Wheelchair-Mounted Frisbee Golf Disc Launcher

I served as the Logistics Manager and Electromechanical Engineer on my Senior Design capstone project through CU Boulder Mechanical Engineering and Design Center Colorado. We were sponsored by the nonprofit Quality of Life Plus to design and build a device that would allow disabled service members to once again play the game of frisbee golf through wheelchair mounting and independent head switch triggers!

Motivation

  • Quality of Life Plus (QL+) is a nonprofit that partners with University STEM organizations to build assistive technology for 2.2 million American military veterans and first responders that live with a disability

  • Our particular service members were interested in playing frisbee golf, but have very little physical mobility and limited upper-extremity dexterity

    • They are patients at Craig Hospital, a world-renowned neurorehabilitation and research hospital in Denver that hosts hobby-based outings

  • Our goal was to build a device that could launch a disc from a motorized wheelchair with an independent trigger

Design

  • Seat plate bolts to the motorized wheel chair and is connected to the launching device by a vertical seat post

  • 8020 frame supports polycarbonate and ABS housing

  • Spring pin, hole plate, and gas springs make up the angle-of-attack adjustment system that allows an abled assistant to set the disc’s exit elevation at the user’s discretion

  • User selects 1 of 8 distance settings using one head switch, signified by an LED indicator

  • Second head switch triggers the wheel to ramp up and the linear actuator to push the disc into the path of the wheel

  • Spinning wheel, directly driven by a BLDC motor, launches the frisbee through an arc-shaped track

    • Wheel system is on a spring and linear bearings to accept multiple disc sizes

  • Electronics are enclosed in a waterproof box mounted on the side of the launcher

My Contribution

  • Performed hand calculations, wrote Matlab script, and researched commercial launchers to spec motor and other electrical components like ESC, LiPo batteries, power switch

  • Wrote Arduino program to take head switch input to control linear actuator and BLDC motor for frisbee launch

    • Incorporated motor ramp up and 8 speed/distance options

    • Programmed safety limits

  • Manufactured connectors and cable extension as well as assembled electronics enclosure

  • Managed a team of 5 other students to complete project on time and with a budget of $2000 by organizing the project schedule and delegating action items

  • Served as point of contact between team and external entities like, QL+ client, faculty director, vendors (acquiring donations and student discounts)