I have been thinking a lot about motor controllers lately, (believe me I am completely crazy) and I remembered talking to some teams during the competition season about the Victor SPX. Many teams remarked that the new Victor failed to fill any niche. All of these teams stated the Talon SRX was really the only choice when it came to CAN controllers. This was because the Talon was affordable for all the features it came with. Personally if my team is using PWM protocol, we usually use SPARK controllers as they extremely affordable and easy to use (wiring and programming). I fail to see what the Victor SPX offers to teams that they canât get with the Talon SRX. What has been your guysâ experience or what are the opinions about the Victor SPX?
Thanks,
Taggerun
Pros:
It is cheaper than the Talon SRX.
It weighs a touch less than the Talon SRX.
It is CAN based, like the Talon SRX.
It can be used with CTREâs CAN based sensors.
It can be used as a follower for the Talon SRX.
Cons:
It does not have a direct sensor input.
It hasnât been in FIRST Choice yet so the CAWst is not $0.
If we have a reason to use them in the future then we will.
I think the biggest benefit of the Victor SPX is the price, and the ability to use it as a slave with a Talon. As a team with a limited amount of hardware available (we reuse Talons every year), itâs great to be able to use a cheaper motor controller for the slave motors in a multi-motor gearbox, without having to dedicate an entire SRX to it.
I donât believe there is any functionality that the Victor SPX offers over the Talon SRX. The main difference is that the Victor is $40 less than the Talon. If you donât need the full functionality of a Talon but still need a CAN bus controller, a Victor can save you quite a lot of money.
I know my team (88) used them to control the follower motors on our drive. We use 8x 775 drive, so that saved us $240 with no loss in functionality.
The Victor SPX is absolutely a useful product and one that we will continue to use in coming seasons. This past season we used 4 Talon SRXâs and 9 Victor SPXâs. Itâs a marginally lighter, and much more cost effective solution when you donât need the âSmartâ Capabilities of the Talon. As such, our Drive used 1 Talon per side, and 2 Victors in Slave mode. Our elevator had 1 Talon, and 3 Victor slaves. Our intake used 2 Victors. We experienced no issues on either competition or practice robots and will continue with this scheme going forward.
Theyâve been our go-to for slave motors for a couple of years now. We mostly use Talon SRs for other functions which do not provide closed loop control because we already own them; every new controller weâve bought the last two years is CAN, either the SRX or SPX.
Yes, the Victor SPX is viable.
Do you have a time machine? The SPX just came out before the 2018 seasonâŚ
How do we get a time machine? Do you have a time machine sponsor?
I would add one more con: âit is not the dirt-cheapest motor controller availableâ. Whether thatâs valuable to a team will vary, but it is there.
That said, to OPâs question: SPX is 100% viable and Marshallâs assessment is right on target.
The Victor SPX was never meant to be a Talon clone. The âniche(s)â it fills are:
- Give teams a low cost entry to CAN motor controller
- Allow teams currently using PWM motor controllers to make the jump from PWM to CAN (and back) without taking on a significant financial risk
- Give current Talon SRX users cheaper, smaller, lighter weight option for non-smart mechanisms like intakes
As Tyler and others have mentioned, the master/slave mode on the Victor SPX and Talon SRX allows teams to save additional money. Why use a 6x Talons at $90/ea on your drivetrain when only one is handling any kind of sensor input? Instead, you could use 2x Talons and 4x Victors and save $160.
Using Tylerâs 2018 robot as an example, prior to the Victor SPX he would have spent $1080 on motor controllers to make his 2018 robot. However, thanks to the Victor SPX he only had to spend $720. Thatâs a savings of $360! Plus weâre not even talking about the 0.81 lbs he shaved off his robot weight.
Unless youâre looking at CAWST in which case the SPX is in fact an increase. I am assuming this will be corrected for 2019 because itâs a bonkers FIRSTism.
The SPX is viable, but only if you already have SRX controllers, IMO. Currently, the only âadvantageâ an SPX has over a SPARK by itself is that you get to use the shiny new CAN bus. As others have said, using it to follow an SRX is a way to save some money instead of using all SRX controllers.
My only gripe with the Victor SPX is the apparent lack of current monitoring functionality. Though I understand this is likely a factor in the cost difference between the Victor and Talon, itâs still a bit frustrating.
Beyond that, I like the weight benefits and ease of implementing into Master/Slave configurations with Talons. Being able to keep everything standardized to CAN without having to buy all Talons is nice, especially for motors that donât require sensor feedback.
We ran 4 on our bot this year, all as slaves to Talons or on mechanisms that didnât need direct sensors (i.e. intake rollers) Costs savings is the obvious advantage.
We didnât run them on our drive only due to not being super certain about how well the plastic casing would hold up in a drive train application. However, I do not see any reason not to run them in the future.
We used them last year for all our motor applications that did not require encoder input. This is because we could wire and program them basically the same as the SRXs, but could save like $200-300 with no real loss of functionality. If we had used sparks or SRs, we would have had both CAN and PWM wiring and programming, using the SPX just let everything be the same.
Thereâs also physical âadvantagesâ such as size and weight. Plus there are some under the hood features that donât require the use of a Talon SRX such as the ability to do motion profiling using CAN based sensors (like the Pigeon or an encoder on a CANifier) and being able to field upgrade the firmware as new features are added.
Thatâs understandable. We did quite a bit of thermal testing when we were exploring the plastic housing. This included constant 10-15A loads for several hours and 40A loads for 15 minutes. As you can see on page 12 of the Victor SPX User Guide the Victor SPX actually runs cooler than the old Victor SP for the first 8.5 minutes when running at a continuous 40A.
Bring up the thought, should FIRST figure out how to offer teams Talon SPX (for all CAN teams) instead of SPARKs in the KoP?
We were mixed CAN and PWM this year, but the intent was to move towards CAN. We used SPARKs for intakes, but could use Victors if those were in the KoP. The $20 more (for two) may be an issue and also, certainly, being subsidized/donated by REV vs what CTRE does in FIRST Choice (and in the kit).
I hadnât thought seriously about limit switches for Victor SPX (which IIRC doesnât have this functionality) vs. SPARKs that already have it. I suppose you can add limit switches with CANifier. I suppose there are instances where a few VictorSPXs and a CANifier might be a preferable solution.
I can vouch for this too, we put our drive system through more abuse than most (the 8 drive motors collectively spiked over 400A on multiple occasions early in the season from various loads), 6 of the 8 motors ran on Victor SPXs mounted to plastic mounts and we never had any issues with excessive heating on the controllers (though the motors obviously ran hot on occasion). :rolleyes:
We tried 1 SRX & 2 SPX per drive gearbox (on triple-miniCIM) and had trouble with what we thought was getting the current limiting to work in follower mode⌠ended up going back to triple-SRX ::ouch:: - need to revisit the topic outside of Build and see if we can tease out what was going wrong.
We used them elsewhere and they worked great. I love having everything on CAN, I love the tiny form factor, I love the low cost - not Spark cheap, but real close.
Victor SPX doesnât support current limiting.