Mechanical

This year’s chassis model can be seen pictured below. All of the aluminum pieces have been CNC machined to reduce the overall weight of the rover while maintaining the structural integrity.
Features of this model include a central bar to mount the batteries on, multiple mounting surfaces, and a differential bar that connects the two sides of the rocker-bogie suspension. Also included are cover panels across the bottom and top of the chassis.
With this configuration, the cover panels and the support bars also act as mounting surfaces which allows the team to have more freedom in placing components on the chassis. The top cover panels are also readily removable to allow quick access to any of the internal components, like the batteries. The batteries are located where they are for stability and ease of access to them. The differential bar connects to the rocker-bogie suspensions on each side of the rover and to the rover itself. This allows the rover chassis to remain still while the rockers and bogies rotate to navigate difficult terrain.
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The above picture shows the current state of the chassis. Visible are the rocker and bogie of the left side connected to the differential bar along the back (right side of picture). The pin in the middle of the differential bar is what connects it to the rover itself. Also visible are the various electronic components mounted to the bottom cover panel and the batteries along the bottom bar.  The arm  mounts to the front left corner of the chassis and has a reach of 3 feet, as shown below.
The bottom section of the arm is moved by a linear actuator. This allows for the force from the arm to be absorbed better than with a motor attached to the base joint. The range of movement compared to a motor at the base is substantially limited with the use of the linear actuator, however, the range is still sufficient to complete its design functions.
The top section of the arm is operated by another linear actuator. The second linear actuator is attached to the top bar at the end while the bottom bar is attached at a point a few inches away. This allows the linear actuator to rotate the top arm. The combination of the two linear actuators allows for a theoretical “doughnut” shaped arc where the end of the arm can operate.
Attached to the end of the arm is the end effector. This is a series of three servos that control left/right, up/down, and rotation of the parallel gripper. The parallel gripper is controlled with another servo that allows of the arm to pick up and move objects.