Figure 1. Electropaint.
Designers: Matthew Brown, Joseph Lee, Mary Pelling, Joshua Usoro
Client Coordinator: Melissa Scales
Supervising Professor: Larry Bohs
INTRODUCTION
The client is an avid painter with a neuromuscular disease that limits his range of motion. The goal of this project is to develop a device that allows him to independently access all areas of his painting canvas. The Electropaint is a custom easel actuated by a joystick and switch, which control two motors and a linear actuator, allowing translation in three dimensions.
SUMMARY OF IMPACT
This project will allow the client more freedom to independently paint with minimal outside assistance. The client’s father commented, “This is one of those ‘Big Bang’ moments…they have designed and delivered a product that will enhance my son’s life.”
TECHNICAL DESCRIPTION
The Electropaint (Figure 1) comprises a modified commercial workbench, a horizontal rail, a vertical rail, a vertical glide adaptor, a frame, an easel, two screw-drive motors, a linear actuator, a joystick, and a switch. The workbench is a Black & Decker Workmate 225 with two steel plates bolted to the step, preventing the device from tipping while in use.
The horizontal rail, modified from a commercial drafting table, is 32” long and has two clamps that allow it be attached and removed from the workbench. The entire easel is attached to the horizontal rail so that it can be removed from the workbench for easier transportation.
The bottom of the 36” long vertical rail connects to the horizontal rail such that the vertical rail slides in the x-direction. The top of the vertical rail rests on the frame and can pivot about the x-axis as the frame moves. The vertical rail attaches to a screw-drive motor, which powers horizontal movement along the x-axis.
The vertical glide adapter is13” wide and 16.25” long, connected to the vertical rail so it can move in the y-direction. The vertical glide adapter attaches to a screw-drive motor, which powers the vertical movement along the y-axis.
The easel frame is made from six 3” wide pieces of ½” thick pine, and is 32” in width and 36” in length. The frame attaches to the horizontal rail via three hinges, allowing it to pivot about the x-axis. The frame also attaches to a linear actuator such that the extension of the actuator rotates the frame from a horizontal position to a vertical position, as controlled by a large toggle switch.
The 24”x24” pine easel holds the client’s canvas. It is covered with a 24” × 24” sheet of acrylic to prevent the client from touching the motors. It attaches to the vertical glide adapter, thereby providing three dimensions of motion.
Figure 2. Client using the Electropaint.
A handheld joystick controls all motion through a 18M2 PICAXE microcontroller mounted on a custom-printed circuit board. Themicrocontroller translates joystick and toggle switch input to the two screw-drive DC motors for x/y translation, and the linear actuator for rotation about the x-axis. Transistors and relays provide high power output to drive the motors and actuator from the PICAXE. Limit switches mounted on the frame prevent the screw-drive motors from over-travel.
Figure 2 shows the client using the Electropaint. The cost of the components for the device is approximately $800.