HeartSavers Testing & Evaluation

1. Chris Hoffman Ryan Kellogg Mike Zizza March 28, 2007 HeartSaversTesting & Evaluation http://www.ece.cmu.edu/~ece549/spring07/team5/

2. Test Cases Project Concept: Wearable heart monitor: Electrodes in shirt, capture/process signal, send data wirelessly to smart phone Status update: Prototyped heart rate detection in MATLAB Bluetooth on smart phone JTAG for troubleshooting Gumstix Test Cases: Coming online (bootstrap use case) Shutting down gracefully (teardown use case) Transmitting data (between sensors, embedded hardware, phone) Data processing (accuracy, performance) Requests from memory Failure recovery

3. Performance Testing • What is latency between robostix and gumstix? • What is analysis algorithm latency? With arrhythmia v. normal input data? • What is analysis algorithm accuracy? (What % of QRS peaks correctly identified) • What is algorithm throughput? (# QRS waves processed/ second) • How consistent is sampling rate?

4. Testing process • We have a machine which will output a synthesized ECG signal • Use as source of known test data • Record test data in files for algorithm testing • Bash scripting to: • Initialize gumstix / robostix • Test communication paths • Perform algorithm unit testing • Test data for normal rhythm, arrhythmias, etc • Evaluate algorithm accuracy • Evaluate algorithm performance

5. Looking Ahead • Difficulties anticipated: • Making amplification circuit work well • Keeping good contact between electrodes and skin during movement • Managing algorithm latency and accuracy • Trickiest to test: arrhythmia detection accuracy • Lessons learned so far: • Don’t fry/brick boards • Miniaturized boards don’t have easy access to standardized connectors (ie, JTAG)

6. Questions ?