Swerve and Steer Module

[bmammen]

Originally Posted by Peyton Yeung

I made a small flat plate from aluminum (2" x 1.5") to mount an MA3 encoder and a 20t gear to make the steering 1:1.

Do you happen to have any pictures of the plate with the encoder/gear mounted to it? We're still trying to figure out how we want to handle the absolute encoders.

[Peyton Yeung]

Originally Posted by bmammen

Do you happen to have any pictures of the plate with the encoder/gear mounted to it? We're still trying to figure out how we want to handle the absolute encoders.

Here are some pictures of the setup.

The encoder has a 1/4" output so I took a 3/8" hex shaft, drilled a 1/4" hole in one end, slotted the hole with a band saw, and slid a shaft collar over the slot and voila. The encoder now has a 3/8" hex shaft which I coupled with a 3/8" hex gear with the same number of teeth so the feedback is 1:1. The whole plate has just 5 holes in it.

[Mark McLeod]

We also added a 1:1 encoder gearing, but 3d printed the gears. We were looking for a smaller footprint.

[sraque]

Thanks for mentioning us in your post Peyton! Yes, we had quite a bit of success with these modules this year. We also used the US Digital MA3 absolute encoders for wheel direction. The mechanical solution mentioned earlier is fine if you are OK with always setting up in the same orientation and don't care about putting one more task on the drive team. We chose not to do that, and our different auto routines ran best with different initial wheel orientations.

My only observation on these modules is that after a bit, the gears begin to chatter. The shaft with bevel gear can flex away from its mating gear on the wheel and result in slipped gears. We still did well with it. It also allowed us to get going with swerve very quickly. But I must also shout out to Apple Pi. Without their Labview swerve code, we would have had a really rough time.

[page2067]

Originally Posted by sraque

Thanks for mentioning us in your post Peyton! Yes, we had quite a bit of success with these modules this year. We also used the US Digital MA3 absolute encoders for wheel direction. The mechanical solution mentioned earlier is fine if you are OK with always setting up in the same orientation and don't care about putting one more task on the drive team. We chose not to do that, and our different auto routines ran best with different initial wheel orientations.

My only observation on these modules is that after a bit, the gears begin to chatter. The shaft with bevel gear can flex away from its mating gear on the wheel and result in slipped gears. We still did well with it. It also allowed us to get going with swerve very quickly. But I must also shout out to Apple Pi. Without their Labview swerve code, we would have had a really rough time.

We were psyched to hear that a team that did as well as you guys used our code as a basis.
Congratulations on a great year!
Our programming team will be posting our past year swerve update later this fall. Our code and some powerpoint that describes the basis for it are on our resource tab of our website.

We appreciate hearing from teams that find it useful.

[bmammen]

Originally Posted by page2067

We were psyched to hear that a team that did as well as you guys used our code as a basis.
Congratulations on a great year!
Our programming team will be posting our past year swerve update later this fall. Our code and some powerpoint that describes the basis for it are on our resource tab of our website.

We appreciate hearing from teams that find it useful.

It was very useful to our team! We look forward to checking out the update code when you get it posted as well. Thanks

[bmammen]

Originally Posted by page2067

We were psyched to hear that a team that did as well as you guys used our code as a basis.
Congratulations on a great year!
Our programming team will be posting our past year swerve update later this fall. Our code and some powerpoint that describes the basis for it are on our resource tab of our website.

We appreciate hearing from teams that find it useful.

Any idea when you might post last seasons code? Curious what changes you guys made, your bot was very smooth on the field!

[page2067]

Originally Posted by Mark McLeod

We also added a 1:1 encoder gearing, but 3d printed the gears. We were looking for a smaller footprint.

Mark:
Curious - how much backlash or wiggle does the steering have before the steering encoder feels it?

[Mark McLeod]

Originally Posted by page2067

Mark:
Curious - how much backlash or wiggle does the steering have before the steering encoder feels it?

There is nearly none between the steering motor gear through the plastic encoder gearing. There is some normal backlash between the metal-to-metal steering gear and the wheel module gear. I should mention that these swerve units were constructed based on the AndyMark design, but were not purchased units, so play in through the mechanism may be different than in the commercial units.

I'd need to test again for more exact measurement. I don't remember the original numbers, but they aren't anything that affects the operation.

[bmammen]

Originally Posted by Peyton Yeung

Here are some pictures of the setup.

The encoder has a 1/4" output so I took a 3/8" hex shaft, drilled a 1/4" hole in one end, slotted the hole with a band saw, and slid a shaft collar over the slot and voila. The encoder now has a 3/8" hex shaft which I coupled with a 3/8" hex gear with the same number of teeth so the feedback is 1:1. The whole plate has just 5 holes in it.

That may be the simplest solution I've seen so far, thank you so much for the information and pictures! We would also like to give a shout out to Apple PI for the great LabView code they created for Swerve, our programmers were able to use it for the base code on our off season bot.

[josesantos]

Originally Posted by Peyton Yeung

Here are some pictures of the setup.

The encoder has a 1/4" output so I took a 3/8" hex shaft, drilled a 1/4" hole in one end, slotted the hole with a band saw, and slid a shaft collar over the slot and voila. The encoder now has a 3/8" hex shaft which I coupled with a 3/8" hex gear with the same number of teeth so the feedback is 1:1. The whole plate has just 5 holes in it.

So the 3/8" hex shaft acts like a collet clamping onto the encoder shaft? That's a pretty neat set up!