Design of a Bluetooth Low Energy connected EMG Recorder
3 likes1,746 views
Design of a portable, mobile Bluetooth Low Energy connected Electromyographic Recorder for Serious Games. More information: http://blog.multimedia-communications.net/
Design of a Bluetooth Low Energy connected EMG Recorder
- 1. 息 author(s) of these slides including research results from the KOM research network and TU Darmstadt; otherwise it is specified at the respective slide 14-Jul-14 Prof. Dr.-Ing. Ralf Steinmetz KOM - Multimedia Communications Lab Design_of_a_BLE_EMG_recorder_Abschlusspraesentation.pptx Design of a Bluetooth Low Energy connected EMG Recorder Ferdinand Keil, BSc. Wirtschaftsingenieurwesen Analog-digital-converter Bluetooth Low Energy LiPo battery Power supply system Microcontroller
- 2. KOM Multimedia Communications Lab 2 A quick Reminder: Goal of the Project Analog-digital-converter Bluetooth Low Energy LiPo battery Power supply system Microcontroller Mobile phone Portable BLE connected EMG system
- 3. KOM Multimedia Communications Lab 3 Agenda Image: Jeff Victor (http://www.jeffvictor.com/images/good_bad_ugly.jpg)
- 4. KOM Multimedia Communications Lab 4 Hard- and Software Custom PCB Firmware for Teensy, using open-source libraries nRF8001 library (P. Stoffregen, Adafruit) ADS129X library (own work, Conor Russomano) Android App, using BTLE code by Tony Dicola AndroidPlot (Apache 2.0 licensed)
- 5. KOM Multimedia Communications Lab 5 Hard- and Software Basic firmware was implemented Communication over BTLE or USB App shows data of a single channel Offset is subtracted, gain setting
- 6. KOM Multimedia Communications Lab 6 Additional Achievements Rewrote ADS129X library for Arduino Export of readings to .wav file Live-display of readings Created two Python scripts
- 7. KOM Multimedia Communications Lab 7 Live Demonstration LIVE
- 8. KOM Multimedia Communications Lab 8 Major Challenges General Challenges 1.PCB Design: 4-layers, mixed-signal design, custom PSU circuit 2.Finding Arduino libraries that work on ARM 3.Getting started with Android Specific Problems 1.The RDATAC problem: cmd not accepted by ADS1298 2.The RESET pin bug: both pull-down and up resistor 3.The CS pin bug: ADS1298 interferes with SPI when off
- 9. KOM Multimedia Communications Lab 9 Mistakes & Disadvantages No real Show-Stopper
- 10. KOM Multimedia Communications Lab 10 Mistakes & Disadvantages But Low through-put of Bluetooth Low Energy Higher gain necessary to use full-scale of ADC Python not fast enough for more than a single-channel at 4 kSPS Signal is burried in noise and has a high offset Botch wire necessary to wake up Teensy from sleep mode
- 11. KOM Multimedia Communications Lab 11 Host-software in C/C++ Optimized firmware (e.g. compression) Benchmark of Android BTLE stack Optimization of Android App iOS App DSP in host-software / App Soft-shutdown to save battery Changing to ADS1299 (max. gain 24x) Replace Bluetooth LE with regular Bluetooth Designing a case Improvements & Future Work
- 12. KOM Multimedia Communications Lab 12 Acknowledgements This work was made possible through the use of Open-Source software: ADS129X library: Conor Russomano nRF8001 Arduino library: Paul Stoffregen, the Adafruit team and Nordic Semiconductor Arduino: the Arduino team Teensy 3.1 and Teensyduino: Paul Stoffregen Python: the Python team Matplotlib: John Hunter, Michael Droettborn, et. al. AndroidPlot: the AndroidPlot team BTLEtest: Tony Dicola OpenBCI schematics: the OpenBCI team
- 13. KOM Multimedia Communications Lab 13 Thank you for your attention! Any questions? Image: 息 Produzioni Europee Associati, Arturo Gonzalez Producciones, Constatin Film
- 14. KOM Multimedia Communications Lab 14 Contact Ferdinand Keil Ferdinand.Keil@gmail.com