The designing and building of the Data Wagon for measuring speed and distance
• CAD design of chassis, base, body and user interface panel
• Single 2mm carbide milling tool
• Material 12, 6 and 3mm plywood
• Machining tool paths calculated from drawing vectors, tool size and material dimensions
• Tool paths checked using the CAM simulator
• 3D pan and tilt gives an overall view of how the finished parts will look.
• Tool path data downloaded to the CNC controller
• Material size, thickness and tooling set up
• CNC Machining of parts to an accuracy +-0.025mm
• Finished parts
• Base and Chassis assembly
• Delrin chain drive from axle to encoder shaft
• Steel wheels and cast white metal axel boxes
• User interface panel and micro controller assembled into the wagon body
• Low cost micro controller using the ATMEL ATmega328 chip
• Optical quadrature encoder salvaged from an old PC mouse
• Resolution of 65 pulsed per revolution
• Dynamic C++ code
• Easily expandable to include any extra features that the customer may ask for such as speed measurement and data logging with connection to a PC via the USB port
• Initial test of the software, reading the outputs of the encoder and displaying pulse count and direction information
• Simple and uncluttered
• Clear LCD readout of distance in several formats