DOCUMENTATION

DOCUMENTATION

 

The physical assembly of the robot rests on two aluminum sheets which are connected using 80/20 framing along the underside and help support the sheets while preventing excessive bending. Underneath these 80/20 supports are front castor wheels that allow the robot to turn. Also connected is the adapter for the two motors, which is connected to the rear of the robot which houses air-filled drive wheels. Above the aluminum base sits a box created with pieces of 80/20 that support the chair and protect the electronics, which sit inside of the box. The LiDAR sensor will sit on top of the robot above the headrest of the chair. This placement allows for maximum field of vision. A support that holds the LiDAR sensor above the user’s head is connected to the back of the chair. Inside the 80/20 box are two 3D printed shelf holders, as well as shelves and battery holders. These components allow for the electronics and the battery to stay anchored in place. Electronic components such as the speakers are to be glued to the side covers. There will be two PIR and two ultrasonic sensors on the front of the robot, one on the back, and one on the two sides. All PCBs are to be screwed directly onto the shelves in the box. Fans are to be screwed into the outside faces of the shelf holders. These fans will cool all electronic and battery components. The joystick and the biometric fingerprint reader are to sit on the right armrest of the chair, allowing for easy operation by the user. Motion components, mainly the motors, are screwed into an adapter that sits underneath the 80/20 supports. The wiring of the motors runs underneath the base plate and through a hole to connect to the motor controllers inside the shelf holders. PCBs to control the motors, along with the Jetson Nano and the PCBs for the power distribution and microcontrollers for the sensors, will also be placed on the shelves inside the box. The Jetson Nano acts as the brain of the robot while the microcontrollers control the robot and read input from the sensors. There is also a screen to the left of the armrest for the user to interact with and manually control features of the robot.

The physical subsystem includes the overall structure of the robot to hold and protect both the electronics and user. The motor subsystem includes the motor and battery connections and provides power and movement to the robot as a whole. The sensor subsystems control the movement of the robot and keep users safe while transporting them to their destination. 

Overall, the goal is to be able to safely transport users in a hospital setting without significant effort from nurses or patient care aides. The robot is designed for adults who fall in the 0-8.5 range on the Extended Disability Status Scale for Multiple Sclerosis. This range encompasses normal neurological function to those who are essentially restricted to a bed or a wheelchair.