my team and i are researching about motor controlers and we found these three variaties which we don’t know a difference between them so i am seeking knowledge of the elders to make sense of this problem
Here is a quick overview of the differences
Connected via can
Connected via can
Has a port to add feedback (encoders)
Connected via PWM
They all work with DC Brushed motors, so it comes down to application and programming preference for choosing them. If two motors are working together, you should use all CTRE (talon/victor) or all REV (spark). Personally, my team uses victors everywhere unless we need an encoder input. So like for our drivebase we have 1 talon w/ encoder input and 1 victor per side. Hope this helps a bit, and happy to elaborate if needed.
To add on to difference between Talon’s and Victors. Talons have integrated PID control. For one to do PID control with a victor, you have sensor feedback go to the robo-rio, then back to the victor, which is slower.
Edit: The information I posted in this thread is incorrect. Leaving it here so following comments make sense, but please make sure to read the replies for accurate information.
Probably worth noting that this is referring to the Victor SPX, Talon SRX, and original SPARK specifically. Most people just say Talon/Victor/SPARK for simplicity, but there’s multiple variations on each motor controller, some dating back to the beginning of FRC.
Just a quick rundown of all of them:
Victor 883/884/888: The oldest motor controllers in FRC. PWM only, have a required fan, but they do the job for low load stuff. Replaced by the Victor SP.
Victor SP: A more modern PWM only motor controller, superseded by the Victor SPX and original SPARK
Talon/Talon SR: First fan-less motor controller. Replaced by the Talon SRX.
SPARK MAX: First (and only) independent brushless motor controller in FRC. Used to control NEO and NEO 550 brushless motors, as well as any future brushless motors REV may put out in the future. It also has Talon SRX-like control features built in.
It may be helpful to wrap back around to this question when we get closer to build season, or whenever you have something concrete you’re looking to design, and some other constraints on the parts.
For most simple cases, any of them will do the trick. As you start to do (or desire) more complex things, the selection between them (and other options) starts to matter more.
The line in bold is very important. If your team ever decides to use NEO motors, the only FRC legal controllers for those motors will be SPARK MAXs (not normal SPARKs).
Quick side note: all three of those controllers can be connected via PWM (if you wanted to), not just the Spark
Is this correct? I thought Victor’s could be configured to read sensor packets directly off the CAN bus. Still a bit more latency than a direct connection in the Talon, but not a round-trip to the Rio and back.
Correct. You can use any CTRE sensor as a feedback device via CAN to utilize onboard PID with the Victor SPX.
Just to clarify a bit, SPARK MAX is also usable for brushed DC Motors as well, not just NEO and NEO 550. If your team is looking to move to a “smart” motor controller for brushed motors, SPARK MAX is worth a look.
If you have any questions about REV specific stuff don’t hesitate to reach out to firstname.lastname@example.org. More than happy to help.
*Also, Victor SPXes lack current limiting functionality, meaning that for high-load mechanisms and drivebases you almost always want one of the “smarter” motor controllers to protect your motors from burning out
Also, (someone should verify what I’m saying) the SparkMax and TalonSRX have very similar feature sets though the Talon is more expensive by ~$20. Other than interoperability with the more developed CTRE ecosystem, I see no reason for the price increase.
That, and personally I find the REV API more comfortable - the CTRE API uses ridiculous units (ticks per 100 seconds or something like that?).
Generally this is on the money, but some notes:
- Victor SP was really only superseded by the Victor SPX; the SPX replaced it for the 2018 season, while the SPARK arrived for 2016 and was a competitor for two seasons.
- While made by different companies, I would consider the SPARK to be the spiritual successor to the Talon and Talon SR (the latter was last available for the 2014 season). The Talon SRX is a very different beast in a lot of ways (integrated wires, integrated sensor port, CAN communication, onboard PID).
- Arguably omitted: the Talon FX controller, which is integrated into the Falcon 500 motors.
Now, for @Manolo 's situation, the question is probably what to buy.
- First, wait if you can. FIRST HQ usually announces what controllers will be legal for the next year sometime in the fall, and anything that’s new will be announced shortly afterward. Nothing has ever become illegal in this process, but maybe something gets a new edition or gets a price change (for example, REV dropped the SPARK price a bit when the Victor SPX came out).
- Do you want to run NEO or NEO 500 motors? As of right now, it’s only the SPARK MAX for you.
- Do you want to run Falcon 500 motors? If so, don’t buy a motor controller for it because the Talon FX motor controller is built in.
- Do you value smarts in your motor controllers? If you don’t (and if you don’t want to run brushless motors like the above), the original SPARK is a ridiculously good deal.
- If you do want smarts in your motor controllers, REV (with the SPARK MAX) and Cross The Road Electronics (with the Talon SRX, Talon FX in the Falcon 500, and VEX’s Victor SPX) have sort of become the Coke and Pepsi of this industry. Both are reasonably mature ecosystems at this point and have their highlights. And you can run both on the same robot if you like (we did in 2020). It largely comes down to preferences and loyalties.
- Do you find yourself always out of electrical room? If so, I’d steer toward one of the CAN-capable options (SPARK MAX, Talon SRX, Victor SPX, or the Talon FX inside a Falcon 500). The SPX is the smallest of them (ignoring Talon FX), but all of them have a significantly smaller footprint than a SPARK or older models. We crammed a ton of controllers into a small bay of our robot this year, and we were only able to do it because of choosing smaller controllers.
If you know your pain points, we’re happy to steer you in the right direction.
I’ll add to this a bit more: the current control system made by CTRE (PDP, VRM, PCM) is being replaced in 2022/23 by a new system made by REV. Teams that bought into the CTRE ecosystem have enjoyed the perk of a single application to monitor all devices (Phoenix Tuner). REV is designing a similar application to accompany the new control system, so teams that buy into the developing REV ecosystem will enjoy said perk in 2022/23 and forward.
Having used both REV and CTRE components on our robot in 2020, I can say while it’d be nice if one app set up everything it’s honestly not that big of a deal. There are many other attributes that I’d put ahead of that (price, size, software support, supported motors, community knowledge of the controller).
But speaking of software on the PC, the SPARK MAX does have a USB-C interface that allows motors on a SPARK MAX to be spun up from a PC. We couldn’t quite figure out controlling multiples at once that way (PEBKAC is entirely possible there), but even for a single motor it’s handy.
I would have no problem running these under an extremely high load. The lack of built in feedback and only being PWM is the only reason I have many that could be had at a great price
There are also performance differences, and sometime reliability or ease-of-use also become important. Here are a couple of related threads if someone on your team really wants to dive into things (of course, there’s a lot more on CD besides, so search away!):
Don’t forget about the Tekin REBEL, both the Victor 883 and Tekin REBEL were in the kit of parts in 1999, and are the oldest motor controllers used in FRC. These motor controllers are now older than the students competing in the competition.
The Victor 884 came along in 2004, and the Victor 888 came along in 2009. It would likely be fairly difficult to find any of these older motor controllers from anywhere except established teams that still have some of these older robots around for fun.
They’re probably older than some mentors now… People probably knew that they would be used in the upcoming season before I was even born.
But yeah, I should have specified “oldest legal motor controllers”. I guess 883s aren’t legal anymore, but I think the 884 is still older than any other legal motor controller anyway.