Caster Chassis - “Cassie”
With a goal of improving mechanism prototyping, KnightKrawler has created a prototype chassis that mimics the dimensions of a swerve chassis with MK5 Modules in the corners, but instead uses casters. We affectionately refer to this caster chassis as “Cassie”.
With this chassis, students can design, build and prototype mechanisms and test them on a frame that exactly represents the final robot chassis.
The Onshape model for the chassis is publicly available.
Parts List
Top Corner Blocks (DXF)
Bottom Corner Blocks (DXF)
MK5 Left Module (STL)
MK5 Right Module (STL)
Caster Height Block (STL)
Bumper Mount (STL)
Casters
Tips
- The MK5 3D printed caps that represent the size and location of the swerve modules assume ¾” plywood is used for the top corner blocks of the chassis.
- For improved accuracy, consider using ⅛” aluminum plate for the top and bottom corner blocks. We found during our prototyping, the plywood introduced variance and some prototype parts were cut ⅛” shorter than desired. Double check your dimensions after assembling your chassis. Using a belly pan, even plywood, can also stabilize the chassis dimensions.
- To improve rapid prototyping, consider fastening 2x2 lumber to the inside of the frame. Students using plywood to test mechanisms can quickly screw to the 2x2 lumber to adjust heights and extensions.
- The chassis assumes a ¼” spacer will exist between the aluminum rails and the bumpers. Corner blocks include the spacer. The 3D printed bumper mounts include a ¼” spacer.
- Consider making a single-side bumper to attach to the frame. A bumper is likely a necessity for any game piece interaction, even if it is just to test how the chassis pushes away game pieces while driving.