Update/To Do List

Front Arm
- enlarge thru holes on outer arm
- mount gears to threaded rod and output shaft

Back Arm
- weld pillow block
- press in bushings
- mount gears to rods
- turn down output shaft to fit bushings
- assemble planetary motor
- turn down axle rod to fit into bushings
- weld axle to outer arm

Base Plate
- waterjetting
- drill and tap for pillow blocks and motor mounts

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).

Update

After turning in our three parts to Davor, we have made a few design changes. Our wedge will now be made out of aluminum instead of plastic due to strength issues. Furthermore, we decided the motor needed to be mounted on the back of our outer arm due to size constraints.

MCM must be demonstrated in two days. We have machined the outer arm, inner arm, and pillow block (see pictures above). We need to waterjet the wedge on Wednesday, and need to lathe away part of our threaded rod. Finally, we need to fit our machine together (press fits, pins, etc.) in order to present our machine to Davor.

Update

We are currently in the process of manufacturing three parts for MS7 due November 19th. Our three parts will be our plastic wedge (made on the laser cutter), our outer, hollowed out aluminum arm (milled), and the top pillow block made out of stock aluminum 5/8 inches thick.

We have already made the engineering drawings, and have to match up our parts to the engineering drawings. The finished outer arm is depicted above.

Update

MS 6

Nov. 1 - Nov. 5

These past few days have been dedicated to MS6, engineering for our most critical module (MCM). We met with Davor this week to try to finalize what our MCM would look like. He pointed us in the right direction with a curved wedge design. We spent most of the day Thursday throwing around ideas and doing analysis, making sure that this route was the best one to take. We proceeded to create a solid model of our MCM, engineering drawings, a bill of materials, and a manufacturing plan. We met with Davor today, November 5th, to discuss our design. He looked over our drawings and model. Davor told us that we needed to include two more aspects in our engineering of the MCM: how we will mount our arm to our base plate, and nylon inserts in between the inner and outer arms to reduce friction and promote the sliding motion we need. We will add these aspects into our design, finish the solid model for assembly of our whole machine, and start manufacturing our MCM in the coming days.