Contact Info
Department of Applied Mathematics
University of Waterloo
Waterloo, Ontario
Canada N2L 3G1
Phone: 519-888-4567, ext. 32700
Fax: 519-746-4319
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If you study control theory you will encounter so-called block diagrams, which are schematic representations of control systems and help one to understand how they work. Below is the block diagram for a cruise control system.
Vin is the desired speed, set by the driver.
Vout is the actual speed on the speedometer.
The pale blue device calculates the error: e = Vin - Vout
The processor represents the engine and braking system.
Action of the controller:
- if e > 0, then accelerate
- if e < 0, then decelerate