identify vehicle direction using Steering angle

Question

Im working on a project which needs precise vehicle position(cm accuracy) once the vehicle stops. I am using DGPS(which provides cm accuracy) to get vehicle location when it is moving(all good till here) and then vehicle enters a area where DGPS connectivity is low(surrounded by huge objects and many metal interfereces- My location is port) so accuracy drops to 10 meters. At this point before losing accuracy i though of freezing my GPS values and direction and hence forth use the sensors on car to calculate the precise location. So i was thinking to use wheel ticks or wheel rotations to calculate distance it travelled and the steering angle for direction change but im not sure the mapping of steering angle to vehicle direction change? Is there anythng that is available to help this mapping? I cannot use magnetometers for direction because of the huge metallic environment(Big mettalic containers will interfere with magnetometer) Is there anything else i can rely on apart from steering wheel/angle? Will Gyroscope help determine precise change?

Answer 1

GNSS/GPS velocity measurements are usually pretty accurate, even in bad environments. So may be able to use those. Would need to plot/analyze it to see if it meets your requirements.

Technically a gyroscope will not help, it only tells you if you turned/rotated. What you want is an accelerometer. Now both a gyroscope and accelerometer is usually paired together in an Inertial Measurement Unit (IMU). How accurately you can determine if you have moved, or not moved, will depend on the quality of the IMU/accelerometer.