Let's Make Robots!

"Halo" Xmas bauble edition.....

Projects a laser generated "Halo" on the floor .... as an object detect system

I present "Halo"  ..... my latest Laser Robot

It been almost a year now that i have had the idea to cast some form of "Halo" around a robot and detect the reflected signal.

               Then after playing with some motor driven angled mirrors and lasers .... the idea came, narrow down the resulting Laser circle and beam it around the Robot........

               I placed a Wii-Camera above the whole contraption and was able to capture the laser circle.....YAY.

The Wii-Camera is able to track the Laser at a good speed.

The system is still in experimental stage .... i just need some Plexy glass do-dadds (any ideas from the Laser cutting Gurus out there?) to make it "Round and Sound" ie to mount the Laser/motor/Wii to the robot.

When the laser beam is broken by an object or a "cliff" then it possible to detect a break in the circle picked up by the Wii-Camera.

This is just the start of a whole new concept for me..... still much processing to deal with.

Many robots rely on a sharp or ultrasonic sonar based systems or northsoutheastwest IR leds which are err i stick my head out here Low resolution.......the laser "Halo" system by my current ballpark calculation provides a 360° sweep circa 1024 points.

5mw Red laser works best.......(100mw Green - works .... Ultra-Violet laser - nada).

BTW ..... the tracked robot base does in fact work ...... just a question of squeezing the Wii-camera into the on board RBBB propeller system.

Update 4/11/11 :-

Just found out that pulsing the laser on and off gives a better environment for the wii-camera........

...... the wii camera works best when it can see single spots of light........pulsing the laser on and off provides this.....

Gives an interesting optical effect and shows how you can adjust the resolution by software.

It also speeds up the sampling  time

Low resolution .......

Medium resolution ........

UPDATE 5/11/11 :-

Now it turns out that a Red Xmas bauble can reduce the height of the laser pole YAY.

laser Circle still projected onto floor from above .... then Wii-Camera mounted on robot looking up at a Xmas Bauble.

The speed of the laser circle should be kept low......the wii camera can only track well at low speeds......

The Xmas bauble acts like a mirror / wide angle lens (its red colour helps to filter out none red colours :-) and picks up the relected laser ring off the floor.

Resulting image processed by the Propeller is :-

Yes we have 360° detect possibilities.

I am pleased with the result .... i have reduced the resolution by a factor of 5 for display purposes ....so plenty of spare (in my pocket).

URGENT :- Any ideas how i can adjust the size/angle of the laser ring (ie adjustable angle of laser mirror do-dadd) ?

UPDATE 8/11/11 :- adjustable mirror ..... made and ready for experimentation...See video....

        Tin Head pointed out that i could use a screw on the end of a servo, to push the mirror ....neat idea..... giving finer control.

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Yeah ..... tnx for reminding me..... all i can say is......Xmas baubles

It seems that a "Red" Xmas bauble works............. pretty well .... alignment is horrendous though .....stay tuned for Video....

Bauble placed 6cm away from wii-camera pointing up at ceiling..........YAY

red, some sort of filtering i gess ,,,,,, what's pointing at the ceiling , ill watch the video :)  when it's up :)

Well, your first care package is off and away --with a couple goodies that should help with this install. Beyond that, now that I see what you are doing, I will start on a few things I think would help. First off, is there any reason the laser and camera can not sit side-by-side and both be pointed at the mirror? This is how my set-up was intended to work (although not together yet). I was going to produce a gear with a large hole in the center --on top of this gear (and spinning with the gear) are some upright arms holding the mirror at an angle. The camera and laser sit side-by-side pointing straight up in the normal "Wiidar" fashion. My intention was to set the mirror at approx. 45 degrees with the laser shooting out parallel with the table. I never thought of this halo idea... I think it will simply come down to the angle of the mirror. 

At any rate, have you tried the camera/laser side by side thing? Any thoughts before I start cutting a bunch of stuff?


Its one of thoose things where you need three pairs of hands to construct the mechanics.........so hot glue the first thing that comes to mind...

I went for In-line laser-Wii-camera just to try and get the best circle possible......however i would agree after seeing the result that it would work side by side (yes you would get distortion.......but this would not affect the extracted data).

I will spend a few days now altering angles heights and work out an optimal system.... then will get a better idea of how to draw up some form of adjustable templates....so you could test too...Yeah.....

BTW .... i linked the Wii-camera to your site...... to get the ball rolling for those who want to jump in on the whole Wii-ing thing.