As the lead designer in my Capstone group I designed and manufactured most custom parts. I also managed our BOM and inventory.
This project was partnered with Purdue Polytechnic High School and Endress + Hauser to make an assembly line workstation that exposes students to common mechanical practices. This project was in progress for almost 3 years, my group started working on it in August 2020 and delivered it in May 2021. The conveyor line features several e-stops, a barcode scanner, a color sensor, and several proximity sensors. The assembly line sorts cylinders (jars) in two different ways (height and color). Depending on what the system is sorting the jars will go down different shoots for different characteristics. For example, if it’s sorting height; the tall jars will go down the first shute, whereas the short jars will go do the second shute. Along with that lesson plans and thorough technical documents were provided.
The latch box allowed for easy collection of jars from the collection bins’ false door. There is a ring attached to the end of the piston that allows it to be pulled back, freeing the trap door and dropping all jars from the collection bin. A challenge that I had with this design was getting the piston in the box. Originally the tabs to stop the piston went all the way up to the cap, which led to a design change of lowering the tabs. This allowed for the piston to get in to the box but still stop the piston from falling out. This was 3D printed using PLA.
The conveyor’s arms were initially designed by a previous group, unfortunately, the center of gravity of the old arms was very far away from the motor arm’s axis and led to the motors burning out. The arm was updated to weigh less and have the center of gravity much closer to the motor arm’s axis. This was printed with ABS, in order to reduce the weight the infill of the body was reduced to 7% and the layer thickness was lowered to decrease the wall thickness. A canister for washers was added to the end of the motor end arm to counteract the moment on the other side of the motor arm’s axis. With the reduced weight and the counterweight, the arm was able to be placed on the motor and function efficiently. Unfortunately, it was too efficient, the motor keyed shaft tore through the key slot of the arm’s keyway. This led to a design change of adding an aluminum plate on the flat side of the keyway, the made it so the keyway is less susceptible to damage.