[FRC Blog] 2017 Motor (and Servo?) Controllers and MXP

[Mark McLeod]

Originally Posted by EmileH

How come Analog Devices' ADIS16448 isn't listed as an approved device on the MXP, even though it is available in FIRST Choice?

FIRST gave us a list of legal MXP all-in-one active boards, not the individual devices we plug into the roboRIO expansion port or the 3rd party MXP all-in-one active boards.
What we plug into them is up to us.

[EmileH]

Originally Posted by Mark McLeod

FIRST gave us a list of legal MXP's, not the devices we plug into MXPs.
What we plug into them is up to us.

Ah, now I understand. Thank you.

[Bkeeneykid]

Another thing to consider is that this is only the approved list of active devices. Under R69 from last year, this is the definition of a active device:

An ACTIVE DEVICE is any device capable of dynamically controlling and/or converting a source of electrical energy by the application of external electrical stimulus.

The ADIS doesn't control and deliver a source of electrical energy, so it wouldn't need to be on this list.

[bobbysq]

Originally Posted by Rich Anderson

I am working on a prototype turret driven by a pixy cam, and am worried about the servo load on the pixy. Would the motor controller be the answer for an arduino server output too? I am thinking of using a parallel 12v to 5v power supply similar to the LED light hookup on the RioDuino. The servo power supply sounds neat if the game calls for servos this year (I would like to use the Smart servos, which we already have in our inventory).

It should be able to act as an output for any device. If I were to guess, it outputs +6V on the center rail and GND and signal are simply passed through.

Also, remember that in competition servos need to be controlled by the RoboRIO.

[Poppeseed]

Originally Posted by EmileH

How come Analog Devices' ADIS16448 isn't listed as an approved device on the MXP, even though it is available in FIRST Choice?

This list is only for active devices. My understanding from the 2016 rules (R68/R69) is that it's only considered active if it generates motion from the output pins. Something like the ADIS16448 is a sensor, and therefore flals under their passive device label.

You can read more from their blog in 2014 if you like, but rules may have changed since then.

[Joe Ross]

Based on the SD540C Library documentation (http://www.mindsensors.com/reference/FRC/html/Java/) it looks like the SD540C is just a CAN enabled dumb speed controller, rather then a Talon SRX competitor.

[bobbysq]

It appears to have a few "smart" features, like getting the limit switch and changing brake/coast while driving. Overall, I think I'd still pick the SPARK over this at the moment, seeing how it offers the same limit switch stop feature (it's not hard to code in anyway) and costs $5 less with the option of buying through Amazon Prime.

However, something to note is that the manual mentions encoder inputs and currently says:

Closed loop Control feature is not available in firmware at this time.
However, you can upgrade firmware of your device to use those
features as soon as the firmware is available.

If they can add this feature soon (and before Kickoff soon, people won't design for features they don't have) and it works well, then the Talon SRX may be seeing its last season of being the dominant motor controller.

[marshall]

Originally Posted by bobbysq

If they can add this feature soon (and before Kickoff soon, people won't design for features they don't have) and it works well, then the Talon SRX may be seeing its last season of being the dominant motor controller.

If.

[Michael Hill]

So I guess nothing came out of the BLDC motor controller being demoed by CTRE at CMP last year?

[Greg Needel]

Originally Posted by Rich Anderson

I am working on a prototype turret driven by a pixy cam, and am worried about the servo load on the pixy. Would the motor controller be the answer for an arduino server output too? I am thinking of using a parallel 12v to 5v power supply similar to the LED light hookup on the RioDuino. The servo power supply sounds neat if the game calls for servos this year (I would like to use the Smart servos, which we already have in our inventory).

Yes, absolutely. The Servo Power Module is designed to inject power to any servo and pass through the signal line. We do interface with the signal line to so you can read status of each channel via LED feedback, but if you are running a PWM signal this will just work.

It is designed to accept a voltage range from 9-20v. ( 7v is the brownout, but 9v is required to start) We just posted our quick start data sheet so people can dig a bit more into it. http://www.revrobotics.com/content/d...11-1144-QS.pdf

And Units are available now at REVrobotics.com and soon to Amazon.

[bobbysq]

Originally Posted by Michael Hill

So I guess nothing came out of the BLDC motor controller being demoed by CTRE at CMP last year?

I'm wondering about this too. Maybe they couldn't convince FIRST to legalize a variety of brushless motors in time? They could also have not finished it for FRC use yet, since it appeared to only have an input for the HERO board.

[JStein]

The Huskie Board is now in full production with virtually unlimited supply over the course of the season. Our inventory shown is "built and on hand", but most backorder quantities will be 3-5 days. The board is available here: http://playingwithfusion.com/productview.php?pdid=88

The Huskies will be releasing more content shortly, so stay tuned!

Happy New Year!
-Justin, Playing With Fusion, Inc