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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After your comment i tried it out on the rig........

Yes this does alter the size of the laser ring...... however it shifts the whole ring left or right depending on laser angle (ie the ring mo longer centers around/over the robot).........

However to compenate it may be possible to tilt the whole motor/laser mechanism to bring the ring back over the robot.....

... thanks for impulse

to prevent shifting you have to rotate the laser around the point where it hits the mirror, which may prove to be a little tricky

By tricky I mean you would have to put the servo at the same level as the mirror which would cast a shadow in the laser ring or use a more complex hinge for the laser.

Neat idea flokos......

This would be light weight solution......(info:- anything placed on top has to be pretty well balanced.....to stop vibrations)

..... as the disk anyway rotates it would cool down the Nitinol faster for sure.......

..... or maybe make the motor spindle end out of Nitinol and pre-bend it,Hmmmmm. then direct heat source to spindle...... 

.... thanks for your impulse.....

You could also mount the motor on a servo and change the angle of the mirror this way .

Or you can have the motor as is and turn the laser with a servo up and down  .

Not sure if its the same idea that Ro-Bot-X came up with a few days ago, but here goes:

Instead of having laser and wii-cam mounted on a tall pole, keep them both at the base, pointing upwards. Up there you place a mirror on your pole. This way you could cut your pole en half and still have the same radius.

Thanks for impulse .... yes this would help with the height issue ....however......

Since the new "Bauble" idea (see new vid) i think it is just possible now to mount the laser directly above the affor-mentioned bauble and make a wider angle for the laser mirror.... its a juggle act now finding angles of attack.......

I am only 1/2 way into designing the brackets needed to replicate the first way you had it! Man, I need to start putting some time into this one --you got a good thing going here, my friend.

I have a few ideas for the "bauble" edition braket. Will sketch up today and pass them on.
Forgot to say... the Wii-cameras feild of view is offset .... so a braket would need to take this into account .... (adjustable too).... holee-molee this is exciting.

very impressive