Help Running SysID 2022 on Swerve with Single Drive Motor Modules

Hello,
We have been trying to run the SysID tool on to characterize to Swerve Drive on our 2022 Competition FRC Robot. Reading the wpilib documentation it explained that only the drive motor controls of the swerve drive can be characterized and the rotation motor controls would need to be restricted (blocked in a straight forward position). That is understood.

But we seem to be stumped right from the get go. It seems that SysID in 2022 is set up such that it assumes each Drive Module has a paired set of Drive Motors for each Drive Module. For our Swerve Drive System we are using Falcon 500 Motors. We have 4 Swerve Module Caddies. Each Module has a single Falcon for the Drive Motor and a single Falcon controlling the rotation of the caddy. But trying to configure the Drive System in SysID there is no way to specify which Motors are Drive and which are Rotation, because I assume SysID does not consider Rotation, only Drive Motors. Refer to the attached screen capture to for reference (by default there are drive motor pairs with no way to reduce to a single motor) :

Since we only have a Single Drive Motor for each Caddy Module, there is no way to select only one Drive Motor per Module (i.e. delete one of the paired motors). To get around this I, was assigning the same CAN ID to both the Left and Right Motor the the Pair, but this doesn’t sound right. Why does SysID always assume there is a Paired Set of Drive Motors for each drive Module? How do we get around this to use SysID for our swerve set up? Also, does it matter which Swerve Module you assign to which Motor Controller Pair (0 - 3)?

The documentation at: Introduction to System Identification — FIRST Robotics Competition documentation is lacking on these type of details.

Thanks

Typically you’d just have 2 left and 2 right motors for driving. By blocking the wheels from turning, you made a differential drive. The motor selection is setup for differential drive, and you have a the first one on the left and right, and then the second one on each side. Depending on where you block the swerve turning. So you only have two pairs. If you had a 6 motor differential drive you’d have 3 pairs, and so on. But to have a differential drive you need a left and right motor.

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@ngreen That makes sense. So just couple the drive motors on the front caddies as one pair, and the rear caddies as another pair. That makes perfect sense.

Thank You for clearing that up.

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