System Implementation

We discussed the basic design of our stair climbing robot, and decided to use an elevator mechanism and omnidirectional wheels for our robot.

This is the basic system design that we proposed for our mock up demo. We have our wheels and motors mounted on a wooden chassis, with a bin near the front of the robot to act as the storage compartment for our vacuum. The elevator mechanism on the back of our robot will be driven by a large, high torque motor to drive the robot up the stair.

For our first system demo, we created a basic CAD model for our robot.

We attempted to complete a prototype of the full elevator subsystem, which involves the linear actuator and the front two wheels. During elevation, the front wheels are meant to slowly crawl up the stair in front while the actuator pushes the robot up from the rear with its wooden, rubber-covered foot.

This is where we first encountered our issues with current distribution. When we powered both the wheels and actuator with the same source, the motors received the majority of the current, and trying to change the wheel speed in the code slowed the actuator as well. We fixed this issue for the demonstration by using separate power supplies, and both parts of the subsystem behaved as we intended.

For our mid-semester presentation, we put together a much more detailed version of our CAD file:

For our fourth system demo, we built a prototype mobility system that can handle all directions of movement, even with the heavy linear actuator attached.

We modified our elevator system, using two linear actuators now to improve the stabilization of the robot for climbing stairs.

We added our vacuum subsystem to our robot, which is being controlled by voltage regulators.

We completed implementing the movement and vacuum subsystems together, such that the robot is now able to vacuum while performing lateral motion. We also installed limit switches to demonstrate changing direction when reaching the side of a stair.

We built an acrylic shelf to house electrical components that would otherwise not fit on the chassis. This shelf sits four inches above the chassis in the front.