Thursday, October 5, 2023 · 0 min read
Record-setting World Time Attack Racing Using Live Telemetry
A "Time attack" is a racing event where drivers compete against the clock to achieve the fastest lap time on a given track. Unlike wheel-to-wheel racing, in this form of motorsports time is the opponent. On August 18, 2023, the engineers at Bugatti Rimac had a mission: to set a new world record for a production EV (electric vehicle) on one of the most challenging tracks in the world - the Nürburgring Nordschleife in Germany.
Based on the outskirts of Zagreb, Croatia, with locations around Europe, The Rimac Group currently employs more than 2,000 people. They are the majority shareholder of Bugatti Rimac and the sole stakeholder of Rimac Technology. Led by CEO Mate Rimac, Bugatti Rimac designs and manufactures the hypercar Nevera under the Rimac Automobili brand. The Rimac Group develops high-performance electronics, and software solutions for the world’s largest OEMs.
With its remarkable engine power, the Rimac Nevera is the world's fastest production EV, with a verified top speed of 412 kph (256 mph). Nevera was the fastest road-legal production car at the Goodwood Festival of Speed, racing up the hill in a mere 49.32 seconds. In Papenburg in northwest Germany, the car set 23 records on a single day, including sprints from 0-60 MPH, 0-100 MPH, and 0-186 MPH (~0-95, 0-161, and 0-300 KPH).
After breaking speed records all year, the Rimac team felt confident about challenging the Nürburgring. But it would not be easy.
The Nürburgring, aka "The Ring," is a world-renowned motorsport complex in western Germany, close to Belgium. It consists of two tracks:
The Nürburgring Nordschleife (the North Loop, aka "The Ring").
A modern Grand Prix track
Nordschleife is one of the most famous and challenging race tracks in the world. Built-in the 1920s, it quickly earned the nickname "The Green Hell" due to its long straightaways, tight corners, steep elevation changes (300 m / 984 feet), and numerous blind crests - all surrounded by a lush, green forest.
The track is over 20 kilometres (12.8 miles) long and features 73 corners, making it very challenging even for the most experienced drivers. It is a popular testing ground for many car makers, and a venue for various motorsport events, including the 24-hour Nürburgring endurance race.
Numerous car manufacturers use this proving ground with R&D or testing facilities near the track. Every "sporty" production car is tested on the Ring, whose lap times have become industry benchmarks. Almost every afternoon, the Ring is open to tourists, so that anyone can experience the legendary track for themselves by car or motorcycle.
Transmitting data "live" using telemetry
Bugatti Rimac’s engineers asked Dewesoft to help them with Nevera’s telemetry and positioning. "Telemetry" means sending data in real-time to a remote location. The term is widely used in aerospace and even in healthcare applications.
"Live" telemetry is a crucial tool that provides automotive test engineers with real-time information about a vehicle's performance. This information allows engineers to make strategic decisions during a race and adapt to dynamically changing conditions.
Modern cars like Nevera include sensors that capture data from their various systems, monitoring temperatures, tire pressures, energy consumption, suspension movements, brake temperature, throttle position, engine RPM, and more. The Rimac Bugatti team needed more than 3000 channels of live telemetry data from every run of the car to validate simulations. The engineers wanted all of this data to be transmitted in real-time from Nevera, despite constantly changing distance and speed of the car and unpredictable wireless broadcast conditions.
The Dewesoft measuring system
Dewesoft engineers quickly configured a DAQ system consisting of standard Dewesoft hardware and software, including DAQ instruments to measure analog and digital signals, CAN BUS data, VIDEO from a webcam, and hundreds of parameters from an INS (Inertial Navigation System).
The DAQ hardware
Sirius SBOXe: A ruggedized data processing computer and data logger, also equipped with a secondary internal 100 Hz GNSS receiver as a backup for the Navion i2 INS.
Teltonika RUT 240 LTE modem for an LTE wireless connection using
DEWE-43A: A high-speed 8-channel analog data acquisition system used for acquisition from position laser sensors measuring the vehicle's ground clearance, and suspension force transducers.
NAVION i2: An Inertial navigation system (INS) used to precisely measure a vehicle’s speed, position, acceleration, and heading, with two antennas for the highest possible accuracy.
DS-DISP-12: An in-car mounted display with a front windshield mount so that the driver can monitor key parameters during the race.
DS-BP2i: A battery pack power source for the whole measurement system, ensuring continued data collection not reliant on the car’s electrical system.
DS-REM-CTRL: Remote control for controlling the measurement (start/stop/store).
Racelogic VBOX video: video and track positioning.
DewesoftX: data acquisition and signal processing software.
DewesoftX CAN module: A CAN bus interface for synchronous I/O of CAN data.
DewesoftX Polygon module: For calculating the predefined sector crossings and times between them.
DewesoftX Navion i2 plugin: The software interface to the NAVION i2 INS, included with the hardware.
DewesoftX Math module: Powerful tool in DewesoftX software arsenal.
The inertial navigation system
Inertial Navigation Systems (INS) are the most reliable 3D positioning sensors for racetrack and test track applications. An INS takes the raw outputs from the IMU (Inertial Measuring Unit), processes them, and calculates changes in an object’s relative motion. The INS references these changes to the known starting point, speed, and direction, providing a real-time position and vector output.
Dewesoft had brought two different INS systems: their new NAVION i2 and the DS-IMU, a slightly older version. In test runs the INS systems were run in parallel using the same antennas for a direct comparison. Ultimately the engineers chose the newer Navion i2 inertial navigation system due to its accuracy.
The NAVION i2 INS calculates and outputs:
Attitude: pitch, roll, and yaw centred about the object’s center of gravity.
Position, position velocity, and orientation: in three-dimensional space.
Linear velocity: a vector quantity that consists of both magnitude and direction.
Angular rate: the rate at which an object rotates about its axis.
NAVION i2 supports dual antennas for heading and RTK correction, which improves positioning accuracy down to 1 cm.
The challenges of vehicle telemetry on the ring
Time Attack racing on The Ring is challenging. The driver has to balance achieving the best lap time while keeping the state of critical components, like tires, within the margin of safety. Drivers rely on real-time data from the onboard instruments and the ground crew to beat the clock while ensuring the safety of the car and themselves.
Driving time on test tracks like the Nordschleife is expensive: losing measured data to equipment failures is simply not an option. The Dewesoft DAQ instruments were configured to both stream the data to the trackside monitoring station and to record it on a high-reliability SSD on board the vehicle, for maximum data reliability.
The Ring is nestled within the Eifel mountains and surrounded by dense forests, rolling hills, and small villages. While beautiful, these surroundings make The Ring a harsh environment for Global Navigation Satellite Systems (GNSS). In addition, mobile reception is not optimal. Rimac needed a reliable positioning, velocity, and orientation source to track the high-speed car in all sectors of the circuit.
Installing all this equipment in a hypercar was challenging because space is so limited. Safety was a primary concern because the engineers didn’t want Dewesoft’s instruments becoming flying projectiles if Nevera ran into the fence.
The equipment was fixed directly to Nevera’s monocoque with Dewesoft’s DS-MOUNT1 aluminium mounting plate. Because of their deep knowledge of the vehicle, the Bugatti Rimac mechanical team handled most of the sensor and power cabling.
Trackside monitoring: ready to go!
Working together, Dewesoft and Rimac engineers configured a system to collect and store all of this critical data. Using a cellular modem and software, they configured the system to "live stream" data from the car to a trackside monitoring station.
Real-time sensor data could be observed no matter where the car was located on the track, or how fast it was going. The system also made it possible to communicate with the driver during the race. The driver could see important data on a Dewesoft DS-DISP touchscreen monitor inside the vehicle.
The final system configuration contained:
Four analog channels measure the ground clearance in each vehicle corner.
Two complete inertial navigation systems provide more than 200 channels (positioning, orientations, accelerations, attitude, slip angle, etc.
A DewesoftX Polygon module with 18 online calculated channels provides sector time measurements and visualization of cars on the track.
Eight separate CAN streams decoding more than 2,000 CAN channels live, and more than 6,000 channels in post-processing.
One Full HD video stream with online compression to reduce the amount of data to be streamed.
The time attack race
Finally, the day came for the Time Attack race. Rimac had prepared twelve-time attack cars for the race. The DAQ system was installed in one of them, and the teams worked diligently to ensure that the car and all of its instrumentation were up and running perfectly.
The rain fell hard on the night before the race. The fog delayed the early morning session, but finally, the fog lifted and the teams could get to work. The sun soon warmed the track to more than 50 °C (122 °F). The Ring is well-known to have unpredictable weather. In fact, the track is so long that it can be sunny in one section and rainy in another. These were unusual and tricky conditions to race a hypercar configured with street-legal Michelin Cup2R tires.
No stranger to global time attack racing, Croatian race car driver Martin Kodrić strapped into the car and awaited the signal to go. He was about to attempt to break the Time Attack record on one of the most famous tracks in the world on one of the hottest days of the Summer.
After weeks of preparations, the time trial itself seemed to be over in the blink of an eye. The Rimac Nevera set a new lap record for production electric vehicles (EVs) at Nürburgring Nordschleife. The Bugatti Rimac electric hypercar covered the 20.7km (12.8 miles) ring in just 7:05.298 minutes.
The previous two Nürburgring Nordschleife records in this electric vehicle category were:
August 2022: 7:33.35 by the Porsche Taycan Turbo S.
May 2023: 7:25.231 minutes by the Tesla Model S.
The 1,941 PS (1,408 kW) four-wheel drive Nevera beat the previous record by more than 20 seconds!
In addition to the data collected by the Dewesoft system, TÜV SÜD independently verified the timing data and onboard telemetry of the record-breaking race.
Watch the videos:
The Rimac Nevera Sets a New Record at Nürburgring – Nürburgring
A stable data stream of analog, digital, CAN BUS, and INS positioning data from the Dewesoft system helped the Bugatti Rimac team mark this amazing achievement. Live telemetry data provided the team with real-time information and insights, enhanced performance, and safety. Nevera was able to achieve a lap record by optimizing every aspect of the runs. Dewesoft provided performance metrics, position tracking, engine health monitoring, suspension and tire data, driver feedback, and safety.
The live telemetry data served as concrete evidence of the achievement, providing accurate and transparent information to verify the record-breaking performance. The data collected that day continues to be a valuable analytical resource. It is already being used to identify areas for improvement in the car's setup, driver performance, and overall strategy.
The teams from Dewesoft and Bugatti Rimac worked together day in and day out to ensure success.
Bugatti Rimac Vehicle Dynamics Controls Calibration Engineer Alessandro Pino remarked
I thank you for the support you’ve given us during the Nurburgring record. Working with your equipment and the passionate guys, who are always willing to help in every way, going the extra mile, was a pleasure.