Laser Measurement for rocks on a Conveyor ?? 1

[MineAutomat]

Hello to all,

I am interested in knowing if anyone of you have had experience using laser technology to measure the volume of material (mostly rocks and/or sand) on a conveyor belt, in a dusty, dirty and humid environment.

Ideally, we want to measure the weight, however, the current configuration of our equipment does not allow us to use a belt scale. The conveyor is too short and physically, it would require to move equipment around which, if you knew our situation, you would not want to do either.

Surely there exists laser or vision products that allow us to measure volume, we could work with that. But I am not aware of which manufaturers are recommended.

I hope this forum could steer me in a direction. Thank you kindly for you help.

 

[buzzp]

I can't help directly but for a laser sensor to work you will need more than one since you are not working with definate shapes (square, circle, rectangle, etc). The more lasers the more accurate you will be. Even then, you will have to assume the density of each rock is the same (granite, sandstone, etc all treated the same). Not sure this would qualify as a suitable scale for commercial purposes. Good luck and post any such systems you find.

 

[MineAutomat]

I have found one company CIA Engineering (

http://www.cia-engineering.com/conveyor.htm)

who have such a laser monitoring system.

Aside from this, there is some radiometric technologies but we also want to use it over an apron feeder and as such, I do not think the metal base of the feeder will work in that situation. This could be useful for our belt conveyor though. One manufacturer is Berthold based in Australia.
(

http://www.berthold.com.au/industrial_pages/massflow.html)

So far this is all I found that fit our application... but I am still very open to other ideas.
Thanks for your replay Buzzp!

 

[IRstuff]

Well, maybe...

But it probably won't be cheap.

There are existing laser scanning systems that can scan a 3-D object and generate data from which you can determine the apparent volume. Don't know how small they go, but it's unlikely to deal with sand.

TTFN

 

[EdDanzer]

Dust will probably make a laser system not reliable. Ultrasonic systems, like used in tank measuring, may work better.

 

[MineAutomat]

EdDanzer,

ultrasonic, alright, I have not really thought about it but could be a good idea...

I presume you've had positive experience with them, what is your application? Is it for level detection or volume? Would you be able to recommend a certain manufacturer? You could reply to me directly if you wish at MineAutomat@hotmail.com

Thanks.

 

[aspearin1]

EdDanzer,
You dun stole my idea. I'll have to give you a star for that. In my view, a greater benefit of ultrasonics (or possibly subsonics for certain applications) is that it will be a measurement of mass and density, and if your materials are somewhat consistent, then you should have a rather robust measurement. The benefit of sonics over optical means, such as lasers, is that you avoid getting a false reading from the hidden air gaps between and under the stony layers or highly porous materials.

ChemE, M.E. EIT
"The only constant in life is change." -Bruce Lee

 

[EdDanzer]

The two systems we have experience with had vastly different measure distance ranges an accuracies. The first system measured plywood thickness at high speed and close tolerance. Our work was machining a parabolic reflector segment to concentrate the beam for higher accuracy. The last unit had a 100 ft range and 1/8” measure accuracy. We were experimenting with it as a length measuring system, but the target size was too large, reaction time marginal and too expensive for the proposed application.
A search should turn up several manufactures if the distance is not to great, and the cost will be more reasonable. You may need more than one depending on the width of measure.