Final

Source Code on GitHub

System Architecture | Software Design | Electrical Design | Mechanical Design

Mechanical Design

The mechanical design for this demo was created in AutoDesk Inventor. The three main components of the design are the cradle, motor mount, and button servos.

Cradle

The cradle was designed to securely hold the Wii remote while providing enough room to slide the motor mount in around it. It is a very simple design, just a box missing the back and with most of the top open to make the buttons available to the button servos. The lines on the Wii remote model indicate where the cradle covers on the remote. This was explicitly designed so the top of the cradle would hold the Wii remote down while still providing room for the servos to operate without interference.

Motor Mount

The motor mount was designed to securely hold both servos in place while they pressed buttons on the Wii remote without allowing them to deflect while buttons were held down. The outside pieces of the mount slide into the cradle between the sides of the cradle and the ends of the Wii remote. They keep the mount from moving while the servos push buttons. The ribs on the shelf for the D-Pad servo provide strength to avoid flexing since it would otherwise only be attached by the thin wall of the shelf itself. The servo for the fire button is held in the U-bend in the middle of the mount. The pegs attaching the servo to the mount provide the strength required for the mount to maintain stiffness despite having a gap along the main length of plastic.

Button Servos

The servos used in this project were a pair of Dynamixel XL-320 smart servos. The servo for controlling the D-Pad (directional pad) was attached to the shelf on the motor mount and used a cross-bar with two wings to push both directions on the pad using one servo. The servo for controlling the fire-button was held in the U-bend in the middle of the motor mount and used a simple bar to push the button.