Real-time Action Tracking System (RATS) Brett Newlin and Ryan Frazier

Design RATS is to be used by extreme sports companies and organizations to monitor an athlete’s performance in competition. Gather and transmit data in real-time using 3-axis accelerometers and a gyroscope. With this data we can determine speed, height of jumps, degrees of rotation and possibly many other metrics. This system will help judges make a more accurate analysis of an athlete’s performance. Athletes will like this system because it will help standardize performances, instead of relying on the biases of the judges. This system will also help the athletes improve their skills by giving them detailed feedback.

Summer X-Games 2005 Men’s Halfpipe Finals. An athlete starts his run and performs many tricks, including a 720. The judge is able to see real-time data to verify a “true” 720 was performed. Makes the proper decision based on what he saw and what the sensors recorded. Winner is determined not only on style and consistency, but also on statistical data. This system will help level the playing field by balancing any judges biases with statistical data.

Architecture Four major components. 3 Volt, 3-axis Accelerometer – measure ±2/6 g acceleration. 5 Volt, Gyroscope – measure rotations in degrees/second (limit 300 degrees/second). 3 Volt, Atmel16 – gather and store data from accelerometer. 3 Volt, Mica2Dot Mote – transmit data and convert gyroscope analog signal to digital data.

Architecture Cont. Construction. PCB 4 layer board design. Data flow. Digital acceleration data sent to Atmel16. Digital acceleration data sent from Atmel16 to Mote. Analog angular velocity sent to ADC on Mote. All data values transmitted from Mote on board to Mote at judging table. Radio Frequency transmission at 433 Hz at 19/38 kbits/second.

Design Goals Construction. Desired Functionality. PCB design and layout must be completed for submission. Assembly of PCBs will be done by us or by PCB manufacturer. Data Acquisition Programs. Desired Functionality. Fastest data acquisition and still be real-time. Low power consumption. Compact Size. Rugged. Minimum Functionality. Real-time data acquisition. Use of PCB design. If we can not meet real-time data constraint at full data resolution we will decrease the number of samples we take from the accelerometer and gyroscope to meet bandwidth needs. A large piece of this project that is beyond the scope of our design is the front end.

Burning questions Current Unknowns. Current Problems. Communication between Atmel16 and Mote. Communication between 5V gyroscope and 3V Mote. Power conversion from 5V source to 3V source to power everything. Can the Mote perform ADC conversion of analog signal and transmit data? Current Problems. Voltage Regulators – 5V device can’t talk to a 3V device. Needed Advice on…. Voltage Regulators. Communication Stack. PCB design and layout.

Evaluation Evaluation should be based on the following metrics. Real-time transmission of reliable data. Compact design that can withstand extreme sports conditions. Product lifetime. Can this be upgraded to version 2.0? Important Tests. Accuracy of data. Strength of hardware. Real-time transmission. Useful information from user studies. Does the sensor inhibit your performance? Is the data useful? Is the data accurate?

Related Work RATS – by Matt N. Nevitt, Kabir K. Shahani, Brandon S. Tengan, and Geoffrey R. Velasco from the Information School. Real-time action tracking system for skateboard, snowboard, skiing, etc… events. Used a 2-axis accelerometer and an Ipaq to gather data. Everything was stored in a cage on the underside of the board. Use of break-beam systems to determine airtime. Our project is based on the same premise: Data acquisition of extreme sports. Our project is focused on a cleaner hardware system. Compact design as to not inhibit the rider. Addition of rotation data via a gyroscope. 3-axis accelerometer. Data transmitted in real-time.