force, attempting to pull the latch and catch apart causes the force to be a shear force on the axle of the latch and very little force is necessary to keep the latch engaged.

Also, this design does not require exact fit or much accuracy to work well.

I made a really quick and crude test. It works really well! Here it is in action:

https://www.youtube.com/watch?v=TWbtyTGuhQU&feature=youtu.be (http://www.youtube.com/watch?v=TWbtyTGuhQU#ws)
Title: Re: Rotating Upright (Name TBD)
Post by: Mike A on October 22, 2018, 08:59:25 am
That could work.

It looks like a window latch. You could just use one of those. It would be smaller and much stronger and durable.
Title: Re: Rotating Upright (Name TBD)
Post by: Ian on October 22, 2018, 09:05:44 am
Not trying to be a dick, this is simply a question. I've been here since 2007. There have been so so so many people saying they will build a rotating control panel. I can't for the life of me remember if anyone ever accomplished it? For a while there we were getting a couple a year but they never quite finished it. Unless I am mistaken?


Again this is meant not to discourage you, I want you to pull this off! Use it as motivation! Get this thing done.
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on October 23, 2018, 10:33:47 am
That could work.

It looks like a window latch. You could just use one of those. It would be smaller and much stronger and durable.

Window latch! Thank you! I knew something like this must already exist but I could not think of it. I will give it a try.

I actually created a very crude metal one and it also worked well.


Not trying to be a dick, this is simply a question. I've been here since 2007. There have been so so so many people saying they will build a rotating control panel. I can't for the life of me remember if anyone ever accomplished it? For a while there we were getting a couple a year but they never quite finished it. Unless I am mistaken?


Again this is meant not to discourage you, I want you to pull this off! Use it as motivation! Get this thing done.

Yea, it seems most people never finish. My guess is that most people underestimate the complexity and effort involved. Once they start hitting those road bumps they decide they don't really need a rotating control panel. A modular one or simply a larger/wider one is much easier. :dunno

I will do my best!
Title: Re: Rotating Upright (Name TBD)
Post by: Mike A on October 23, 2018, 10:39:48 am
You have to finish. I have too much time invested in watching your progress.
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on October 25, 2018, 09:27:48 am
Aight, Mike. I'll do it for you! Us Mikes gotta stick together.
Title: Re: Rotating Upright (Name TBD)
Post by: Arroyo on October 26, 2018, 09:28:20 am
What about an electromagnetic lock?  They are really strong and you wouldn’t have to worry about any mechanical issues, this one is cheap and can hold 600lbs of force:

(https://uploads.tapatalk-cdn.com/20181026/df6522303b026321e88a6a07cd4226ba.jpg)
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on October 26, 2018, 09:45:55 am
Thought about that. But there a few issues:

1. It's pretty big at 10"x2"x1".
2. Requires constant power usage.
3. Magnets interfere with the CRT.
Title: Re: Rotating Upright (Name TBD)
Post by: Arroyo on October 26, 2018, 09:54:13 am
Thought about that. But there a few issues:

1. It's pretty big at 10"x2"x1".
2. Requires constant power usage.
3. Magnets interfere with the CRT.

What about embedding the magnets into the end portion of your triangle (where the panel ends meet) and have the electric strip sit below inside your cab?  This might solve the interference and size issue.  Can’t do anything about the power usage though.
Title: Re: Rotating Upright (Name TBD)
Post by: Malenko on October 26, 2018, 10:27:09 am
Instead of endless spins why not limit it?

Is it that big of a deal to spin it down twice instead of up once for a 3 sided panel? If you physically limit the spinning isnt it easier to lock it? You could do it with a peg or cotter pin etc
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on October 26, 2018, 10:42:20 am
Not at all. I am fine limiting the spin if that is required. However, I am not sure how limiting the spin affects how the locking would work.

The problem with using pins/pegs alone is that everything will need to have pretty exact tolerances. Otherwise there would be some play.
Title: Re: Rotating Upright (Name TBD)
Post by: Jimbo on October 26, 2018, 11:06:45 am
I toyed with a tapered pin/solenoid locking system for mine.  I've kinda stopped thinking about it though for the moment.  Once I get the control panels wired up I'll get back to thinking about the locking!
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on October 26, 2018, 11:57:05 am
Speaking of limitless rotating, that reminds me that I found a better solution than using a slip ring: using a through hole/bore (hollow) slip ring like this one:
https://www.ebay.com/itm/Slip-Ring-Through-Hole-Dia-12-7mm-6-Circuit-10A-for-Wind-Power-Generator-/141818076779?_trksid=p2385738.m4383.l4275.c10 (https://www.ebay.com/itm/Slip-Ring-Through-Hole-Dia-12-7mm-6-Circuit-10A-for-Wind-Power-Generator-/141818076779?_trksid=p2385738.m4383.l4275.c10)

This kind of slip ring rotates around the axle. This makes it so you don't have use a short, hollow axle and instead you can use a solid one that goes all the way across.

It seems no one makes cheap hobby versions of the through hole slip rings. The linked one above for $40 was the cheapest I could find. :dunno
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on October 26, 2018, 12:01:57 pm
I toyed with a tapered pin/solenoid locking system for mine.  I've kinda stopped thinking about it though for the moment.  Once I get the control panels wired up I'll get back to thinking about the locking!

I also had that idea. The tapering allows for looser tolerances. I don't remember why I stopped going that route. Maybe I was still looking for a simpler solution.

I need to order some servos, actuators, and gears to start testing the automation of these ideas.
Title: Re: Rotating Upright (Name TBD)
Post by: JudgeRob on October 26, 2018, 07:49:51 pm
The rotating panel would be really sick!  But, I don't see how you are going to do endless spins.  How are you going to slip ring that many wires?  Even if you did only USB connections, it seems like you would need a few of them...

For locking, you could use a liner actuator.  They're strong as hell, but might be a little pricey. 

Could try a big solenoid too...

Good luck! 
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on October 27, 2018, 09:40:59 am
The rotating panel would be really sick!  But, I don't see how you are going to do endless spins.  How are you going to slip ring that many wires?  Even if you did only USB connections, it seems like you would need a few of them...

Yea it might not work out, but I'm gonna try! The plan is to put a USB hub inside the rotating control panel. This way I only need a single USB cable (4 wires) going into it. The slip ring I am looking at has 6. The other 2 could be used for power to the USB hub if needed.

EDIT: I should also mention that the most I should need going into the control panel is 2 USB cables. 1 for the i-pac4 (56 inputs) which covers all buttons and joysticks and 1 for the the opti-pac (6 optical inputs) which covers the trackball and spinner. 2 Slip rings would cover that.

I could also get the i-pac ultimate which would cover everything (but it's expensive and overkill).
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on November 01, 2018, 11:11:44 am
How do you allow for counter force in a gear train?

If the control panel is rotated with a motor/servo, how do I account for someone grabbing it or preventing it from rotating? I don't want gears to get stripped, I don't want it to be possible to pinch fingers, and  I want to be able to manually rotate the control panel if needed.

I thought about using a belt. Controlling the tension allows for controlling how much force can be applied before the belt slips. However, it seems like there is an easier solution.
Title: Re: Rotating Upright (Name TBD)
Post by: Jimbo on November 01, 2018, 11:21:34 am
I think you have to decide who's going to use it... if it's just you and close friends, is it enough to trust that they won't abuse it?  Or will it be on display at drunken orgy parties etc? :D

For my similar project, I was planning on it being software controlled (arduino or rpi).  It can be "homed" so it always knows where it is in the rotation cycles (it would "home" when it gets switched on) and where each stop point/CP is.  If you are software controlling it there is a lot you can potentially do... you could constantly check the force/speed, apply opposite motor rotation or adjust rotation power, apply a brake etc if exceeds limits.  There could be a number of options... also using the force/speed detection could save some fingers being chopped off ("I'm trying too hard to rotate this... STOP!").

Of course, the cab could als blurt out "STAND CLEAR - ROTATION IN PROGRESS" with flashing lights and siren sounds etc...  ;-)

Must admit I haven't thought about this for a few months as my other bartop has been higher priority for Christmas.  But hopefully it's given you a few ideas.

 :cheers:
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on November 01, 2018, 11:42:18 am
Kids will use it. So it will get abused and they will do stupid stuff with it. That said, I could child lock it so it won't rotate.
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on November 01, 2018, 12:13:29 pm
Welp, I feel silly. The solution is simple and now seems obvious: limit the motor.

Just use a smaller DC motor with slower speed and lower torque.
And/or lower the voltage to lower the torque.
And/or gear it to lower the torque on the control panel (side bonus: faster rotation)

The current to the motor can be monitored to detect a stall and cut power. Though, if you are running the motor at a lower voltage than it is rated for, a short stall shouldn't be able to harm the motor.

DC motors can also rotate freely without causing damage so rotating it manually should not be a problem.
Title: Re: Rotating Upright (Name TBD)
Post by: DaOld Man on November 01, 2018, 04:41:30 pm
Good work going on here. Ive often though about rotating panels, but never attempted it. A few people on here have though.
Will be following!
Title: Re: Rotating Upright (Name TBD)
Post by: Ond on November 05, 2018, 06:01:42 pm
This is a cool idea which made me think a bit how I'd approach it.  I wouldn’t use slip rings at all.  There's no problem with twisting a wire loom through 90 or more degrees. You could rotate the panels back and forth with a geared stepper motor (which are really precise) and allow enough slack in the loom for a bit of twist.  A solenoid driven locking pin could be combined with the code for the stepper.  Just ideas for you.
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on November 06, 2018, 05:43:56 pm
A solenoid driven locking pin could be combined with the code for the stepper.  Just ideas for you.

I was looking for a solenoid that would work but I am having trouble. Most of them have a short stroke at 10mm. I found this one with a longer stroke (35mm) but I would need to attach something to the spring side and I am not sure how I would do that. Any ideas?

https://www.banggood.com/DC-12V-35mm-Long-Stroke-Push-Pull-Solenoid-Small-Electromagnetic-Electric-Magnet-p-1217063.html?cur_warehouse=CN (https://www.banggood.com/DC-12V-35mm-Long-Stroke-Push-Pull-Solenoid-Small-Electromagnetic-Electric-Magnet-p-1217063.html?cur_warehouse=CN)
Title: Re: Rotating Upright (Name TBD)
Post by: DaOld Man on November 07, 2018, 05:38:51 pm
Is the panel going to have gears? If so you could possibly have the solenoid engage one of the gears to lock it in place.
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on November 09, 2018, 07:45:24 pm
It really seems like locking the front panel and the control panel together is the way to go because it is simple, works very well, is easily accessible from the front, and accomplishes locking both the front panel and the control panel at the same time.

Along this line of thinking, I had another idea for a locking mechanism: bolting them together. If you could turn a bolt that was threaded into the front with the head above the control panel, you could pull the front and control panel together (see diagram below).

I've been toying with automating this project so I purchased this (https://www.amazon.com/gp/product/B07556CZL1/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1) DC motor with a gear train and threaded rod attached. I didn't realize how comically small it was which is dumb considering they include a picture of it next to a coin. But, I tried it out anyway.

I made this little test setup:

(https://i.imgur.com/u3QaSVw.jpg)
(https://i.imgur.com/FzIrR5L.jpg)
(https://i.imgur.com/TMel8C8.jpg)

I routed a channel for the motor to sit in and prevent it from spinning then I cut the slit for the washers and stationary nut to go in. Doubling up the nuts at the end lock them to the bolt and prevent them from spinning freely. This results in the motor, rod, and end washer moving away from the base when turning clockwise and towards the base when turning counter-clockwise.

It seems to work pretty well especially for how tiny that motor is. It creates a nice tight fit and the force on the joint goes from the wood to the washes to the nut to the threads and not on the motor. Next step is to mount it to my test rotating control panel setup.

Here it is in action:
https://www.youtube.com/watch?v=BCvIdQxOE80&feature=youtu.be (http://www.youtube.com/watch?v=BCvIdQxOE80#ws)
Title: Re: Rotating Upright (Name TBD)
Post by: ark_ader on November 10, 2018, 12:48:26 am
All these ideas are great but unfortunately (as I am finding out on my new project) wood on its own is way too heavy. 

It needs to be lighter yet have the same strength to mount the panels (without wiggle), and then some plexi over the top.  Something like 4mm aluminum plate, layered between 9mm MDF and 4mm plexi.

Also there is a height restriction.  Rotation supplied by 3d printed gears and a drill motor.  It needs to run smooth.

I'm checking around some metal supply firms to see if there is any remnants as I will need only 5 panels (pentagon) which should give plenty of options.  I'll post my finds.

I'll be following this thread. Good work so far.  :applaud:

Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on November 10, 2018, 01:11:31 am
wood on its own is way too heavy.

Are you referring to the control panel? Do you mean too heavy to rotate? If it is balanced and on decent bearings it should take very little effort to turn. Heck, even my test setup which is just wood on wood turns easily.
Title: Re: Rotating Upright (Name TBD)
Post by: Jimbo on November 10, 2018, 04:43:35 am
Hey hey... all this prototyping is a great idea before you actually start doing it on the actual panels.  I still have the brake to sort out, but I'm clearer on the rotation....

It would be good to see a drawing of how your rotating panels sit in with this.

Keep it up mate  :cheers:
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on November 23, 2018, 03:47:48 pm
Bought myself some toys. No really. I bought some sets of LEGO gears, axles, motors, etc. to play around with.

I used them to prototype the automating of the front panel. Works well:

https://www.youtube.com/watch?v=rQulxF5zNkA&feature=youtu.be (http://www.youtube.com/watch?v=rQulxF5zNkA#ws)

First video shows the front panel itself. Second is a close up of the motor. Third shows how you can still manually move the front panel if needed.

This was a quick, crude test so tolerances are very loose. That plus the fact it is wood-on-wood creates a lot of unnecessary friction. Nonetheless, it still works well. You can see it struggle to retract in the second video. Again, this is due to the loose tolerances allowing things to bend and create a bunch of friction. After I took the video I added another gear for a 1.667 ratio and it worked better.
Title: Re: Rotating Upright (Name TBD)
Post by: Arroyo on November 23, 2018, 04:14:57 pm
Pretty cool.  I’m rooting for you to pull this off, would be epic.
Title: Re: Rotating Upright (Name TBD)
Post by: Jamesbeat on December 06, 2018, 10:07:30 pm
Welp, I feel silly. The solution is simple and now seems obvious: limit the motor.

Just use a smaller DC motor with slower speed and lower torque.
And/or lower the voltage to lower the torque.
And/or gear it to lower the torque on the control panel (side bonus: faster rotation)

The current to the motor can be monitored to detect a stall and cut power. Though, if you are running the motor at a lower voltage than it is rated for, a short stall shouldn't be able to harm the motor.

DC motors can also rotate freely without causing damage so rotating it manually should not be a problem.

When you're motor shopping, take a look at 540 motors for radio controlled cars.

They are an industry standard size, and about the right size and power for a task like this.

The real advantage though is the sheer variety.
They have been the standard motor used in RC cars since the 80s, so they are very widely available, and so are accessories such as gears.

Because they are so widely used, there are loads to choose from, and the technology is so mature that even the very cheap ones are pretty good.

They are also available in a wide range of 'turns', which will allow you to select the exact windings you want for the speed and torque that you need.

You could pair the motor with a cheap electronic speed control for an RC car to get the exact speed you want.

I hope this will help you avoid reinventing the wheel when it comes to the motor.
Title: Re: Rotating Upright (Name TBD)
Post by: yo1dog on December 08, 2018, 10:31:17 am
Great advice, thanks! Looking into the 540s now. Having no gear train would be optimal as it reduces complexity and it also allows easier manual operation of the load end. As you said, I am able to find many 540s wound for torque like this one: https://www.amainhobbies.com/rc4wd-540-crawler-brushed-motor-80t-rc4ze0001/p260759 (https://www.amainhobbies.com/rc4wd-540-crawler-brushed-motor-80t-rc4ze0001/p260759)

Let me know if my simplistic knowledge of brushed DC motors is correct: Higher voltage = higher speed. Higher amperage = higher torque.

Given that I do not require variable speeds, I don't have a need for an electric speed control, right? I could just use my adjustable power supply to find the right voltage and amperage and then buy an appropriate power supply.
Title: Re: Rotating Upright (Name TBD)
Post by: JudgeRob on December 08, 2018, 09:14:31 pm
Yeah, but you would have to turn the power supply off and on.  The speed control is a pretty easy to use affordable way to control the motor, even if it is just off and on.