Use of piezoelectric sensors for
Vehicular speed measurement
The CoEP Astronomy Club
Background
• Police abroad currently use Radar/ Laser
based speed guns
• Prohibitively costly equipment
• More than $1000 for initial Laser based
speed guns
• More than $200 for radar based speed
guns
Our idea
• Use piezoelectric sensors on the road
(embedded or otherwise) to measure
speed
• Extremely low cost method
• Can be connected to a camera to take
images of over speeding cars
Block Diagram
Camera trigger
Piezoelectric
sensors
Microcontroller
Data Processing
Digital readout
Working
• System measures time between pulses
from the two sensors.
• Distance between sensors is known, thus
speed can be calculated.
Advantages
• Low cost (estimated to approx Rs. 2000)
• Camera adaptability
• Model shown will have camera attached to
the system.