Lower Body Exoskeleton Powered by Epidermal Electronics Systems

The purpose of our design revolves around the concept of enhancing the human body through the use of a lower body exoskeleton. The most applicable demographics for our design consists of paraplegics and non-paraplegics. The various uses we hope to include would allow the user to: walk again, lift heavier loads with the ability to move forward, back and be seated. Although lower body exoskeletons already exist on the market, they still have shortcomings that prevent widespread use among the general public. Our hope is to improve upon the design of existing exoskeletons with the integration of epidermal electronic systems (EES) with a hydraulic systems; allowing more functionality with less human metabolic consumption. We want the system to do most of the work for the user; to further our vision of minimalistic effort. The system will function by utilizing skin surface electromyogram signals (EMG); sent by muscles in the forearms. The signals will be picked up by the epidermal attachments transmitting them wirelessly to a microcontroller, activating the exoskeleton motion. A rigid, yet flexible frame will support the hydraulic systems and electronic components. One to two hydraulic pumps will be needed for three cylinders. One hydraulic cylinder, per leg, will be attached from the hamstring to the calf muscle. The third will be located at the hip, lifting the leg close to a ninety degree angle. The process for completing the lower body exoskeleton is split into three components: the hydraulic system, the electronic components, and the EES “tattoo.” The first step involves creating a CAD design of the frame and hydraulics. Francis Azari will be welding together the frame and attaching the cylinders to these frame at a machine shop with the assistance of Forrest Baber and Karan Patel. Saswat Mishra and Juan Soto will work together to program the Arduino Microcontroller and wire it to calibrate the hydraulic cylinders. Lastly, the EES “tattoo” will be fabricated by Saswat and Karan, using UV-Lithography in the VCU clean room. Our method of achieving our goal consists of splitting up into smaller groups; allowing us to complete work more efficiently. In order to allow ample time to complete the frame of the exoskeleton, the mechanical and electrical work has been split into the fall and spring semesters, respectively. By late December, we want the frame and hydraulic system to be completed so that we may begin coding and fabricating the EES in January. If all minimum goals can be completed early, we hope to include more features that will enhance the functionality of the suit.https://scholarscompass.vcu.edu/capstone/1054/thumbnail.jp