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Goal q Design and build an affordable prosthetic hand without sacrificing quality and usability. q Will be controlled using EMG technology and have haptic feedback. § Electromyography (EMG): The recording of the electrical activity of muscle tissue via electrodes. § Haptic feedback to notify the user how much force they’re applying when gripping object; allows for ability to adjust strength of grip. Current Results and On-Going Work References [1] “MeSH Browser.” U.S. National Library of Medicine, National Institutes of Health,meshb.nlm.nih.gov/record/ui?name=Electromyography. [2] Saladin, Kenneth S. Anatomy&physiology: the unity of form and function.McGraw-Hill, 2015. [3] http://inmoov.fr/ [4] https://www.scheckandsiress.com/patient-information/care-and-use-of-your-device/above-elbow-prosthesis/ [5] https://lakotaonline.com/about_us/what_s_new/cherokee__van_gorden_students_create_3_d_prostheti/ [6] https://www.ottobockus.com/prosthetics/upper-limb-prosthetics/solution-overview/michelangelo-prosthetic-hand/ Challenges q The servos we utilized drew too much current which rendered a battery pack inefficient. We plan to order less power-hungry servos to resolve this issue. Presently, we have made an adapter so the prosthetic can be powered off the wall for demonstration purposes. Motivation and Objective Methodology q There is no real middle ground when it comes to prosthetics; the affordable options (Figs. 1-a and 1-b) have very limited functionality and are cumbersome to use, while the advanced options (Fig. 1-c) have better features but are exorbitantly expensive. q Our objective is to make a better middle ground by making a prosthetic hand that has features commonly found in top tier prosthetics, while offering it at a price that the average consumer can afford. Cumbersome Limited by Anatomy Too Expensive The EMG Controlled Prosthetic Hand with Bio-Feedback Group #68 Sean Byju, Jonathan Olcheski, Jesse Gatling, and Alejandro Sanchez Advisor: Prof. Laleh Najafizadeh and Li Zhu We would like to thank our advisor Prof. Laleh Najafizadeh and Li Zhu for their guidance and continued support. Contact: {sb1107, jco71, jag548, aas325}@scarletmail.rutgers.edu q Successfully implemented control of the prosthetic hand (Figs. 5-6) using signals from muscles via our EMG circuit (Fig. 4.1) and PIC microcontroller (Fig. 4.2). A calibration circuit (Fig. 4.4) was added in order for the prosthetic to be easily adjusted for different users. The bio-feedback system (Fig. 4.3 and Fig. 11) and a third degree of freedom (wrist rotation) were implemented. Additionally, several selectable preprogrammed movements were added for further functionality (Figs. 7-10). q We plan to place all our components on a PCB (Fig. 12) and also make a consolidated portable battery pack. (b)[5] (c)[6] q Build EMG circuit to acquire signal from the users muscle. Signal acquired via electrode patches. q Programmed PIC microcontroller in assembly to process signal from EMG and actuate hand correspondingly. q 3D print hand using open source design, assemble with servos and high tensile lines (used as tendons). q Add force sensors to finger tips and implement biofeedback using vibrational motors and PIC microcontroller. q Implement pre-programmed movements and “hold” feature for further usability. Fig. 5. Hand Being Controlled –“Open Palm” Fig. 6. Hand Being Controlled—“Clenched Fist” Fig. 7. –“Point” Fig. 8. –“Peace” Fig. 9. –“Okay” Fig. 10. –”Shaka” Fig. 11.– Force Sensors for Feedback System Fig. 12. – PCB Design (a)[4] Fig. 4.1. EMG Fig. 4.3. Bio-Feedback Fig. 4.4. Calibration Fig. 4.2. PIC Microcontroller Fig. 1. Examples of existing prosthetic hands
