A unique approach to overcome a mechanical challenge
To design and build an RC robot that can descend a post, pick up a passenger, and deposit them safely on the top shelf while using the least amount of energy. The robot must also fit within a 30cm x 30cm x30cm cube and complete the course in under 3 minutes.
Our final design featured a scoop attached to an aluminum rod that was bent to have 2 90 degree angles. The L-shape serves several purposes:
1. It allows the robot to reach and scoop up the passenger.
2. It allows the robot to rotate around the top shelf to deposit them.
3. It allows the robot to collapse together so it fits within the size constraints.
The scoop was controlled by a pan and tilt mechanism composed of 2 servo motors and was placed on a platform that was raised and lowered by a winch system. For our chassis that housed the gearbox and motor, we fabricated an aluminum bracket to hold onto the post.
On competition day, our scoop bot performed extremely well, using only 177J (the class average was 403J) and successfully completing the course in 49 seconds, the fastest time in our class. Our bot was also named to have the most unique grabber functionality (the rest of the teams used either a claw or elevator to pick up the passenger).
During our early ideation phase, we took on a "fail early, fail often" mentality and brainstormed numerous ideas to test for different mechanisms to accomplish our goal. Early ideas included a mouse trap to grab the passenger and an arm that extends down the post.
We tested our initial ideas using foam core and some metal parts. For example, we used foam core models to determine the appropriate size of the bracket opening so that the chassis would remain upright.
In order to determine if the scoop was a feasible design, we performed manual tests. We learned through our experiments that the passengers had a high center of mass, so we could position our robot to strike at their feet and cause them to fall backwards into the scoop instead of getting pushed forward off of the course.