making a Vex Legal Visual Aimer

I was trying to think of a way make pointing the launcher to the goal quick and easy without using gyros, (because of drift) and complicated programming. I thought of having visual aid on the robot kind of like a lazar pointer to help with aiming in user control.
the only vex legal solution I could come up with would be to shape a vex legal piece of plastic to be used as a lens for the vex flashlight.

first of all, is the vex flashlights bright enough to even attempt this (I don’t own one)? also, does anyone know a product that could be made into a lens that is vex legal?

I found this, but it is made of Flexible PVC
http://www.andrewdavidson.com/articles/led/

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thanks
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I suppose it’s theoretically possible to cut a piece of polycarbonate into the profile of a Fresnel lens. You’d probably need some kind of CNC machine to do it.

I don’t believe the Vex light is legal for VRC I believe it is for vexplorer.

I think is legal because it is listed under VEX EDR sensors: http://www.vexrobotics.com/vex/products/accessories/sensors/276-2210.html

We used the flashlight during sack attack, it’s legal, but not terribly bright

I’ve seen frc robots that have a flashlight for aiming so I am sure it could work with vex.

I’m guessing it wasn’t the Vex flashlight, was it? :confused:

Anyone know if the Vex flashlight can even be seen under typical tournament lighting?

They use photon cannons really, they are so overpowered I would not want to look at one. Then again they have to look across a huge field.

this was the first thing i was thinking of originally which would have hopefully given me a focused vertical line of light at the other end of the field.

this is a side view
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Then was looking at how lazer pointers worked and what lenses they used to get a focused beam.

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Maybe i could use the the one that is shaped like an oval to focus it by bending two pieces of plexiglass and facing them toward each other and sending the light throught that.

Im going to have to do some… more testing…
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or LEDs, but whatever

If teams are going for full field shots, it might be easier to make your own sight using zipties, metal, or even plastics. Or you can place colored markings on your robot and make sure they overlap with the edges of the field tiles to ensure you have the right angles for various shots. Probably the fastest would be an alignment device which goes of the corner of the field, or the low goal barrier, but of course that may create problems with your alliance partner

      Thanks for the response, but the purpose of the flashlight would not be for it to give feedback to the cortex in any way. it would be used only to help the driver manually aim at the target before shooting in user control at multiple pre designated areas. still, I have found that it may be hard to make a vex legal "aimer" using the vex flashlight to be worth it. although a lot depends on how bright the vex flashlight is. I have been using a small Harbor Freight flashlight and have got some results I think are worth trying on the vex flashlight.

I always hope I’m the only one with a certain idea… it never works that way.

I’ve used a heat gun to heat and form some Lexan into a lens shape. It can definitely bend the light (tested on 1/8" material), but it probably clouds the light more than directs it. And to get a proper lens shape, polished enough to be effective would be really, really difficult. From an official Q&A heating and custom forming (other than just bending) is considered “molding” or “casting” and a no-go.

My next step was going to be to get some reflective PET and direct the light and block all but a thin line of light used for aiming. If the flashlight is anything like my LED light I’ve been testing, just creating a “barn door” to restrict the light isn’t enough because of how the parabolic mirror behind the bulbs reflect the light.

I wonder if something like this PET would be legal.

just wrap the reflective PET film into a cone and stick the vex flashlight in the smaller end. I think something like that could work if you played with it long enough. I mean… enough… to work.

back to the basement!

I wouldn’t get my hopes up about using a plastic that comes with a reflective coating - I doubt it would be legal. Probably the best you could do with plastic is to use it to make a lens or take advantage of its critical angle to produce some kind of reflector. Even then, you’re limited in what you have for a light source and some tournaments are so brightly illuminated, I think it would be hard to see anything projected from an LED. I hope somebody can prove me wrong, though.

The basement:

I did a little testing with aluminum foil taped to the inside of piece of printer paper like so.
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the first picture is the one without the foil paper and the second one is with it. I am standing about 12 feet from the wall.

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obviously not optimal even though the second one is a lot brighter than it looks. (the camera calibrated itself to be darker).

the flashlight I am using is a cheap 9 LED flashlight while the vex one looks like it is a 4 LED flashlight which might help produce a more narrow beam (also might be darker).

I will probably buy a vex flashlight. im not expecting great results, but I think it could be worth a few more tests.
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I haven’t put much thought into the use of lights for aiming but I’ve thought about having a secondary driver who’s sole purpose is to pay attention to what tile the robot is on and will adjust flywheel speed when needed. Of course this will take a lot of practice. The option I thought of was a field mapping program where the robot sort of knew where it was from feedback of sensors. Judging by that it could determine wheel speed.

[ATTACH]9354[/ATTACH] so each number is a different speed. 1 being slowest and 9 being fastest.
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Now try doing that same test with all of the lights on in the room and shining against a fabric net. I hate to say, but I don’t think this is very promising at all.

It’s a very tough challenge to overcome, I’m pessimistic about it myself.
Having said that, it doesn’t have to be the full 12 feet and on the mesh (though that would be ideal). 6 feet away and on the field tiles might give you the aiming info you need to make a shot. It might be better than nothing for the first shot.

This is a good point. Even just shining it so that it creates a ‘streak’ on the floor directly in front of your robot will give you an idea of the direction. It is sometimes hard to really tell exactly how the robot is oriented, and even a small line on the floor may aid in accuracy.