1 WP2.2 Progress Update Deliverable Inertial System Platform Tyndall

2 Below is the Tyndall hardware currently under investigation IMU Rev 1 433MHz Radio Transceiver Battery, Power Layer + 70g accelerometer

3 System Test in DCU –DCU testing performed in Tennis Ireland (Ciaran, Graham) –Point-to-point testing initially (1 IMU and 1 Receiver) Findings – 2 main issues –Latency - Approx 30 samples/sec max for the 2g accelerometer –Inertial Sensor Range Accelerometer range limited (+/-2g) – tennis app will need increased range (70g accelerometer available onboard) Gyro range limited (+/-150deg/sec) Magnetometers yet to be tested/explored for player orientation

4 Investigation of Identified Issues –Communications Latency –433MHz radio is main bottleneck –Now exploring use of new radio (1Mbps [NRF2401] vs 250 Mbps using current [NRF905] radio transceiver), possible range issues –Results in 100 samples/sec versus 32 samples/sec 3x improvement - currently modifying firmware to further increase throughput –Sensor Range –On-board 70g sensor can be used to increase accelerometer range –Now investigating increase of current gyro range (x4) and possibility of using new gyros (x8 improvement) –Use of previously developed code for computing heading will need to be incorporated and tested for suitability

5 Immediate Tasks: Finalize/write a Specification as soon as possible for: –What specific player movements need to be monitored? –Define appropriate node functionality and location on body –Mark Gaffney is visiting DCU Fri/Mon so would be a great to discuss and try to tie down above spec during his visit Augment and/or retro-fit higher spec inertial sensors where required (e.g modify gyro circuit) – if certain sensors not important, we can turn off, reduce latency and save power – the above spec is key to planning this Implement multi-node radio network –Possible issues – increased latency, merging of captured sensor data Questions