Motor Controllers

[JPBlacksmiths]

So this is a question that I have had for a few years now, and never really gotten a good answer to it:

Which motor controller is the best for which situation? Meaning is there specific applications were one controller is better then the other, or is there just one motor controller which is the best, period?

This question has resurfaced for me especially with the creation of the new motor controllers such as the spark.

Thanks,
JP
Co-Captain Team 806

[DaveL]

In 2013 we liked the Talon because chips and aluminum dust kept destroying our Jags. We also like the 888 because the fan is already installed.
Going forward we are trying out the new Talons with a CAN bus.

Would like to here from others on how they connect the Talon green and yellow CAN wires together. Vex sells a nice device but it's expensive and it takes up a lot of room.

Dave

[Ari423]

My personal favorite is the Victor 888, but I chose the Spark because it does basically the same thing, costs about half, and it's still available. I would say the only case where I wouldn't use the Spark or Victor is if I wanted to do built-in PID control, where I would use the Talon SRX.

I've used Jaguars a number of times (against my will) and all I can say is NEVER AGAIN. They take up a ton of room, are prone to breaking (I had one that screeched at me), using CAN is practically impossible, and therefore it doesn't do much more than the Victor 888 or Spark.

Originally Posted by DaveL

Would like to here from others on how they connect the Talon green and yellow CAN wires together. Vex sells a nice device but it's expensive and it takes up a lot of room.

Can you not just crimp or solder them (cue debate on crimping vs soldering)?

[JPBlacksmiths]

Originally Posted by Ari423

I've used Jaguars a number of times (against my will) and all I can say is NEVER AGAIN.

Ya my team also despises Jaguars

[GeeTwo]

At this point, I'd still have to consider the Talon SR my favorite, based on the number of motors and hours we have utilized them with zero mishaps. Spike relays would be second for the same reason (no mishaps, fewer hours, though you may not consider them a controller).

It didn't take much use of the Talon SR to send the Jaguars and Victors (a few each 884s and 888s) into our "unused parts" collection.

Being a bit of a "never buy serial number 1 of anything" guy, I have high hopes for most of the various controllers on this list, but none of them has become a favorite yet. I really like the features of the Talon SRX; if it proves to be robust it will probably top my list next year. The Victor SP, Spark, and SD 540 are all in a runoff to displace the obsolescent Talon SR, with cost, reliability, and limit switch capability as ranking factors to be determined. The Jaguar is my least favorite ever controller since becoming associated with FRC in 2012, squarely behind both the Victor 884s and 888s. Every one that the team ever owned has died a painful, stinky death. As much as we wanted to stop using them, we couldn't stop using these fast enough to get any of them out of use before it went up in smoke.

For the record: no vote cast, because my only solid decision among the controllers listed is not jaguar.
Edit:

Originally Posted by Michael Blake

Wondering why Victor 884/888 was left out of voting yet Jaguar was included?

--Michael Blake

Ditto Talon SR.

[Michael Blake]

Wondering why Victor 884/888 was left out of voting yet Jaguar was included?

--Michael Blake

[marshall]

Originally Posted by DaveL

Would like to here from others on how they connect the Talon green and yellow CAN wires together. Vex sells a nice device but it's expensive and it takes up a lot of room.

These JST-SM style connectors are a royal pain to crimp BUT are simply amazing for connecting the talons together:



They are locking. They are cheap. And they are small. Simply awesome.

Crimping guide here explains how to crimp them (and APPs as well): https://www.ebikes.ca/documents/GrinConnectorGuide.pdf

They are just small enough that they are a royal pain to crimp though.

EDIT: We got ours from here because I know someone will ask: http://www.aliexpress.com/item/Free-...352919222.html

[SoftwareBug2.0]

Let's look at this logically:
-There's no reason for a Jaguar to be anyone's favorite
-Some people have chosen the Jaguar as their favorite

Therefore, there is there must be some fraction of people who are answering randomly. We'll assume that the people who choose randomly choose each option with equal probability.

-At this time we see 4/22 people have chosen "Jaguar" as their favorite.
-There are 5 different choices for the poll

Therefore 4/22*5 should give us the fraction of people who are choosing randomly. This comes out to approximately 90%.

QED

[philso]

Originally Posted by Ari423

Can you not just crimp or solder them (cue debate on crimping vs soldering)?

We used the 2-position "0.100" Latching Polarizing Connectors" from Hansen Hobbies for the CAN wires on the Talon SRX's last year and had zero problems throughout the competition season plus the 3 or 4 off-season events. The pins can be crimped with the same crimper used for the normal PWM cables. We also crimped Anderson connectors onto the input and output wires so that the whole motor controller can be swapped out quickly and easily (did not have to) or it can be re-used as is. Just be sure to do a pull-test immediately after each and every crimp and to have someone else inspect the work (and repeat the pull-test) to ensure it was all done correctly. We coiled up the excess wire and tied it up neatly using small cable ties. The connectors for the CAN connections were contained within the loop, guaranteeing that no physical strain is put on the connection.

http://hansenhobbies.com/products/co...nlpconnectors/
http://hansenhobbies.com/products/co.../pt1in_lp_1x2/

[Alan Anderson]

Originally Posted by marshall

Crimping guide here explains how to crimp them (and APPs as well): https://www.ebikes.ca/documents/GrinConnectorGuide.pdf

One quick trick with Anderson connectors: it is
possible to remove the pin from the housing and
also to re-insert the same pin back into the
housing.
Simply take a small flathead screwdriver and use
it to lift the hook of the Anderson pin up and away
from the ledge inside the housing.
You can then pull on the wire and remove the pin
from the housing.
Because of this process you may actually end up
bending the hook upwards and it will sometimes
stay that way. In order to then reuse the pin in a
housing you will need to gently bend the hook
down until it is inline with the barrel of the
housing.

Even before I saw the last paragraph about bending the hook, I knew the instructions for removing the pin were wrong. You shouldn't pry the pin up. You just need to push down the spring (referred to in the document as the "ledge") in order to release the pin and let it be pulled out. This is true for the small Anderson connectors and for the large SB50 battery connectors.

[marshall]

Originally Posted by Alan Anderson

Even before I saw the last paragraph about bending the hook, I knew the instructions for removing the pin were wrong. You shouldn't pry the pin up. You just need to push down the spring (referred to in the document as the "ledge") in order to release the pin and let it be pulled out. This is true for the small Anderson connectors and for the large SB50 battery connectors.

Would agree with that but not my guide... I do think someone needs to create a similar guide for FRC's common connectors though.

[MrForbes]

Originally Posted by philso

We also crimped Anderson connectors onto the input and output wires so that the whole motor controller can be swapped out quickly and easily (did not have to) or it can be re-used as is

I wonder if the 2016 FRC rules will consider this a "FABRICATED ITEM" and disallow it's use, if it was terminated before kickoff?

So many fun things to consider....

[FrankJ]

Originally Posted by MrForbes

I wonder if the 2016 FRC rules will consider this a "FABRICATED ITEM" and disallow it's use, if it was terminated before kickoff?

The 2015 rules has a specific exception for wiring terminations to COTs devices. I would think the 2016 rules would have the same exception. We will see. As a robot inspector, this is not an area I would focus on unless told to anyway.

[philso]

Originally Posted by MrForbes

I wonder if the 2016 FRC rules will consider this a "FABRICATED ITEM" and disallow it's use, if it was terminated before kickoff?

So many fun things to consider....

It is always a risk when "future proofing" something. What you may have done one year may not be legal the next. At the very least, one can use these motor controllers on a practice robot with very little effort.

[GeeTwo]

Originally Posted by MrForbes

I wonder if the 2016 FRC rules will consider this a "FABRICATED ITEM" and disallow it's use, if it was terminated before kickoff?

So many fun things to consider....

It would have been allowed last year under R12c.

Originally Posted by 2015 Game Manual

R12 Physical ROBOT elements created before kickoff are not permitted. Exceptions are:

• A. OPERATOR CONSOLE,
• B. battery assemblies per R4,
• C. FABRICATED items consisting of one COTS electrical device (e.g. a motor or motor controller), connectors, and any materials used to secure and insulate those connectors

However, this exception was not included for the withholding allowance; if you wanted a pre-terminated controller as a spare part, it needed to be included in the withholding allowance.

Originally Posted by 2015 Game Manual

R17 At an Event, Teams may have access to a static set of FABRICATED ITEMS, not bagged per R14, known as the WITHHOLDING ALLOWANCE, that shall not exceed 30 lbs. to be used to repair and/or upgrade their ROBOT. The WITHHOLDING ALLOWANCE may only be brought into the Venue when the Team initially loads in at the Event. Items made at an Event do not count towards this weight limit.
For Teams attending 2-Day Events, these FABRICATED ITEMS may be used during the Robot Access Period and/or brought to the Event, but the total weight may not exceed 30 lbs. FABRICATED ITEMS constructed during the Robot Access Period and bagged with the ROBOT are exempt from this limit.
Items exempt from this limit are:

• A. the OPERATOR CONSOLE,
• B. any ROBOT battery assemblies (as described in R4).