Proper way to measure track width for drive train with no gyro

[Twindadaz]

It’s not clear how to measure the track width for drive train setups with no gyro. The turns we have attempted have been inaccurate.

[Foster]

@Twindadaz - Can you post some more about what you are talking about and the robot. (Like the number / types of wheels, where they are, how many motors are driving them, what you are trying to do to make turns and what the issue is and finally, what language are you using?)

Lots of my teams use Modkit and are able to use the drive base and have it make “45 degree” turns.

[jmckenna]

Hi @Twindadaz In addition to what @Foster mentioned, we also have a Knowledge Base article that mentions how to find the Track Width if you are trying to set up your drivetrain using the VEXcode IQ Blocks device configuration. Hope it helps: https://help.vex.com/article/300-how-to-configure-a-drivetrain-motors-only

[Twindadaz]

The help section had the answer I was looking for ( measure from the middle of the front right to the middle of the front left wheels) thanks! The robot is using the standard 200mm wheels, our track width is 255 mm, gear ratio is 1:1. We put all of that into the drive train setup and then asked the code to do a 90 degree turn. It came up short with a total of 75 degrees turned. Everything is up to date in terms of firmware and vexcode version. Thoughts?

[jpearman]

Is this a 4 wheel robot ? If so, using track width alone is often not enough, that may be improved with a future version of blocks. For now, increase track width until the robot makes repeatable 90 deg turns.

[Twindadaz]

Yes it is a 4 wheeled pink and purple testament to girl-powered engineering

[tfriez]

The built-in “Drivetrain” features in VEXcode IQ Blocks are optimized for IQ Clawbot-styled robots with similar wheelbase. Ensure that your wheel size settings are correct and that your robot’s track size is property set from axle to axle.

At this time there are no plans to add a modifiable wheelbase setting in the immediate future, but we are always listening for feedback from the community on feature prioritization.

[rhowbot]

increase track width until the robot makes repeatable 90 deg turns.

Yes, you can just fudge the track width until the developers add wheelbase setting. And more drive motors, and omniwheels… And how about H-drive? And X? (Just kidding, sorta)