Team 1339 is excited to be participating in the open alliance this year!
We’re a mid-level team hoping to share some useful information about our robots this season.
To kick off our open build, we’d like to share what we’ve been up to during the offseason. Since much of our offseason was spent planning and preparing for KCMT, we decided not to be too ambitious and instead focused on constructing a solid WCD drivetrain. The robot served as a training platform for newer students and will be used to quickly mount and test prototypes during the regular season.
Robot Images: (Apologies for vertical orientation)
We used Thrifty Bot COTS gussets to assemble the frame.
The robot features two custom gearboxes, with a pair of polycarbonate plates on each side. We’ve had great success using polycarb for similar gearboxes in the past, and so far these have held up great. Their gear ratios are 6.67:1
To transmit power to the outer wheels, we opted for 15mm wide HTD belts inside of our 2x2 drive rails. We 3D-printed some custom double pulleys for the center axle. The double pulleys sandwich around an 18t gear to avoid damaging their hex bores.
We’re strongly considering using GT3 belts and pulleys for our 2022 robot. Although they’re more difficult to source, their torque ratings are significantly better than those of HTD. If we do opt to use GT3, we’ll likely use a 5mm pitch so that we can quickly swap it with HTD if necessary
After uploading code and taking the robot out for a spin, it became apparent that it was drifting wayyy too much, so we swapped the rear omnis with another set of WCD traction wheels. After this change, it drove great.
To make this robot a more effective platform for testing code in the future, we threw a limelight camera onto it with some 3D-printed mounts. The mount was mostly inspired by this post, and is adjustable but can be firmly held in place by tightening the bolts at its pivot.
The last thing I’d like to share in this post is a design calculator that I’ve been working on. I mostly made it for fun but figured I’d post it here anyway in case any other teams find it useful.
1339 Design Calculator
These design tools greatly helped me make my own:
FRC Mechanical Design Calculator
AMB Design Spreadsheet
JVN Design Calculator
Once again, the CAD for this drivetrain can be found here.
Good luck in the 2022 season!