I used Solidworks' sketching tool to synthesize a 4-bar linkage that could place the aluminum plate onto the roofs. Needing to accommodate 2 different slope angles was a big challenge, but I reached a good design using geometric techniques.

When designing the linkage, I aimed to shorten the links as much as possible because this would require less torque and a simpler gearbox. 

With a working linkage geometry, I designed the linkage, its gearbox, and its support structure using Solidworks.

Because the ideal link geometries crossed each other, I designed the system so that one set of links would be on one sife of the support structure and one would be on the opposite side.

To increase simplicity, I designed a gearbox with only 2 stages. This lower-torque design was a rare choice among the class, but it was possible because of the short links I had designed which required less torque to lift the gripper.

 I 3D printed the parts from PETG due to its high strength and slight ductility which made it the perfect material for friction fits. 

I additionally designed a clip-in mount for an ultrasonic sensor that allowed it to be easy interchanged or moved to a different section of the robot.

Many of the shaft collars we were provided with were stripped and unusable, so I used friction fits to acheive a design that used as few shaft collars as possible.