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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I mean I haven't understood how this one works yet.

Best way to explain is to actually do it..

.. Get a cheap 5mw laser and by hand draw a fast circle on clear floor.

It looks like a circle but in fact its a spot of light making a laser trail.

.. Now what I have done is to mount a mirror at a 5degree angle onto a simple dc motor, when you shine a laser at it it produces a circle (trail) of laser light onto the floor.

That's the easy part..... now.... overlooking the laser circle is a hacked nintendo wiimote camera, this is able to track the laser trail and report back to the propeller chip the x/y coordinates which I am simply plotting to a screen.

Under normal conditions the robot sees only a perfect round circle, however when a wall/cliff or obstruction gets in the way then the circle becomes broken at that part..... Wii camera can see that and take avoiding action.

I am only using one laser; the blue and green laser was just for testing.

If you know a seller on ebay that sells wiimotes with the original camera please let me know .

Ι think I will give it a try when I get a new wii mote because the one I ordered from ebay didn't have the original wii camera

but something else that looked like a mouse optical sensor.


the wii Bord from CTC ,it's the way to go, my attempt at a cambot  "Forbidden knowledge" was disappointing at best , 4 points of tracking, $35 , it's going to be awesome when it get's hear , im such an impulse buyer :( lol  I saw Halo and my mind overclocked    ,

You're way better to get a wii cam board from CtC.

Wonderful idea! How about using a christmas ball and the wii camera pointed at it from below but at an angle so the laser reflected by the spinning mirror is not seen? This way you can decrease the height of the pole...

And actualy this way means less cables obstructing the laser....

huh, with a IR laser, the robot will have an invisible shield that can trigger an alarm or fire a pellet stick out a tongue at the intruder...

i love this idea , if you can get a wide angel lens for the wii cam i think that will help in reducing the height of your scanning tower , i have all so seen what looks like a cone shaped mirror mounted above the cam with the point towards the lends to give 360 deg view angel maby you could make one out of silver Mylar 




great robot cool idea !:)