The MK4i module inverts the motors on an MK4 module to a lower position where they are out of the way and better protected. Overall height and center of gravity are therefore lower. The MK4i module also moves the wheel further into the corner of the chassis for a wider wheelbase which results in a more stable robot. Because the wheel is moved into an area the frame would typically occupy, the MK4i includes a secondary plate to properly box in the chassis.
Other Highlights of the MK4i module include:
- On-axis steering encoder (zero backlash, module can be disassembled/reassembled without resetting encoder offset)
- All plates made out of 7075-T6 aluminum
- All steel gears
- All moving parts are protected under top plate
- Includes secondary plate to box in frame
- 10-32 mounting holes on main plate for other robot subsystems
- Encoder guard to protect the steering encoder
- Same frame-to-floor height as previous Swerve Drive Specialties modules
- Same L1 - L3 drive ratios as the MK4 module
- No 3D printed parts
- Cable-tie “nubs” keeps cable-ties in place
- Bottom and top mounted chassis options
- Includes wheel tread cut-to-length, drilled, and pre-installed on wheel
- Includes all hardware, including hardware to mount module to robot
The MK4i module has many parts in common with the MK4 module. Kits to convert the MK4 to MK4i are available.
NEO V1.1 motors or Falcon 500 motors are compatible with the MK4 module. CIM motors are not compatible with the MK4 due to their larger diameter. The MK4 module is available with either NEO 8mm bore pinion gears, or Falcon 500 spline bore pinion gears.
The steering gear ratio of the MK4i is 150/7:1. The MK4i is available in 3 different drive gear ratios. The table below shows the drive gear ratios and free speeds with NEO V1.1 and Falcon 500 motors. L1 and L2 ratios are the most popular ratios and are suitable for standard full weight competition robots. The L3 ratio is more aggressive and is recommended for light weight robots.
The module easily mounts to common 2X1 frame material. The module main plate typically mounts on top of the robot chassis, however, there is also clearance to mount the chassis on top of the module main plate to maximize ground clearance.
SDS MK4i Swerve Module, Falcons
SDS MK4i Swerve Module, NEOs