Maintaining perfect control of mecanums using encoders?

[Ether]

Originally Posted by jbsmithtx

So to create a balanced mecanum bot, we don't need a suspension?

If a somewhat flexible frame doesn't count as a "suspension", then you don't need a suspension.

I believe right now in our classroom we can rock the robot on the front left and rear right corners a wee bit...

That spells death for mecanum.

[magnets]

If it's only a teeny-tiny bit, it might not end up being a problem on carpet.

If it's a lot more, you can get creative with a car jack and some straps, and bend the frame into shape again.

In order for mecanum to work properly, you need equal force pushing down on each wheel.

[Ether]

Originally Posted by magnets

In order for mecanum to work properly, you need equal force pushing down on each wheel.

You need sufficient force on each wheel. The forces do not necessarily all have to be equal. Post 13.

[Gdeaver]

Over the years our drivers have had allot of fun having their way with Mecanum drive robots. BoB was the last fun. However back in 2012 I noticed a Mecanum drive that had some pushing power and more swerve like movement. I did notice a KOP gyro on the bot. I suspect they had a very tightly controlled closed loop system. First time I saw a Mecanum that I had some respect for.

[DELurker]

Originally Posted by Gdeaver

Over the years our drivers have had allot of fun having their way with Mecanum drive robots. BoB was the last fun. However back in 2012 I noticed a Mecanum drive that had some pushing power and more swerve like movement. I did notice a KOP gyro on the bot. I suspect they had a very tightly controlled closed loop system. First time I saw a Mecanum that I had some respect for.

I know that in 2012 lots of MAR teams saw 1370 use Mecanum wheels to push other bots about the field. However, we didn't have a working gyro or closed loop system. Most of our pushing came from the bot being 119.8 pounds!

[ekapalka]

I've been thinking about this a lot. Couldn't you, hypothetically, map the joystick value (from -1 to +1) to +/-[rate of the slowest spinning motor] and then run four continuous PID loops (using encoders) to attain that rate?