Update

We completed our MCM for MS8 (see pictures above), have a solid model for our whole machine, and our currently wrapping up manufacturing for the whole machine. We are yet to determine how our bottom pillow block (for constraining the rod at the lower end) will be mounted (Bob said that he could not weld the pillow block to our outer arm).

We also need to determine what the end of our back arm will look like. This geometry is important as it will be pushing the balls. The back arm will rotate due to the 6-speed motor, and we will use the planetary gear box for extension, identical to our front arm (see pictures).

Furthermore, we realized that the gear connection we used for MS8 is not structurally satisfactory (see above) so we ordered new gears that will be more easily mountable. Finally, we discussed motor gear ratios for the back arm. We decided we wanted maximum torque for the 6-speed motor, and almost maximum speed for the planetary motor (80:1).