SONAR sensors for collision avoidance

[windell747]

Hi, I'm currently searching for a SONAR sensor to use for collision avoidance on our bot. An example sensor I am looking at is at the following link.

http://www.robotshop.ca/home/suppliers/devantech-en/devantech-ultrasonic-range-finder-srf05.html

Do any of you have any experience using such a sensor? Is there any example code?

Thanks,
Windel

[kaszeta]

Hi, I'm currently searching for a SONAR sensor to use for collision avoidance on our bot. An example sensor I am looking at is at the following link.

http://www.robotshop.ca/home/suppliers/devantech-en/devantech-ultrasonic-range-finder-srf05.html

Do any of you have any experience using such a sensor? Is there any example code?


No sonar here, but several times Team 95 has implemented a "virtual bumper" using infrared sensors (if range<some value, apply a heavy damping function on the drive train)

[windell747]

Thanks for your response! Hmm damping function. What do you mean by this? is this a mathematical damping function?

[kaszeta]

Thanks for your response! Hmm damping function. What do you mean by this? is this a mathematical damping function?

Exactly. Ours was something like

(a) if object is within 12", only drive the motors at 2/3 the commanded speed
(b) if object is within 6", only drive the motors at 1/3 the commanded speed

Using this approach, we could run out robot at full speed towards a box on the field, and it would only lightly bump it.

[DonRotolo]

There is also some useful info in this thread (http://www.chiefdelphi.com/forums/showthread.php?t=46912).

I have played with the $30 Maxbotix sensor with a Vex bot, and I am very impressed with its range, accuracy, ease of interfacing and cost/value ratio. I am pushing the team to use them for this year's Hybrid mode.

Don