4 motors

[chsrobotics3283]

What would you have to do if you want 4 motor controllers, with one joystick?

[Mark McLeod]

In Begin.vi do a

right-click-> Replace -> Robot Drive Palette

on "Drive - Open 2 Motors" to change it to "Drive - Open 4 Motors".

Then specify the 4 PWMs to be used.

[chsrobotics3283]

Ok thanks a lot thats what I thought at first.

[Integral]

The hardware option is to run 2 motor controllers via 1 PWM port and a PWM Y cable.

[grosh]

Originally Posted by Integral

The hardware option is to run 2 motor controllers via 1 PWM port and a PWM Y cable.

I don't think this is permitted by rule <R49> "Each power-regulating device (speed controller or relay module) shall control one and only one electrical load (motor actuator or compressor)"

We are also trying to change the 2010 Game Robot Project to drive with four motors & we have changed to Tank Drive. We have replaced the"Drive - Open 2 Motors" to "Drive - Open 4 Motors", but the robot is only driving with the same two wheels it drove with using the "Drive- Open 2 motor".

Is there another step we need to complete because we have also changed to tank drive?

I've attached a copy of our Begin VI.

Can anyone advise?

[Alan Anderson]

Originally Posted by Integral

The hardware option is to run 2 motor controllers via 1 PWM port and a PWM Y cable.

Originally Posted by grosh

I don't think this is permitted by rule <R49> "Each power-regulating device (speed controller or relay module) shall control one and only one electrical load (motor actuator or compressor)"

The Y cable connects one PWM output from the Digital Sidecar to two speed controllers. Each speed controller goes to a single motor; each motor comes from a single speed controller. <R49> is satisfied.

We are also trying to change the 2010 Game Robot Project to drive with four motors & we have changed to Tank Drive. We have replaced the"Drive - Open 2 Motors" to "Drive - Open 4 Motors", but the robot is only driving with the same two wheels it drove with using the "Drive- Open 2 motor".

Is there another step we need to complete because we have also changed to tank drive?

I've attached a copy of our Begin VI.

Can anyone advise?

The vi you posted looks right. My first thought is that perhaps you're not deploying the code to run at startup, and the cRIO is still running what was last loaded successfully. You might try to run the Robot Main vi (using the white "run" arrow) and see if it works that way.

[grosh]

Thanks for the clarification! The wiring option will work. Thanks again

[Doc Wu]

The Y-cable PWM adapters come in the KOP. I have used them in two past years.

We had two motors on each gear box. We absolutely did not want them to do anything other than exactly the same thing. Using the Y-cable keeps the program simpler, saves a PWM output and prevents a code mistake from possibly running the motors in different directions.

Whether you use the Y-cable depends on whether you need independent control of each motor, or whether they will be always working together.

They can save you some coding and spare a PWM output at the expense of some flexibility. It won't save you a motor controller, because as stated perviously, you still need one for each motor. You can do this with either Victors or Jaguars. (Although I wouldn't mix them.)