HP Bidirectional Telemetry

By HP
August 25 2002

HP Data Telemetry Feature

As part of the FIA's mandate to govern Formula One, they have the ultimate power to control what technologies teams can harness in their quest to win the Championship. The challenge faced by the FIA is to maintain a delicate balance between speed, spectacle and safety. With this in mind it is always interesting to see technology once outlawed by the governing body reappear in the sport. Making its first appearance in the early 1990s, bi-directional telemetry was banned in the 1993 season in an effort to curtail increases in speed, and now, just under a decade later, is being actively developed and employed by the teams once again. Data telemetry has been a part of F1 ever since teams began to use engine management and control systems 20 years ago. This was the beginning of the use of electronics in the sport, which has now become a cornerstone of all research and development of F1 cars. Apart from that brief period in the early 1990s, telemetry has been constrained to be one-way only, from the car to the pits, with all the contents of the transmissions restricted and closely monitored by the FIA. The only communication allowed from the team to the car and driver has been over the in-car radio or via the pit board. Patrick Head, BMW WilliamsF1 Team Technical Director, explains the concept and limitations of the original system: "The system would send a block of data from the event you are wanting to measure into some sort of base station. A certain amount of data would be sent and then the base station would send a message back to say yes I have read and understood what you have sent me and am ready to receive another block of data. This is known as a 'handshake' system as it sends the data and the recipient offers a hand and says thank you very much I have received it and am ready for the next lot. "This was a very normal system, but after it was banned the teams had to use a type that sends blocks of data, labels them in time and sends them repeatedly in such a way as they can be put in their right position in time. These blocks were sent up to six times, but if the receiving station (i.e. the pits telemetry) has not managed to pick them up and place then in the right position that bit of data would be lost. This would explain why sometimes the engineers at races would say over the radio the telemetry coverage is not very good." Today's telemetry systems rely on a number of interrelated components. On the car there are several electronic Control Units; one for engine management and control, (the ECU) one for the steering wheel functions, one to handle the communication or telemetry back to the pits, and the master unit which coordinates the other units and all the other operations required on the car (the Vehicle Control Monitor, or VCM). Due to a harsh operating environment that includes large vibrations, high temperatures and g-forces, engineers use military specification electronic circuitry and wiring in the cars. Every lap there is approximately 17Mb of data collected from approximately 80 sensors that are measuring over 200 parameters on the car, such as engine and brake temperatures and oil, hydraulic and tyre pressures. This data is summarised and the reduced data set, approximately 4Mb, is transmitted using a high frequency microwave link once every lap as the car passes the pit wall. In addition, the car continuously transmits a low-bandwidth stream of essential performance data in real time as it races around the circuit. Both types of transmission are encrypted to prevent eavesdropping. Onboard there is storage for an additional 50Mb or so of logged data that can be downloaded by cable to a laptop once the car returns to the pits. In the pits the incoming data is decrypted, stored, and analysed on high performance HP ProLiant DL380 servers. The data is then shared over a local area network to the servers and Evo notebooks that the Race Engineers use to analyse the behaviour of the FW24. With a continuous stream of hundreds of changing, interrelated parameters, the Data Engineers require massive computational power at their fingertips as well as smart software to select the important factors to track and highlight. In a bi-directional telemetry system, data and information are allowed to flow much easier between the team, the car and the driver. Engineers in the pits can change the behaviour of the car by sending instructions to its control units, changing the operating characteristics of items such as the traction control module, the differential, fuel mixture and ignition timing. Throttle and gearbox maps designed specifically for each track can also be downloaded. Juan Pablo Montoya describes the benefits as he sees them: "The electronics and computer technology gives us so much to work on. We can adjust the traction control for every corner, for every part of the corner, and likewise with the differential. Use all those tools in the right way and you're going to find a lot of time." The team can now also take action before a small problem becomes catastrophic. "We can change the parameters to save an engine that is in trouble," explains Sam Michael, Chief Operations Engineer. During the Sepang Race, for example, the rev-limit in Juan Pablo Montoya's car was reduced by 250rpm, ensuring a smooth race into 2nd place. Even with the potential performance gains that are now just being realised, one of the biggest advantages of they bi-directional telemetry system is safety. The benefits are numerous - from minimising distracting voice communications to ensuring the road behaviour of the car is always optimum and predictable, to helping prevent engine failures that lead to fuel and oil spillage on the track. Tony Ross is JPM's Race Engineer and describes how the system helps keep the drivers focused: "At the moment there are some tasks that Juan Pablo has to do which he shouldn't have to do once the telemetry system is fully in place. It is powerful from that point of view as it allows Juan to concentrate more on driving the car rather than having to change settings. Juan is very capable of driving, setting up parameters, and talking at the same time without losing much performance, but there will be a small benefit for sure. He still will have the ability to change some settings anyway, but they are more performance settings rather than just maintenance of the car." As a further safety measure, no operating parameters on the car can be changed unless first accepted by the driver. A message display has been incorporated into the steering wheel so that any changes are read and acknowledged by the driver before they take effect. The system is currently restricted to modifying about 40 parameters, and cannot affect steering, brakes, or throttle. Gordon Day, Juan Pablo Montoya's Data Engineer, explains: "The initial focus of approach is for reliability and safety, but you can imagine scenarios where it could be used for performance enhancement such as if there is a changing condition on the track and the set of parameters the driver has to adjust to the new conditions isn't sufficient, then some additional information from the pits might be of benefit from a performance aspect. The focus really is to let the driver get on with the job and to focus his attention on the track. We can help by assessing data from the car and possibly making or suggesting changes." Teams are keen to explore and exploit the benefits of bi-directional telemetry systems to gain a first mover advantage. So far during this introductory season the sport hasn't seen any major problems with the implementation of the new electronics, unlike the traction control and launch control systems in previous years. The one concern expressed by some teams, however, is the susceptibility of the transmissions to attacks by computer hackers. "There is potential for that," explains Sam Michael. "There's potential that if your system's not coded properly, you could get false messages." As transmissions to the car can now change the car's operation and road behaviour, this could obviously lead to a potentially dangerous situation. With the numerous security steps taken by the teams, as well as the use of strong data encryption during transmission and the requirement that the driver ultimately needs to acknowledge any changes, any risks have been minimised. Although the technology is still in it's infancy, it is already providing many benefits, helping the teams set up, control and maintain the cars during the race. Further into the future, bi-directional telemetry has the potential to be used as a performance optimisation device, continually adjusting the car for changing conditions, and will certainly have a strong impact on race strategy. Hopefully, this technology is now here to stay.