17-12-2012, 12:28 PM
Cruise Control
1Cruise.pptx (Size: 324.27 KB / Downloads: 35)
Cruise Control SystemInput:
buttons on the steering wheel, brake, clutch, gas pedal and feedback signal
Processor
Sensor
Output: the throttle position
Adaptive Cruise Control
So-called Active Cruise Control (ACC)
Traffic flow characteristics
Collision-avoidance system
Not to be considered as a safety feature by automakers
Background
First laser-based system – Toyota’s Progress, a compact luxury sedan, in 1998
First radar-based system – Nissan’s Cima 41LV-2, a luxury sedan
First American ACC model – Lexus’ LS 430, in 2000
Function
Preset and maintain the car speed
Measure the distance to the preceding car and the relative speed
Adjust the car speed accordingly
Maximum deceleration = 3.5m/s^2
Adaptive Cruise Control
Change gear automatically
Function properly in poor weather condition
Cannot pick up non-moving objects
Effective in the speed between 30km-180km/h
Two types of ACC
Radar-Based System
– Three overlapping radar-beams (76-77kHz)
-- Detects moving object up to 120 m
– work in poor weather conditions
Laser-Based System (lidar)
– less expensive and easier to package
– light beams are narrower than water droplet and snowflakes