Andymark rhino drivetrain discussion

[snoman]

R53 Each power regulating device may control electrical loads per Table 4-4. Unless otherwise noted, each power regulating device shall control one and only one electrical load.

one controller per motor is how i read it

[Greg Needel]

Originally Posted by snoman

R53 Each power regulating device may control electrical loads per Table 4-4. Unless otherwise noted, each power regulating device shall control one and only one electrical load.

one controller per motor is how i read it

Correct. It is 1 motor per motor controller. You can use a PWM Y-Cable (like provided in the KOP) to provide control signal to 2 motor controllers at a time.

[jls667]

Could I make a PWM Y-cable to control three CIM motors or really three motor controlers for the Rhino drive? Is there a better way to wire and program Rhino drive?

[Greg Needel]

Originally Posted by jls667

Could I make a PWM Y-cable to control three CIM motors or really three motor controlers for the Rhino drive? Is there a better way to wire and program Rhino drive?

The simple answer to this is yes (although it is recommended you use the same type motor controller for all 3 motors, 1 motor controller per motor).

Alternatively you could use 3 different PWM ports on your roborio, and make them function the same in code.

[jls667]

I thought using one motor controller for three CIM motors was not allowed.

[orangemoore]

Originally Posted by jls667

I thought using one motor controller for three CIM motors was not allowed.

You are correct. You have to connect each CIM motor to its own (ideally same) motor controller. However the control signal (ie PWM) can be split using a Y-cable to send the same control signal to each of the motor controllers.

[EricH]

Originally Posted by jls667

I thought using one motor controller for three CIM motors was not allowed.

It isn't.

What I believe he's referring to is that you want to have all three motor controllers be the same type. Different types have slightly different responses, and having the motors react differently in the same gearbox can produce "interesting" results.

[jls667]

Thanks for the clarification.

[eedoga]

Got our Rhino drive train in middle of last week. We have both sides assembled and should be done mounting them on the cross beams today. (We ran out of screws last night and somehow came up 4 short.

To be clear we didn't order the modules from Andy Mark, and instead ordered all of the parts from andy mark with the exception of the metal side plates. We got a local machine shop to cut those out on their waterjet. ( I so want one of those...) :-) We did this hoping to save some time on the order figuring that would be one of the things that would hold up production.

In any case, things actually went together really smoothly.

We are using sheet metal to mount the bumpers. I don't have any pictures, but Team 3238 was kind enough to help us out with the use of their CNC plasma cutter. I'll post pictures of those tomorrow.



Sorry it is so blurry. I was in a hurry when I took the pictures yesterday and seeing that they aren't in focus on my phone is obviously beyond me.

DB

[evanperryg]

Originally Posted by Zebra_Fact_Man

Anyone know how fast these threads are rated for / how fast you've got them to go? Anyone cross 15 ft/s?

I'm sure it's possible... you wouldn't really even need this kind of speed with how tight this field is. We discussed it the sunday immediately after kickoff, and decided that, with the cost of the rhino drive, if we bought it we absolutely had to use it. This wasn't a risk we were willing to take, on a drivetrain we've never tried before, that has yet to see competitive use.

[jls667]

It turns out my team wants to use Talon SRX with CAN signaling. Here is what I think needs to be done to run Rhino Drive:
1. Each Talon SRX would need a different id.
2. Each Talon SRX would need to be daisy chained.
3. Since my team want 3 motors on each side of the Rhino Drive, we will need 6 Talon SRX controllers.

How do I program 3 motors for left and 3 motors for right? Do I setup RobotDrive1, RobotDrive2 and RobotDrive3 each for 2 motors?

Thanks.

[cgmv123]

Originally Posted by jls667

How do I program 3 motors for left and 3 motors for right? Do I setup RobotDrive1, RobotDrive2 and RobotDrive3 each for 2 motors?

If you're using CAN, you can 'slave' two CAN motor controllers to output exactly what a third 'master' controller outputs/is commanded to output.

[AdamHeard]

Anyone willing to post video of a rhino at weight being t-boned by another full weight robot on carpet?

[jls667]

I found some good sample code.
https://github.com/CrossTheRoadElec/...25997ec38d3768

[Tom Line]

Originally Posted by AdamHeard

Anyone willing to post video of a rhino at weight being t-boned by another full weight robot on carpet?

A whole lot of teams are going to be a whole lot of disappointed if those treads slide off when pushed sideways.....