By: Jerry Lui, Rickeisha Brown (Manufacturing Engineers):
Given the requirement of having the phone housed within the body of the rover the body must accommodate for the dimensions of the particular phone being used. In this case, a Samsung Galaxy S4 is being used as the camera for the rover and has the dimensions of 5.38”x2.75”x0.31” (1). Also, to be able to see through the horizontally placed camera a periscope will be used with a dimension of 13/16’’x13/16’’x1-1/16’’.
The top lid has a length of 5.5’’ which gives a clearance/play of 0.12’’. The top portion also has a slot to accommodate the periscope and is set to 1’’ (free space of 3/32’’ per side) to allow for movement and alignment of the scope.
Next, portions of the body was removed to reduce the weight of the rover with the sharp corners of the sections filleted with a conic rho profile. The conic rho profile (default solidworks value at 0.5) adds a smoother transition from the adjacent faces yet is able to keep close to the original shape of the cutout instead of having an extremely rounded corner.
Also, since we want to be able to access the phone quickly the top should be removable and to accomplish that without having seating issues both the top and the bottom has ledges that sit within each other. Tolerances will be given and set to 0.01574”or 0.4mm (2). The periscope gives a90°shift in the view so that we can see directly forward of the rover.
The side designs are simply easier to construct, since they are solely based on the top and bottom component configuration. The sides are also going to support the various housing of components such as: motors, batteries, 3dot board, and pcb.
As you can see by the figures above, the side components support the wheel axeling, from the motor to the wheel itself. The diameter of each hole measures 0.1” which is the diameter of our screws and our our rod components. This is the exact measure of the diameter of the rods and screws that are used for our rover.
The inner side features include ledges for the cellphone placement. The ledge is centered about the top measurement 5.50” and begins 0.53” from the top of the rover, consider the thickness of the cell phone, the periscope will sit just perfect outside of the body, with enough area to for viewfinder.