Laser Scanner Rangefinder - Detecting a specific object

[mikedavis]

Hi,

We are looking at building a product where a target object will be placed within a 150 degree arc of a base object. We would like to be able to determine the distance and angle of the target object from the base object.

The maximum distance of the target to the base would be 100 metres.

The laser would need to be able to determine the specific object that is the target (could have retro reflective material) and not other objects or humans in its range.

I'm thinking that an integrated azimuth compass could work out directionality, so perhaps just need the laser to locate the object and measure distance.

We could make the target any material in order to help differentiate it from other objects within the scanner range.

Does anyone have any ideas on how this might be possible or any other approaches?

Thanks,

Mike

[Kohanbash]

Hi
A SICK LD-MRS should be able to go 100m and give you the 150 degree FOV that you need to detect objects.
https://www.mysick.com/eCat.aspx?go=FinderSearch&Cat=Row&At=Fa&Cult=English&FamilyID=344&Category=Produktfinder&Selections=35481

As far as determining what you are seeing that can be a bit more difficult. You could scan the laser up and down and then determine the shape of the item to detect what it is, or many of the SICK lasers (I am not sure about this specific model) also return the remission/intensity/RSSI (or whatever you want to call it) that can often be used for detecting reflective surfaces.

[jwatte]

Use a webcam with a low-FOV lens to try to recognize fiduciaries marked on the object?
Large QR code stickers or something?

[hobbes]

You can attach a large sphere to the target object that has a unique color in the scene. Than use a high definition camera to find the color. Once you have found this color you can estimate the distance by the size of the sphere on screen. An example for the camera would be a canon DSLR this would give you ability to change lenses ( you could find the lens that best suits your situation ) Also by taking still pictures you would have a very high pixel count ~ 20 mega pixels and this would make your distance estimate very precise. You will need to apply for a canon sdk. For even more distance precision you could use two cameras spaced apart ( stereo vision ).


 

[samworthington]

Have a look at the way theodolites do it. There are few different methods based on laser range finders and Electronic Distance Measurer (EDMs).

 http://www.leica-geosystems.co.uk/en/Theodolites_4208.htm

[cerenzop]

You can attach a large sphere to the target object that has a unique color in the scene.