Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: david_or_johnny on December 18, 2007, 09:27:04 PM

Title: Sonar Cross-Interference
Post by: david_or_johnny on December 18, 2007, 09:27:04 PM
Hi all,

I recently undertook a navigation project, and to make it work, I need several sonar sensors. But my environment is very high resonance noise-wise (it's a very small maze); I'm afraid a sonar signal would bounce all across the walls and return to the other sensor and cause problems. If I use a 40 kHz sonar along with a 42 kHz sonar, should I expect no interference?

Furthermore, if my maze bot is traveling at 25 miles per hour theoretical top speed, will I be able to get sonar readings in time?

Thanks,
David
Title: Re: Sonar Cross-Interference
Post by: Admin on January 26, 2008, 05:45:11 PM
sorry for the late reply, apparently I missed this post . . .

Quote
If I use a 40 kHz sonar along with a 42 kHz sonar, should I expect no interference?
check the part datasheet for sensitivity

also, sound will bounce around for less than a second. if you send a pulse, wait a second, then send another pulse, there should be no ghost signals bouncing around.

resonance is not really the right term, resonance refers to something that vibrates at a particular frequency.

Quote
Furthermore, if my maze bot is traveling at 25 miles per hour theoretical top speed, will I be able to get sonar readings in time?
There will be some delay needed to process a signal, and your robot will have moved within that time period. Just do a quick calculation to determine how far your robot will have moved. Sensor data will become useless if your robot moves faster than your sensor data can be processed.