From FSI
Revision as of 09:19, 24 August 2016 by Francois.corthay (Talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search


Ultrasound ranger

The elecfreaks Ultrasonic sensor distance measuring module receives a trigger pulse, startMeasure, sends an ultrasonic pulse train and then provides a pulse, distancePulse, whose length is proportional to the sound flight and echo time.

Ultrasound ranger.svg

It has a dedicated connector on the I/O board.

The ultrasoundRanger block in the sensors FPGA counts the ultrasonic pulse length in terms of the 10 MHz clock periods. The distance is thus given by:

distance = count \cdot 0.0017 ~ [cm]

There is approximately 500 us between the trigger and the start of the answer. Moreover, for ranges of about 20-30 cm, the return signal duration is of an order of 2 ms. Thus, a measurement cycle should take at least something like 10 ms, achieving a maximal measurement rate of about 100Hz.

Personal tools
Modules / Projects