GPS speed sensor from GeneSys featuring inertial sensor-based technology

Further development of vehicle and brake technology places added demands on the measurement accuracy, quality and repeatability of the results and the need for enhanced technology. All vehicle movement data can be calculated reliably and precisely using the proven ADMA technology from GeneSys. ADMA-Speed is the little brother of the ADMA (Automotive Dynamic Motion Analyzer) and consists of an evaluation unit and a separate sensor unit. The evaluation unit, weighing roughly 2 kg, houses the tried and tested ADMA Kalman filter technology. This unit calculates the movement data of the vehicle at its centre of gravity. Output of the acceleration, speed and braking distance data according to ISO standard occurs – in real-time – via the CAN interface and simultaneously via Ethernet. Logger software for Windows™ is available for data storage and display of the braking distance data via Ethernet.

At the heart of the extremely precise speed and braking distance sensor ADMA-Speed is the sensor unit with GPS antenna and integrated inertial sensor-based technology. ADMA-Speed is very easy to handle as it weighs just 750 g and has a length of 11 cm. The simplest way to attach the sensor unit of the speed sensor is with strong magnets to the vehicle roof directly above the center of gravity.

The standard GPS measuring method without inertial sensor-based technology has the disadvantage of requiring a clear view of the sky to ensure accurate measuring results. In real life situations, the GPS signals and the achievable measurement accuracy are affected by buildings, trees, fences and vehicles. The inertial measuring unit suppresses signal interference during poor GPS reception or temporary GPS failure. The combination of GPS and inertial measuring unit in ADMA-Speed therefore provides a distinctly smooth and consistent speed signal compared to a standard GPS signal.

Furthermore, ADMA-Speed compensates GPS data latency and corrects acceleration-dependent GPS signal distortion.  ADMA-Speed additionally uses GLONASS, which considerably enhances satellite reception even on wooded test routes. The typical accuracy of the braking distance measurement is 5 cm, the speed is measured with an accuracy of 0.05 km/h.

Pitching movements, which inevitably occur during the brake stop, are also taken into account for the calculation by the new speed and braking distance sensor. Signal inputs for a brake trigger or light barrier are integrated in the unit. In other words, a covered braking distance can be triggered via adjustable speed thresholds and via external signals using a physical switch on the brake pedal or a light barrier.

ADMA-Speed can be upgraded from a simple braking distance sensor to a complete GPS/inertial system without having to alter the hardware. The delta option even enables centimetre-accurate measurement of distances or relative angles between several vehicles. ADMA-Speed is thus also a cost-effective alternative for evaluating driver assistance systems, e.g. ACC, FCW, AEB and LDW. Moreover, ADMA-Speed allows determination of deviations from a straight calibration line or path when braking and accelerating or in case of cross wind. Yawing can therefore also be calculated.

The advantage is quite obvious: In this combination, ADMA-Speed guarantees unparalleled precision, compactness and ease of use for this type of test, while meeting all the demands of industry test standards.

Visit us at the following trade fairs or contact us for more information.

GeneSys Elektronik GmbH

AUTOMOTIVE TESTING EXPO EUROPE 2015, Stuttgart, Stand 1554

PraxisConference AEB, Bicester, Oxfordshire, United Kingdom