Andymark rhino drivetrain discussion

[AngryCalculator]

My team saw and bought two modules almost immediately after kickoff. I have seen many people mention how they are not totally necessary to over come the defenses. Post your thoughts here!

[MikLast]

they are delayed by about 2-3 weeks, in case anyone is wondering...

[MrJohnston]

We discussed numerous possibilities for wheels/traction/etc. last night - including the Rhino... There are less expensive ways to do the same thing, though we do think this is a great product....

[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?

[iSpotix]

Our team has gone against them, but also discussed creating our own with the 2-3 week delay. I don't think it would be that hard for a team to CNC frames and assemble the parts.

[techtiger1]

Just FYI belts/ pulleys typically have a 2-3 week turnaround time from most if not all suppliers. 1251 my team has done tank treads in both 2010 and 2012 so we've done quite a bit of prior searching.

[Robomarfa]

Our second-year team purchased these as soon as they were available on Saturday and were just told they will ship by Thursday. We are a young team with limited machine shop capabilities. Rhino drive looks like it can handle any of the defenses easily depending on robot height and mechanisms.

If we were building a high goal shooter, we might want something more stable (no pivot point) and more maneuverable. For weakening defenses, should be great.

[Oblarg]

Frustrated at the whole "out of stock by the end of the first weekend" trope rearing its head again with FRC suppliers.

Look, I know it's difficult. It's a small market and it's hard to predict demand, etc. But this can't be the best that can be done. It's hard/impossible to teach good engineering practice when you're forced to rush to make your drive choice in the first day lest you not be able to purchase the parts you need until halfway through build season.

[jls667]

I understand that 2 or 3 cim motors are needed for each side of the Rhino drive.
Is each cim motor connected to its own motor controller?
How would one program this in Java?

Thanks.

[JPBlacksmiths]

8 inch pneumatic work fine

[nandeeka]

Originally Posted by jls667

I understand that 2 or 3 cim motors are needed for each side of the Rhino drive.
Is each cim motor connected to its own motor controller?
How would one program this in Java?

Thanks.

Yes, each CIM motor is connected to its own motor controller. The programming of multiple motor controllers is no different than controlling one motor per action in Java. You just have to make sure that every time you set the speed for one motor, you also set the speed for the other motor, in order to ensure that they are always going at the same speed.

[IronicDeadBird]

These COTS treads ought to make for an interesting shift in what drive bases can do. I can't wait to see how people respond to the "threat" of them appearing.

[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.