Senior Design Week 3: Mark Figueroa

This week, I focused entirely on the mechanical integration and final assembly of the robotic arm. After identifying performance limitations with the originally spec’d servos at the shoulder and elbow joints, I upgraded these locations to 35kg·cm torque-rated models to handle the increased load. I also printed out the reinforced the bicep joint using a double shear mounting system, replacing the original single shear design. This drastically reduced flex and improved overall arm stability. All remaining servos (base, wrist, and end effector) were upgraded to 25kg·cm torque-rated units for consistency. Once mechanical mounting was complete, I tested manual articulation of each joint to verify range and rigidity. The full arm assembly was then mounted to the chassis on a reinforced base plate and electrically connected in preparation for future control integration.

Figure 1: Robotic Arm Assembled

Separately, when testing the locking pins on the rocker bogie the 3D printed pins initially used to connect the rocker-bogie suspension arms deformed and snapped under the rover’s full weight. To resolve this, I replaced them with 12mm steel bolts from ACE Hardware, which provided a much more secure and durable mechanical interface.

Figure 2: Rocker Bogie Bolt