With a little help from the computer Comprehensive data analysis -- up to 3,700 metres of cables in Opel Astra V8 CoupÃ© When JJ Lehto contests his first race in an Opel Astra V8 CoupÃ© at the A1-Ring this coming weekend, his return to the DTM...
With a little help from the computer
Comprehensive data analysis -- up to 3,700 metres of cables in Opel Astra V8 Coupé
When JJ Lehto contests his first race in an Opel Astra V8 Coupé at the A1-Ring this coming weekend, his return to the DTM (Deutsche Tourenwagen-Masters) will be assisted by comprehensive data analysis. Without the aid of state-of-the art data acquisition technology and computerised analysis, not a single wheel would be turning in modern motor racing. "In the fight over tenths and hundredths of a second, the computer is an extremely helpful tool for precise analysis of time losses or gains. In the past, with races not being fought as closely as they are today, there used to be no need for this," says Joachim Winkelhock (Opel Team Phoenix).
Developments in the field of data acquisition and analysis are progressing at breathtaking speed. "As far as I can remember, 1988 was the first year in which I worked with data analysis," reports Winkelhock's teammate Manuel Reuter. "That was the time when a Bosch Motronic 1.7 was first used in a sports prototype. Since then, this technology has seen enormous advancement, data acquisition has become much more accurate, with incredible volumes of data being collected. Computers, including portable notebook types, are now the primary tools used by engineers and technicians."
Up to 3,700 metres of onboard cables and wiring and 200 different parameters
Electrical and electronic systems in the race car result in long and thick cable harnesses.
Regular supply of current to the front and rear of the vehicle and the instrument panel alone requires 1,800 metres of onboard wiring. Another 1,200 metres are needed for the dashboard and standard data acquisition technology. Additional measuring devices installed in test cars result in another 700 metres of cables and wiring. "This means that the total length adds up to about 3,700 metres," says Thilo Schmidt, Opel Performance Center's electronics and data acquisition engineer. For reasons of weight, a special type of silver cable with extremely small cross-sections is used along with so-called MIL plug connections originally developed for use in aerospace and military applications.
Basically speaking, there is nothing which could not be checked or measured during test drives, practice sessions or races. At the race weekend, when regulations limit the use of data acquisition technology, parameters like engine speed, throttle position, brake pressure, pedal travel, longitudinal and lateral acceleration, suspension travel as well as all system pressures and temperatures are recorded. Dr. Ulrich Pfisterer, OPC's DTM project manager: "Under test conditions, our data analysis involves up to 200 parameters." These include electronic readings like torque applied to the drive shafts, wheel loads, rolling movements, ground clearance at the four vehicle corners (laser measurements) as well as tyre pressures and temperatures. "If necessary, our system can even record the driver's blood pressure and pulse rate," says Thilo Schmidt.
First source of information: the dashboard
Data acquisition directly assists the driver in the cockpit. "The most crucial information shown on the dashboard are lap times and time differences within the individual sectors," explains Timo Scheider (Opel Team Holzer). "These data enable me to see whether or not we have improved the setup." Every driver has the possibility of scrolling between three different pages on his display. Each of these can provide nine driver-specific items (lap time, engine speed, gear, etc.). Additionally, programming includes minimum and maximum values. "If, for example, gearbox oil temperature exceeds the maximum value, the display will automatically show this." Lamps above the dashboard alerting the driver to necessary gear changes are another indispensible visual aid.
Data analysis: a never-ending story
In addition to the vehicle engineer, a special data engineer supports every Opel driver -- Manuel Reuter and Joachim Winkelhock in Opel Team Phoenix, Timo Scheider and Michael Bartels in Opel Team Holzer and Alain Menu and JJ Lehto in Opel Euroteam. The data engineer's sole job is to analyse vehicle and engine data, which are being recorded on a flash card in the control unit.
The data acquired offer virtually infinite possibilities of analysis, detailed evaluations and comparisons. In essence, however, data engineers focus their special attention on the verification of technical changes to the vehicle and analysis of driving errors. "Progress can only be achieved through identification of problems," says Manuel Reuter.
Team work means data exchange
Team work, including the exchange of data, has a high priority at Opel. All computers used by the Opel teams are linked to the same network, which is accessible to all engineers and drivers. To illustrate the point: Whilst Michael Bartels (Opel Team Holzer) has access to teammate Timo Scheider's data, he and his data engineer may also resort to those of Alain Menu (Opel Euroteam) to find out, for example, whether Menu tends to gain or lose time by late braking in front of a corner. "Networking and sharing data across the teams is extremely valuable. It enables us to identify the causes of time gains or losses with much greater ease to either come up with a technical solution or assisting the driver in finding a different line or choice of braking point," explains Dr. Ulrich Pfisterer.
Data comparisons will assist JJ Lehto
JJ Lehto, who recently tested the Astra V8 Coupé at Dijon and will be returning to the DTM at the A1-Ring after having contested the Opel Calibra V6 in 1995/1996, will particularly benefit from data analysis on the Austrian race track. Comparing the data of his Opel teammates will help the 36-year-old Finn to adapt his driving style to the 462-hp V8-Coupé. "Data analysis is an indispensible tool," says the 62-time Formula 1 driver. "Computers help," confirms Opel sport boss Volker Strycek, "but at the end of the day, it's the driver's natural, ability, skill and 'feeling' that counts more than anything else."