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:
The MK4i module has many parts in common with the MK4 module. Kits to convert the MK4 to MK4i are available.
NEO V1.1, Neo Vortex, Falcon 500, and Kraken X60 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 the appropriate pinion kit for any of the above motors.
The full steering ratio of the MK4i is 150/7:1, passing through one gear pair, then a pulley pair using a 64 tooth belt.
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.