CHALLENGING OLYMPIC MEDALS – AN INNOVATIVE GNSS-BASED MULTI- SENSOR SYSTEM FOR ATHLETE TRAINING AND COACHING K. Zhanga, F. Wua, C. Mackintoshb, T. Riceb, C. Goreb, A. Hahnb, and S. Holthousc aSchool of Mathematical and Geospatial Sciences, RMIT University, Melbourne, Australia bAustralian Institute of Sport, Canberra, Australia cCatapult Innovations Pty Ltd, Melbourne, Australia KEY WORDS: Global Positioning System, Olympic Competition, Inertial Navigation System, Sport Application ABSTRACT: In preparing for Olympic competition, every detail is important. Athletes and coaches are not only interested in the physiological information, but also interested in the positional information. Physiological information can be relatively easy to obtain using relevant detectors. However, real-time high precision determination of the athletes' movement and the status of motion has been a challenging task. This contribution introduces the development of a smart real-time athlete monitoring and coaching system, which integrates a low-cost GPS, Micro-Electro-Mechanical System (MEMS) inertial measurement units (IMUs), magnetometers, wireless communication and other physiological sensors. Surveying, Positioning And Navigation (SPAN) group at RMIT University in collaboration with the Australian Institute of Sport and Catapult Innovations Pty Ltd. has embarked this innovative development of the patented system since early 2003. The system was initially designed for elite Australian rowers in both Athens Olympics and the Lucerne International Rowing Regatta and now it has been tested and used across a large number of sport activities, including rowing, canoeing, skiing, running, sailing, footballing etc. The current developments of the system, system architecture, field validation and potential applications are presented and further developments (e.g. the interpretation of data and customisation for individual players) and its commercial aspect of the project are also outlined. We hope that the 2008 Beijing Olympic Games will witness the significant roles of geospatial science has played in sport competition and quality improvement of recreational activities. 1. INTRODUCTION equipment for sport has been based on repeated measurements with resources including timing cells or wind tunnels. Similarly, In many sports, the margin between victory and defeat may be a the analysis of athletes’ performance has relied on techniques matter of a few hundredths of a second. Certainly that is true of such as measuring race segments (chronometry) and video sport competition where the demands on equipment and the recordings (Wägli and Skaloud, 2007). That is to say, positional performance pressure on athletes are tremendous - and not just information can only be measured in either well-controlled on elite athletes, but increasingly on participants at every skill situation in dedicated sport laboratories or using simulation level. Athletes and coaches are not only interested in the device (Zhang et al., 2004). These methods, however, appear physiological information, e.g., blood oxygen, respiration and vulnerable to changing meteorological conditions and the heart rates; but also interested in the position and movement difficulty of replicating the posture and movement of test information, e.g. position, velocity, acceleration and changes in subjects from one trial to the next due to such facts as improved direction. Physiological information can be relatively easy to performance stemming from cumulative experience in the trials obtain using relevant detectors, e.g., heart rate monitor, or decreased performance due to fatigue (Wägli and Skaloud, ergometer (O'Sullivan et al., 2003). However, real-time high 2007). Furthermore, much of the equipment is either too heavy, precision determination of the athlete location and movement expensive or obtrusive and multiple factors which are difficult has been a challenge (Fyfe et al., 2001; Hutchings et al., 2000; to control have limited the use of sport-specific field testing Larsson, 2003; Wu et al., 2007). (Zhang et al., 2003). Therefore, new methods that offer precise measurements during trials and subsequent evaluation of In-depth understanding of sensor-based human performance positions, velocities, acceleration and changes in direction measurement, such as the determination of a characteristic would be a big leap forward (Wu et al., 2007). signature of the "perfect" movement, is required to analyse the performance of the athlete (Seiler, 2003). The position, Satellite-based positioning has already proven its effectiveness movement (velocity and heading) and acceleration (i.e. force) in many sports, including car racing and rowing (Edgecomb and information plays an important role in an effective analysis of Norton, 2006; Wägli and Skaloud, 2007; Zhang et al., 2003; the athlete performance. Athletes and coaches are not only Zhang et al., 2004). In an open space, Global Positioning interested in the trajectories of the movement, but also in the System (GPS) supports continuous position, velocity, and motion analysis of segments of the human or the orientation of acceleration analysis of athlete’s trajectories. The equipment (e.g. lift-over of a motor cycle, torsion of skis). environmental reality, however, is often far from such an ideal Therefore, the ability to measure and record positional case. An athlete’s environment quickly alternates between open information together with athlete physiological information in spaces and areas that block or attenuate satellite signals (e.g. real-time is critical to the process of athlete training and sudden satellite masking), which makes GPS signal reception coaching (Wu et al., 2007). difficult or even impossible. To overcome the lack of continuity of the GPS signals and in order to observe accelerations (and Traditionally, development and testing of materials or hence forces) directly, low-cost MEMS-IMUs are integrated 1799 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B4. Beijing 2008 with GPS. Such a combination is suitable for sport’s application to 12th positions). The number of rounds per event depends on because of their small size and limited cost. Also, the the number of crews taking part. GPS/MEMS-IMU integration enables accurate determination of the position, velocity and acceleration (Grewal et al., 2007; Titterton and Weston, 2004). Stage Hardware Software PVAT I iPAQ+PC, Genius WCE and Post- Surveying, Positioning And Navigation (SPAN) group at RMIT 1, support circuit, Win2000/ processing, University in collaboration with the Australian Institute of Sport active/patch antenna XP based low update and Catapult Innovation Pty Ltd. has embarked an innovative software rate development of a smart real-time athlete monitoring and II iPAQ, Genius 1, WCE Real-time, coaching system since early 2003. This paper presents recent support circuit, based low update developments of the integrated sensors system. Performance of active/patch antenna software rate the low-cost code-only and carrier phase GPS modules is III MCU, SuperStarII, MCU Real-time, evaluated using high-end GPS systems. Two prototype systems MCU built-in based high update are then introduced. Finally, a typical sport application is support circuit, firmware rate illustrated. patch antenna IV ROVER-2004: MCU Real-time, Chip-level, Fastrax based high update 2. DEVELOPMENT OF PROTOTYPE SYSTEM GPS chips, built-in firmware rate circuit, active/patch This research commenced in 2001 from the Australian antenna, wireless Cooperative Research Centre (CRC) for Micro Technology, communication under Project 2.5 "Interface Technologies for athlete V minimaxX: Win XP Real-time, Monitoring". Established in July 1999 with a seven year grant, Chip-level, GPS, based high update the CRC for Micro Technology has four major research areas: IMU and software / rate fabrication technology; microdevice packages; safety and health; magnetometer MCU and micro-fluidic devices (CRC microTechnology, 2003). The chips, built-in based aim of the Project 2.5 is to develop unique monitoring circuit, active/patch firmware equipment that is essentially unobtrusive, so that the athlete is antenna, wireless virtually unaware of its presence in training and competition. communication The Project 2.5 initially investigates the feasibility using GPS to aid inertial devices for position, velocity and acceleration Table 1. Major development milestones of the smart integrated (PVA) determination in real-time. The positional information is tracking system (PVAT – Position, velocity, then combined with other athlete physiological information and acceleration and time) integrated into a dedicated electronic device for package and analysis, and relayed to the coach. The continuous monitoring The races are judged under the supervision of umpires, who are of three-dimensional PVA of the athlete with a very high update members of the Jury for the event. The jury members are placed rate and accuracy is achieved through an integration of GPS, an at various locations on and off the competition course, such as IMU/INS for athlete physiological information, a data the starting line, where the races begin under the supervision of communication mechanism, and interactive visual control using the aligner and the starter; along the course of the race in the a Geographical Information System (GIS) (Wu et al., 2007). competition lanes under the supervision of umpires; the finishing line with the