1 / 25

A MYOELECTRIC HAND PROSTHESIS FOR WRITING ENGLISH ALPHABETS

A MYOELECTRIC HAND PROSTHESIS FOR WRITING ENGLISH ALPHABETS. Ashish Sundar Co author: P. Prema (Senior Assistant Prof.) School of Bio-Sciences and Technology VIT University, Vellore Tamil Nadu India. Overview:. To develop : Low cost prosthetic hand

nishan
Télécharger la présentation

A MYOELECTRIC HAND PROSTHESIS FOR WRITING ENGLISH ALPHABETS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. A MYOELECTRIC HAND PROSTHESIS FOR WRITING ENGLISH ALPHABETS Ashish Sundar Co author: P. Prema (Senior Assistant Prof.) School of Bio-Sciences and Technology VIT University, Vellore Tamil Nadu India CEMI-2010, CSIO, Chandigarh

  2. Overview: To develop: • Low cost prosthetic hand • Capable of writing English alphabets with a pen • Sensing the EMG of identified, available arm muscles • Work done for writing four letters, “L”, “I”, “V” and “E” Source: http://www.shadowrobot.com CEMI-2010, CSIO, Chandigarh

  3. Block Diagram: CEMI-2010, CSIO, Chandigarh

  4. Sections: (EMG chara.) (filter chara.) (circuit dia.) (circuit dia.) (results) CEMI-2010, CSIO, Chandigarh

  5. Microcontroller section: VIT University, April 2010

  6. Servo working: 0.5 ms pulse train – rotate the shaft anticlockwise, -90 degrees 1 ms pulse train – fixes the shaft at 0 degrees 1.5 ms pulse train – rotate the shaft clockwise, +90 degrees CEMI-2010, CSIO, Chandigarh

  7. Design of the Hand: (DOF) (design) CEMI-2010, CSIO, Chandigarh

  8. Character segmentation: (flow chart) CEMI-2010, CSIO, Chandigarh

  9. The Letters ….> CEMI-2010, CSIO, Chandigarh

  10. The whole setup CEMI-2010, CSIO, Chandigarh

  11. Conclusion: • A five fingered spring loaded tendon driven hand prosthesis was developed. • The hand which was developed with low cost materials and reliable methods has shown satisfactory results. • The current design can undergo further design modifications and can be made into much more sophisticated model in all aspects. • With the addition of more number of motors and tendons the functionality of the whole system can be increased by increasing the number of active motions. • The EMG circuitry which shown less noise immunity, can be made more immune with the use of proper shielding wires and proper electrodes CEMI-2010, CSIO, Chandigarh

  12. References: • Mechatronic Experiments Course Design: A Myoelectric Controlled Partial-Hand Prosthesis Project; Ton-Tai Pan, Ping-Lin Fan, Huihua Kenny Chiang, Member, IEEE, Rong-Seng Chang, and Joe-Air Jiang, Member, IEEE; IEEE TRANSACTIONS ON EDUCATION, VOL. 47, NO. 3, AUGUST 2004 • Algorithm for Robot Writing using Character Segmentation: Salman Yussof, Adzly Anuar, Karina Fernandez, Universiti Tenaga Nasional Jalan Kajang-Puchong 43009 Kajang, Selangor, Malaysia; PROCEEDINGS OF THE THIRD INTERNATIONAL CONFERENCE ON INFORMATION TECHNOLOGY AND APPLICATIONS (ICITA’05) 0-7695-2316-1/05 • Digital Butterworth filter for subtracting noise from low magnitude surface electromyogram: Roger G.T. Melloa, Liliam F. Oliveirab, Jurandir Nadal; ELSAVIER: COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 87 (2007) 28–35 CEMI-2010, CSIO, Chandigarh

  13. THANK YOU…. CEMI-2010, CSIO, Chandigarh (title)

  14. EMG characteristics : • An extracellular field • Generated when the muscle fibers extend along the length of the muscle • Duration of 3- 15 ms • Amplitude ranges from 20 – 2000 microV • Recorded using bipolar electrodes (back) CEMI-2010, CSIO, Chandigarh

  15. Bessel’s Filter chara: (back) CEMI-2010, CSIO, Chandigarh

  16. EMG circuit diagram : • Fourth order Bessel’s filter • Design of HPF • FC = fn / (2πRC) • Design of LPF • FC = 1 / (2π fn RC) CEMI-2010, CSIO, Chandigarh (back)

  17. Detector section: • Voltage threshold of 1V was given • Pulses equivalent to Vcc is produced when input crosses the limit • Design • V1 = (VCC x R2) / (R1 + R2) CEMI-2010, CSIO, Chandigarh (back)

  18. Algorithm of program: • Micro controller runs in two modes: • Time delay mode • To check ports • Interrupt sub-routine • To reset the motors to the starting position (back) CEMI-2010, CSIO, Chandigarh

  19. As DOF increases, the complexity also increases • Complexity increased by increase in the number of actuators Source: http://www.shadowrobot.com Single DOF robotic hands are also available CEMI-2010, CSIO, Chandigarh

  20. Source: http://www.shadowrobot.com CEMI-2010, CSIO, Chandigarh (back)

  21. Design of the Hand: • Spring loaded hinge mechanism • Integrated distal and middle phalanges • Thickness of 0.6mm for spring element[1] and 0.8mm for spring element [2] • PIP joint of forefinger activates y axis motion • MCP joint of thumb activates x axis motion CEMI-2010, CSIO, Chandigarh

  22. Five fingered hand with 2 DOF • Tendon driven mechanism • Has mainly two types of motion: • Active and • Passive • Made from cheap materials • Provision for increasing the DOF • Can be used as an universal hand CEMI-2010, CSIO, Chandigarh (back)

  23. Filter response: • Response of filter + instrumentation amplifier • Found to be satisfactory • The cut- off can be increased with the usage of higher order filters • A cut off of 50 Hz for high pass filter • A cut off of 500 Hz for low pass filter CEMI-2010, CSIO, Chandigarh

  24. EMG obtained: …Noisy signals… • EMG can always be affected by noise • Proper insulation or noise reducing cables should be used CEMI-2010, CSIO, Chandigarh

  25. Detector section: • Voltage detector output is seen as pulses • These pulses will be driving microcontroller (back) CEMI-2010, CSIO, Chandigarh

More Related