28-01-2015 10:31

lynca

Re: pic: Front View of 2015 Robot

Great CAD work! Thanks for sharing.

1. Are you running 6:1 reduction on 4" mecanums ?
2. What ratio are you running your lift ?
3. Why run belt/chain on two sides of your lift ? (instead of using a single chain/belt)

28-01-2015 10:33

notmattlythgoe

Re: pic: Front View of 2015 Robot

Quote:

Originally Posted by lynca Great CAD work! Thanks for sharing. 1. Are you running 6:1 reduction on 4" mecanums ? 2. What ratio are you running your lift ? 3. Why run belt/chain on two sides of your lift ? (instead of using a single chain/belt)

28-01-2015 11:26

Chris Mounts

Re: pic: Front View of 2015 Robot

It's one continuous belt wound by two motors. The thought is that it should provide more even lift and help avoid racking.

Lift ratios are 11:72 (CIM to gear) then 18:36 timing pulley to a 4" wheel.

We're at an 11:72 reduction to the 4" wheels. It's to fast. Fingers crossed that we can work something out in code. The alternative of having a second reduction wasn't practical in the design.

28-01-2015 11:38

RonnieS

Re: pic: Front View of 2015 Robot

Quote:

Originally Posted by Chris Mounts It's one continuous belt wound by two motors. The thought is that it should provide more even lift and help avoid racking. Lift ratios are 11:72 (CIM to gear) then 18:36 timing pulley to a 4" wheel. We're at an 11:72 reduction to the 4" wheels. It's to fast. Fingers crossed that we can work something out in code. The alternative of having a second reduction wasn't practical in the design.

28-01-2015 14:20

Chris Mounts

Re: pic: Front View of 2015 Robot

Wisdom of the crowd and experience. It seems like the target speed for this year is something less than 10 ft/s. This ratio should put us between 11 and 14 ft/s. Not terrible but a little fast. This is why I think our programmers can fix it in code by limiting max power to the motors.

Do you have this setup running? We ordered the wrong CIM gears and are waiting for the correct ones to arrive (hopefully today) before we can test drive it. If you do have it running, how is it going? Is it controllable? Our biggest worry right now keeping the bot from becoming a 120 lb wrecking ball to our partners towers.

28-01-2015 17:44

RonnieS

Re: pic: Front View of 2015 Robot

Quote:

Originally Posted by Chris Mounts Wisdom of the crowd and experience. It seems like the target speed for this year is something less than 10 ft/s. This ratio should put us between 11 and 14 ft/s. Not terrible but a little fast. This is why I think our programmers can fix it in code by limiting max power to the motors. Do you have this setup running? We ordered the wrong CIM gears and are waiting for the correct ones to arrive (hopefully today) before we can test drive it. If you do have it running, how is it going? Is it controllable? Our biggest worry right now keeping the bot from becoming a 120 lb wrecking ball to our partners towers.