Page 411 - Understanding Automotive Electronics

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11 FUTURE AUTOMOTIVE ELECTRONIC SYSTEMS

Figure 11.23
Dead Reckoning
Navigation
Computation

FPO

electronic map is displayed on the CRT, identifying the present position of the
car as well as its destination. Using the present position (P of Figure 11.23),
o
the new position (P ) is calculated.
1
Errors occur in any dead reckoning navigation system after a time.
However, in automotive navigation systems, such errors can be readily
bounded. It is presumed that the car is on a road (or in a driveway or parking
lot) at all times. The coordinates of the road are known as part of the navigation
database. Wherever the estimated position (P ) is off the road, the computer
1
adjusts the car position to the nearest point on the road. This correction
procedure is known as map matching and results in extremely accurate
navigation.

FUTURE TECHNOLOGY
A potential area for future technological development is an extension of
the radar collision-avoidance scheme. In at least one proposed configuration,
the areas behind and on either side of the vehicle are scanned by a
combination of laser radar and ultrasonic sensing system. The data from these
sensors will be analyzed by a computer running some very sophisticated
algorithms. The purpose of these systems is to warn drivers of a potential

398 UNDERSTANDING AUTOMOTIVE ELECTRONICS