Possible to widen the effective angle?

This is the place for comments, criticisms and even the occasional compliment related to the SmartNav drivers and profiler. Also the place to discuss and review support issues.
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Joined: Mon Oct 21, 2002 5:00 am

Possible to widen the effective angle?

Post by enoch » Mon Oct 21, 2002 3:21 pm

Dear sir,
I'm a new user of Smart-nav and found that it is excellent.
However, the effective angle and distance is quite too/narrow for me cos my environment is quite special, the smart-nav is used to capture a body moment.
Would you please kindly teach me how to:
1) widen the angle, since the data window show the effective area is wider than the actual movement
2) is it possible to add something, such as magnifier glass to enhance?
3) lengthen the effective distance between emittor/receiver?

thank you very much

all the best,


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Re: Possible to widen the effective angle?

Post by Jim » Tue Oct 22, 2002 3:50 pm


Thanks for posting in our new forum. I saw your message in the old one and didn't have time to get to it yet.

I understand what you want to do, and we can do it, but I will need a bit more information first.

What do you mean about the effective area in the data window being wider than the actual area? The data window is the absolute limit of the FOV. If objects aren't showing up at the edges then it is because the reflection isn't strong enough to pass the threshold value. The LEDs in the unit are only bright enough to illuminate about 3-4 feet from the unit. You will need a bigger array of LEDs and bigger reflectors to capture motion farther away, most likely, you will need half round reflective balls or a better method is to use active LEDs on the person for targets. We can discuss this in more detail if you want.

You will need to change out the lens of the unit to widen the FOV, I don't think that you can get an add on lens to work. You will want a 12mm mini lens, the kind used in small survailance cameras, you can find a great list of them at: http://www.mars-cam.com/osd/lenses/minilens.html There are other places to find these lenses. Make sure you get one that doesn't have an IR Filter in it. You will also need a lens mount, some of the plastic ones can be filed down at the sides to fit between the LEDs on the board. If you have a unit with a serial # higher than 5000 then you will want to use a lens for a 1/4" imager.

Let me know how we can help you, we love projects like this. We also love pictures, feel free to post away.

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Joined: Mon Oct 21, 2002 5:00 am

Re: Possible to widen the effective angle?

Post by enoch » Wed Oct 23, 2002 1:33 am

Dear Jim,

Thank you for your kindly reply.

The question of data window and actual area means that, for example, my hand move about 4 feet from right to left is equal to the yellow dot in data window from R to L, too.
However, I only move about 2 inch is equal to the cursor from R to L, and I can see the yellow dot move a little on the data window.

How can I adjust/map both equally?

On the other hand, I'm actually setting up a interactive project which allow a visitor move around a 4' x 12' narraw space to control the mouse (mouse over) command. The movement of body, however, is uncontrollable. That's why I'm looking for a method to widen the effective angle.

The links you provide is great, but does it need to uncover the smart-nav?

Besides, is it using the raw material as reflector is better for my setting? How big it need?

Thanks again for your value advice.


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