Risk Management 

Heavy Middle Segment

In our three segment design, the middle segment is significantly larger than the front and back segments. We were concerned that the robot would have difficulty lifting the middle segment due to its weight. However, with the torque our lift motors provided and the strength of our rack and pinion assembly, this was not a problem.

Non-lateral Movement

We designed our robot to translate laterally, but we did not design it to rotate much. The idea was that the robot should not have to rotate much, and if it got pushed off course it would always be able to square itself up against a step to straighten out. We found that the unevenness of the stairs did affect the robot’s motion, especially with the small wheels we were using. We also found that the robot did not straighten itself out as well as we had hoped by pushing against the next step. Since we used two separate motors in the middle of the robot, we were able to perform maneuvers using these to help the robot get over bumps and straighten itself out better, although we could not achieve much precision in these movements.

Vacuuming Ability

We were initially concerned about the amount of suction a small hand vacuum would provide based on the locations we wanted to place our nozzles. In the end we were able to fit two small hand vacuums on the robot, which gave us a good amount of suction power. Our 3D printed nozzles also fit well to the vacuum tubes and we did not have much leaking air. We had planned to attach sweepers under the robot to push dirt towards the nozzles, but we did not end up using these. With the combination of having a nozzles on either side of the robot,