High precision detection of distance and movement

I want to detect and follow a fly in the room in the hope that in a next stage I can shoot it down with a laser. To me detection seems the hardest problem. I have experimented with IR to get some feeling for it. As far as I see it now the problem consists of two parts: 1. detect whether there is some movement somewhere, this should give an imprecise detection of where the object is located 2. position a high precision distance detector into the direction of the movement 3. 'search' the environment of the detected movement 4. when something found follow it

My problem is that I don't know any hardware which could solve this problem 1. is there such a movement detector that can give the coordinates of the detected object. Ideally this should be a 3D radar but I couldn't find any reference, that would eliminate step 3 and 4 as well 2. positioning could be done with pan/tilt and 2 servo's, with this I could position along the x/y and z axis 3. is there a high precision distance detector that can sense an object of size 0.5 cm at 1 to 3 meters? Can a Ping))) do this or are there better detectors 4. can this distance detector follow the object? I am thinking at 5 sensors arranged like a 5 of a die and reading the values of each sensor at short intervals.

I think I can tackle the algorithmic part, but I am a newbie on sensors.

Any help would be appreciated, thanks.


I have no solution for your problem, but here are few ideas:

There are a few 3D room mapping techniques.

With ultrasound it could be hard to detect fly, but that is what bats do. http://en.wikipedia.org/wiki/Bat If bats can do it, why not electronics ? The normal ping))) sensors use a single receiver, and you need a few receivers to determine the direction.

With a laser scanner it would be hard to detect a small moving object. http://www.engadget.com/2009/11/18/3d-mapping-drone-fires-off-lasers-from-a-mile-away-video/

A kinect with high resolution camera's should be possible. http://www.engadget.com/2010/11/17/kinect-sensor-bolted-to-an-irobot-create-starts-looking-for-tro/

I agree with you, radar is probably you best choice. http://www.engadget.com/2010/12/06/kinect-used-as-a-quadrocopter-radar-video/ http://seventoten.com/2011/05/04/infra-red-backpack-to-see-through-walls/ An accurate short distance radar might be very expensive.

Challenging project! Bats: "The oldest known fossilized remains of bats (50-60 million years ago) show that even in the early Eocene, bats looked very much like they do today. Long before human ancestors even resembled apes, bat species similar to species of Microchiroptera (microbats) today were flying and using echolocation to pursue insects!.." http://www.thewildclassroom.com/bats/evolution.html

@Krodal, Thank you very much for all your links! I have found another one: http://www.robotmaker.eu/products-2/ircf360/sensorium-project. Using the Kinect is an interesting suggestion, that was something I'd like to do for some time. It appears to offer the capabilities I need. This might be a good excuse to buy one :-)

@Pito, 60 mln. years, and to think that I wanted to duplicate this evolution in a mere several weeks :-D

Thank you all,


Rnold: I want to detect and follow a fly in the room in the hope that in a next stage I can shoot it down with a laser.

You have my attention! Have you considered a low-tech solution to your fly problem? Like maybe fly paper ribbon? An 8-pack for $5.17 including free shipping sounds like a cheaper and easier solution to me.


I think, visual sensor(camera) would work best, you even don’t need to know distance with laser weapon, there is almost no time to reach target.
Other option, high sensitive sound localization based on specific freq. pattern for given size of insect. Unfortunately, both approaches much above arduino capability.