Hello Everyone, I’m never around here and the circuits world. I have done a lot of 12v projects in my lifetime working with a lot of automotive stuff and big into Solar now. I need some help on a model project where I’m getting to the electronics side and I’m lost. I was going to make this project RC but decided it’s size and how realistic it is I’m going to do a 110v power source transformed to 12v for ease of motors, lighting ect... so let’s dive in with some info for you guys.

I work in a coal mine running heavy equipment. I run what they call is a dragline, it is a huge piece of machinery that is a cable driven machine that digs out overburden. I want to build a scale model that operates for self enjoyment and it’s a hobby. Here is the machine: http://s7d2.scene7.com/is/image/Caterpillar/C765894?$cc-g$

I want to use a joy stick type like this: https://m.ebay.ca/itm/4NO-4-Positio...870307?hash=item236ce60923:g:8wsAAOSweWVXdh2b

For motors I want to be able to use any 12v motor just off of eBay that will be able to power my machine. I will need to run 3 of them for the actions of the machine. There will be the 2 joy sticks. Now what I’m looking for is speed controllers to give those motors forward and reverse functions as well be able to control speed on them all from the joysticks.

I keep finding controllers like this: https://m.ebay.ca/itm/12V-40V-10A-P...262165?hash=item2a722e4815:g:94sAAOSwPCVX9dHY

In my past history with speed controllers I know there will be a power connections on there as well as motor connections. What I don’t get is how to wire them back to the joy sticks and why is there a knob on the controller? I’m guessing to set your speed but I want to do that on the joy sticks or is that not possible?

I would even be happy with having a controller that will give me the functions of forward and reverse on the joy sticks and if I have to use a knob like that to set a speed I’m happy with the joysticks would be for forward and back wards and have one speed.

Thanks hope someone can help me out.

 

Hello Everyone, I’m never around here and the circuits world. I have done a lot of 12v projects in my lifetime working with a lot of automotive stuff and big into Solar now. I need some help on a model project where I’m getting to the electronics side and I’m lost. I was going to make this project RC but decided it’s size and how realistic it is I’m going to do a 110v power source transformed to 12v for ease of motors, lighting ect... so let’s dive in with some info for you guys.

I work in a coal mine running heavy equipment. I run what they call is a dragline, it is a huge piece of machinery that is a cable driven machine that digs out overburden. I want to build a scale model that operates for self enjoyment and it’s a hobby. Here is the machine: http://s7d2.scene7.com/is/image/Caterpillar/C765894?$cc-g$

I want to use a joy stick type like this: https://m.ebay.ca/itm/4NO-4-Positio...870307?hash=item236ce60923:g:8wsAAOSweWVXdh2b

For motors I want to be able to use any 12v motor just off of eBay that will be able to power my machine. I will need to run 3 of them for the actions of the machine. There will be the 2 joy sticks. Now what I’m looking for is speed controllers to give those motors forward and reverse functions as well be able to control speed on them all from the joysticks.

I keep finding controllers like this: https://m.ebay.ca/itm/12V-40V-10A-P...262165?hash=item2a722e4815:g:94sAAOSwPCVX9dHY

In my past history with speed controllers I know there will be a power connections on there as well as motor connections. What I don’t get is how to wire them back to the joy sticks and why is there a knob on the controller? I’m guessing to set your speed but I want to do that on the joy sticks or is that not possible?

I would even be happy with having a controller that will give me the functions of forward and reverse on the joy sticks and if I have to use a knob like that to set a speed I’m happy with the joysticks would be for forward and back wards and have one speed.

Thanks hope someone can help me out.

I think, in order to get motors running in both directions, you'll need h-bridges (1 per motor.)

It looks like the joysticks you've chosen are simple on-off switches. They won't give any indication of how far you've moved them, so you won't be able to use them directly for speed control. You could use a separate knob for speed control, or you could shop for different joysticks with analog position sensing.

If I were doing this project, I'd use a microcontroller (Arduino, etc.) for all the conversions. It could read analog joysticks for variable speed and directional control, while outputting both the pwm speed signal and the digital directional signals needed by h-bridge drivers. The downside of a microcontroller solution is that you have to do programming. The upside is that the circuitry you have to build is much simpler, and you have a huge degree of flexibility/control over machine behavior.

I'm sure this stuff can all be done with discrete components and logic circuits, but it would be a handful!

Hopefully some of the more experienced people here will join in with better advice than mine.

 

Thanks for the reply!

I thought so with those joystick that they would be just for direction without position on half throttle forward or 80% forward.

Now I know of most of what your talking about I’ve experiment with Arduino boards, but a lot of this is over my head and don’t want to make the machine too complex.

Like I said even if I can get the joy sticks wire to controllers that just give me the forward and back ect... and have knobs or something to adjust the speed just right I could deal with that. Get the speed so it’s just right when bringing the bucket in and out and then leave it and just run the machine in one speed. The speed controller should be able to handle me going forward and back to neutral and back forward to slow down.

 

If you're ok with that level of control, I think you can use those joysticks and a motor speed control like the one you linked to. It might be better to use one motor speed control per motor, both in terms of reducing the load on each controller, and also because it would allow you to control speeds of different functions independently.

The key as I see it would be two DPST relays per motor. I don't have time to sketch it right now, but I'll share a sketch as soon as I can. The basic idea is that each joystick output would drive the coil of a relay, and each relay would be switching BOTH legs of power to its motor (positive side would be the pwm output of your speed controller.) Two relays would feed each motor, but with reverse polarity, and only one relay per motor would ever be on at once.

P.S. There's probably a simpler way to approach this. Again, this isn't my area of expertise, but it's fun stuff to think about!

 

There are certainly radio control systems that can give you 3 channel full proportional control and motor drivers to go with them if you want a plug and play system.
For instance, motor controller: https://www.gearbest.com/esc/pp_618556.html

 

Here are some sketches of how you could combine the joysticks you linked earlier with PWM motor speed controller(s) and motors. The PDF shows two motors worth of controls with separate PWM controllers for each motor. A lot of users here don't like PDF files, so I've also attached an image file zoomed in on just one motor's controls:

 

[QUOTE="ebeowulf17, [/QUOTE]

Yeah simple is good I just don’t want to make this a huge complex system that when it fails if it does I’m pulling out a laptop trying to find the glitch in programming ect... I’m sure there would be simpler ways of doing this if I knew a ton about these boards and electronics.

So looking at your diagram I get the some of it but it’s little over my head lol. So you’ll have to help me a bit.

So my plan was to go with each motor would be one speed controller. That way I can control that motors speed separate from the other motors and reduce load on the controller.

Now when you say DPST relay what is it and what’s its job? Is the motor driver the speed controller or the motor?

Do you have a link to these relays to kinda see what I’m looking at

 

There are certainly radio control systems that can give you 3 channel full proportional control and motor drivers to go with them if you want a plug and play system.
For instance, motor controller: https://www.gearbest.com/esc/pp_618556.html

Yeah I’m familiar with these, but usually these have to be hooked into a radio controller

 

Yeah I’m familiar with these, but usually these have to be hooked into a radio controller

And that's a problem because?

 

Yeah simple is good I just don’t want to make this a huge complex system that when it fails if it does I’m pulling out a laptop trying to find the glitch in programming ect... I’m sure there would be simpler ways of doing this if I knew a ton about these boards and electronics.

So looking at your diagram I get the some of it but it’s little over my head lol. So you’ll have to help me a bit.

So my plan was to go with each motor would be one speed controller. That way I can control that motors speed separate from the other motors and reduce load on the controller.

Now when you say DPST relay what is it and what’s its job? Is the motor driver the speed controller or the motor?

Do you have a link to these relays to kinda see what I’m looking at

Sorry for any ambiguity.

My "motor driver" is your speed controller.

A DPST relay is a double-pole, single-throw relay. The two poles mean that each relay is effectively two separate switches, controlled by the one coil.

https://en.m.wikipedia.org/wiki/Relay

http://www.electroschematics.com/9605/dpst-switch-relay/

The reason they're needed is because we need to reverse the polarity of the motor wiring in order to reverse directions. A single switch (the joystick switch output for any given direction) can't reverse the motor polarity. You need double-pole switches to do it. Basically each relay turns a single-pole joystick switch into a double-pole switch.

If you trace out the connections in my schematic, you'll see that when you push the joystick up, that provides power to the coil (K1.1) on the top relay. When the coil is energized, that pulls together both sets of contacts (K1.2 & K1.3) which connect:

• Motor terminal A to ground
• Motor terminal B to positive voltage from speed controller

If you push the joystick down you energize the coil and close the contacts on the bottom relay, which connects:

• Motor terminal A to speed controller
• Motor terminal B to ground

I hope this explains the conceptual stuff. I'll be back shortly with some example relays and shopping tips.

 

Regarding relay selection, you could just as easily use DPDT relays, which may be more common, and just use the common and NO contacts, ignoring the NC contacts.

I can't guarantee that all of these relays are suitable, but this list at DigiKey should give you an idea of what I'm talking about:

https://www.digikey.com/products/en...09=20&pf_1409=21&pf_1409=23&pf_69=6&pf_69=897

When choosing relays, here are some things to check:

• DPST or DPDT contacts
• Coil voltage 12VDC (you did say you planned to run this all off of a 12VDC supply, right?)
• Switching voltage rated for at least 12VDC nominal. More is better. Don't confuse AC ratings and DC ratings. Switches are often rated for much higher voltages at AC than at DC. You need to be able to handle at least 12V DC.
• Coil current should be small enough that your switch (the joystick) can handle switching the coil on and off. I seriously doubt this will be a limiting factor, but I'd be remiss if I didn't mention it.
• Contact current rating should be more than the current your motors will draw. Again, more is better. If you have a 1 amp motor, there's no harm in having a 2 or 5 or 20 amp contact rating.

I'm probably forgetting something, but that should get you far enough along to see if you even like the basic idea.

 

And that's a problem because?

That’s a problem because I’m building s custom control panel where the joy sticks mount with switches ect...

 

You could disconnect the sticks in the RC and connect the ones on your panel instead. You could also, if you wanted, not use the radio and connect the transmitter signal direct.

 

Here is a driver that you can use with ebeowulf17's circuit from post #6.

Motor Speed Control, DC 20A Surge, 6-24V
http://www.mpja.com/Motor-Speed-Control-DC-20A-Surge-6-24V/productinfo/31566+MD

Wide range control uses PWM to vary the speed of DC motors. Remote adjustment pot (included) connects to board by a 12” cable to header pins. Terminal strip for power & Motor connections.
Input: 6/12 or 24VDC
Output: 20A max surge.

 

Here is a driver that you can use with ebeowulf17's circuit from post #6.

Motor Speed Control, DC 20A Surge, 6-24V
http://www.mpja.com/Motor-Speed-Control-DC-20A-Surge-6-24V/productinfo/31566+MD

Wide range control uses PWM to vary the speed of DC motors. Remote adjustment pot (included) connects to board by a 12” cable to header pins. Terminal strip for power & Motor connections.
Input: 6/12 or 24VDC
Output: 20A max surge.

So I could use that with any 6 or 12v motor, example: http://www.mpja.com/12VDC-100-RPM-Gearhead-Motor/productinfo/32206+MD/

I have the motors and speed controllers mostly figured out, but Ebeowolf17 makes a good point about my joysticks. Has anyone seen joysticks that will work better without less tickering? Or is the price of those just worth to put a few relays in to change the pols of power on the motors?

 

Yeah i get the jist of what your talking about with why I would need the relays to swap the pols of the motors to reverse them. 1 relay for each direction. Forward would need one and backwards would need one.

I would love to have power through the joystick in means of selecting speed of 25%, 50% ect... but to keep things down in cost and more simple I dont mind having speed controls where I can dial in the right speed and leave it.

Now like i said before, maybe I need to look at more joysticks.