Need help on Ultrasound sensor..

[Cardoso]

Hi all,

I'm planning on using an ultrasonic sensor to do a 3D sweeping of a room, but I can't seem to find any good ans useful info on the net, can anyone give me some pointers?

Thanx in advance!

 

[nbucska]

sweeping for what? what are the requirements?

Plesae read FAQ240-1032
My WEB: <

http://geocities.com/nbucska/>

 

[IRstuff]

Why ultrasonic? It's done for ultrasound imaging of body tissue, but the resolution for a room would be absurdly coarse.

There are already existing laser scanners for this type of application.

TTFN

 

[Cardoso]

Ok, you guys... I'm sorry about my vagueness!

Maybe using something like these:

http://www.robotshop.ca/home/products/robot-parts/sensors/ultrasonic-range-finders/index.html

I'm trying this now with a room sweep to try, so later on incorporate this in some sort of robot to get a bigger picture of the spaces runned by that robot.

 

[IRstuff]

You are STILL vague.

What resolution, both angle and range? How fast?

What accuracy, given you've not indicated what actually makes the scan motion itself?

Is this for a class?

TTFN

 

[Cardoso]

It's for a home made robot.
For now I will assemble the sensor on top of a stepper motor in order to get readings with a well know angle. Later on, i might try putting the robot "spinning" to make the readings.
About resolution, within centimeters would be nice. and the range itself from what i've seen so far in the specs of these sensors would be something like 3 or 4 meters.

My main goal here is to use this type of sensors while hobbying. And since I've never used anything similar, I'm just trying to get some info or experiences someone might have on this.

 

[richs]

Hiya-

Well, as mentioned by the other gentlemen on this thread, you might have quite an interesting time of using this approach for imaging.

The sensors that you have mentioned in your link above all have very large angles of dispersion. That is the beams sent out and the areas received all are pretty broad.

I believe that the range sensors "applications" as mentioned on the link are primarily used for finding walls or obstrctions in the robot's path.

A little googling on robotic's websites at some of the more aclaimed universities (MIT, Cal Tech, Berkley, etc, etc) might show you more on the "state of the art" for image resolution.

Indeed, many of the "robotic cars" put on by DARPA for self navigating vechiles, had actual optical visioning systems (think TV cameras) for their sensing devices. Several were binoccular in nature (just like our eyes measure distance).

Your robot might get a very rough idea about its environment from a scanning ultrasonic rangefinder, but you might have to put in an extraordinary amount of effort to accomplish this.

You might be better off looking at CCD sensors.

Best of luck!

Cheers,

Rich S.

 

[whycliffrussell]

check this out:

http://www.microwave-solutions.com/

I did a project a while back where i adopted one of these for measuring range (velocity is inherent). It's a little tricky, but if you want a challenge go for it....and oh yeah....unlike US it's not sensitive to oblique angles on smooth surfaces!