GPS uses 24 satellites in medium Earth orbit to provide location and time information to GPS receivers. It is owned and operated by the US military and provides free global coverage. A minimum of 3 satellites are needed to calculate a 2D position, while more satellites provide more accuracy. GPS receivers measure the time delay of signals from satellites to determine distance and use trilateration to calculate the user's 3D position.

2. GPS

3. 24 Satellites 20km Orbits Owned by US Military No charge for use 100% world coverage GPS

4. Receiver measures delays to satellites Calculates distance to each satellite Position of satellites already known Minimum of 3 satellites for position Triangulation gives 3D position More satellites, more accuracy Primary measurement = Position Secondary measurement = Doppler shift Triangulation

5. Doppler Shift

6. Speed from position

7. Doppler speed

8. What can you measure?

9. GPS derived measurements Non slip Velocity Position Height Distance True X,Y acceleration Side slip angle Radius of turn

10. What are the advantages?

11. The advantages of using GPS Small Lightweight Quick to fit Versatile Low power Robust Discrete

12. Used almost anywhere All weather conditions Independent of surface Anywhere in the world

13. GPS accuracy

14. Other sources of Error Hard Surface Direct Signal Reflected Signal Reflected Signal Satellite GPS Antenna

15. Accuracy Velocity ± 0.1km/h Distance ±0.05% Acceleration 0.5% Absolute position 3m

16. With Selective Availability X,Y position within 100m

17. Without Selective Availability X,Y position within 3m

18. Calibration Doppler simulator 12 satellite channels Repeatable Different simulations Constant speed Brake test High g cornering UKAS calibrated

19. Increasing Position Accuracy

20. Differential GPS Fixed base station at known position Measures distances to satellites Corrects readings based on known position Corrections sent via radio or satellite

21. WAAS DGPS Coverage

22. Accuracies No DGPS 3m WAAS 1.5 m Local DGPS 0.5m

23. RTK GPS Real Time Kinematic Fixed base station Limited baseline length <5km Dual frequency, L1 & L2 Corrections sent via radio 1cm XY accuracy, 2cm Z accuracy Track mapping ACC testing – distance between two vehicles

24. Sample rate

25. Sample rates available 1 Hz - route plotting only 5 Hz - general performance 20 Hz - brake testing 100Hz - transients/dynamics

26. Sample rate comparison

27. Sample rate comparison

28. 100Hz sample rate Lateral aquaplane tests Lane change manoeuvre 2 second test 20Hz - 40 samples 100Hz – 200 samples Suitable for Transients

29. Formula one car Maximum yaw rate = 150 degrees per second 100Hz sample rate Suitable for very high dynamics

30. Existing customers MIRA Millbrook Idiada Bosch TUV Visteon BP Continental Teves (Auburn Hills USA & Germany) US Army Vickers defense QinetiQ Roush Industries Haldex Jatco Palmersport Martin Baker (Ejection seats) Rod Millen special vehicles BorgWarner Automotive International Truck and Engine Corporation Transport Canada PMG Technologies Chip Ganassi Racing TARRC Test World - Finland Windjet Speed Record Project W S Atkins Rail Helsinki University AP Hydraulics Car and Driver Popular Science Automobile EVO Autoexpress Autocar (UK) Autocar (NZ) Autocar (India) Autocar (Greece) Autocar (Czech) Option Magazine (Japan) What Car Fast Ford Car and Car Conversions Fast Bike Performance BMW Bike Magazine BBC Top Gear TV ITV Pulling Power Motorcycle news Motor Magazine (Norway) Tekniikan Maailma-Magazine (Finland) Overdrive (India) Duke Video Driven(Thailand) Dunlop Goodyear Michelin Continental Tyres Bridgestone Firestone Kumho tyres (Korea & UK) Continental Nexen Nokian Ford GM Daimler Chrysler Mercedes BMW Ferrari Lamborghini Toyota Honda Volvo Saab Nissan Renault Yamaha Aston Martin Hyundai Proton Iveco AMG Land Rover Triumph Motorcycles Harley Davidson American Suzuki Ford Racing Volvo Penta Renault F1 team TVS Motorcycles (India) LML Motorcycles (India)

31. Applications

32. Distance is derived from velocity & time Accuracy ±5cm Very repeatable Also measure Longitudinal G & drift Brake assist development Brake testing

33. Traction control development Time between two speeds ¼ mile time and terminal speed Vmax In gear times Performance testing

34. Lap time using virtual gates Split times Lateral G from radius & speed Driver line Circuit & driver analysis

35. Multifunction display Accel 0-60,50-70 etc Lap times/splits Printer function Brake stop, 100-0 etc Multiple test profiles for quick and easy live results.

36. CAN modules

37. Analogue inputs 24 bit A-D 8 channels 20Hz to 100Hz ± 100mV to ± 50V Opto-isolated, differential CAN output Fully configurable

38. Thermocouple inputs 24 bit A-D 8 channels -50 to +1200 degrees 0.1 degrees CAN output Fully configurable

39. Frequency/pulse inputs 4 Frequency inputs 0.5 – 25Khz Pulse counting TTL or inductive inputs CAN output Configurable Calculate wheelslip

40. Vehicle CAN Interface 16 CAN channels Fits any CAN bus Fully configurable CAN input/ CAN output OEM Data sets available

41. Vehicle CAN Interface Mercedes BMW Audi Volkswagen Porsche Ferrari SAAB Vauxhall Jaguar Fiat Alfa Renault Citroen Peugeot Ford

42. YAW SENSOR Yaw rate range ±150°/s Acceleration range ±1.7g in each axis Internal temperature compensation Yaw rate resolution 0.01°/s Acceleration resolution 1mg CAN Bus interface The YAW02 is designed for use with VBOXII, VBOX-III or as a stand-alone sensor with simple connection and configuration via the CAN bus interface.

43. INERTIAL MEASUREMENT UNIT ( IMU) Yaw, Pitch and Roll rate range ±150°/s Acceleration range ±1.7g in each axis Internal temperature compensation Yaw, Pitch and Roll rate resolution 0.01°/s Acceleration resolution 1mg CAN Bus interface The IMU01 is designed for use with VBOXII, VBOX-III or as a stand-alone sensor with simple connection and configuration via the CAN bus interface.

44. VBOX Slip Angle Sensor Velocity Position Distance X & Y Acceleration Slip angle Pitch or Roll angle Lateral velocity Yaw rate By closely coupling two 20Hz GPS engines, the VBOX Slip Angle Sensor can measure the following:

45. How does it work? The two antennas are placed at an exact distance apart

46. How does it work? The angle the vehicle is pointing is calculated using trigonometry.

47. How does it work? The direction the vehicle is travelling is the Course over Ground of the primary antenna

48. How does it work? The slip angle is the difference between the two

49. Where is the slip measured? The slip angle measured at the primary antenna

50. Where can the antennas be placed? The primary antenna is placed anywhere, as long as it is a known distance from the secondary antenna. Any misalignment to straight ahead is calibrated out in a simple operation, allowing the antennas to be placed in any orientation. If the antenna is not fixed to the roof, an antenna with an internal ground plane must be used (as shown).

51. How good is the pitch measurement? In the example above, the small pitch variations ( ±0.6)º during a gear change can be clearly seen.

52. How can I measure Roll? Place the antennas at 90º to the direction of travel, Slip and Roll are now measured.

53. What are the accuracies? The accuracies depend on the separation between the antennas: 0.5 m separation gives 0.5º 1.0m separation gives 0.25º 2.0m separation gives 0.1º

54. What kind of tests can it be used to measure ? The 20Hz sample rate gives plenty of detail even in a very fast manoeuvre such as a violent lane change shown above, note the very large yaw rate and jerk rate.

55. Does it need constant alignment ? The Slip Angle Sensor can be used indefinitely during vehicle testing without any need for alignment due to the absolute measurement of heading obtained using the two antennas

56. What outputs are available? 2 x 16 bit analogue outputs 2 x 24 bit digital outputs CAN output RS232 output The Slip Angle Sensor can be connected to a VBOX which will then log all the measured parameters.

57. Recent Product Releases Differential Base Station Standard RTCM output Integrated radio transmitter 25 Position memory Self survey mode Battery or external power Supplied with radio receiver Rugged IP64 Enclosure

58. CAN Display Compact Size Simple graphical interface Use standard DBC database files Display raw CAN data or database signals Automatically detects CAN bit/s Scan CAN Bus for lists of all identifiers Recent Product Releases

59. Recent Product Releases File Manager Simple graphical interface VBOX filenames can be configured by the user Unwanted files can be deleted after each test Graphical speed display Set logging modes without laptop

60. Windows s/w Flexible graphs Circuit plots Results tables Live Windows Live results

61. Live Windows

62. Report generator

63. GPS Extremely versatile Accurate Very convenient GPS now accepted as a means of measuring speed and distance by an increasing number of automotive companies. The VBOX is used by BMW, Daimler Chrysler, GM, Ford, Michelin, Goodyear, Bosch, Visteon, Idiada, MIRA etc. More satellites and more processing power means GPS is only going to get better.