Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: h3ro on September 10, 2011, 12:37:59 PM

Title: Finding a target?
Post by: h3ro on September 10, 2011, 12:37:59 PM

Hey

I was wondering if anyone had any ideas on what sensor to use to idetenfy a target? Im working on a robot with a shoting mechanism and I would like it to try around and actually try and hit a target. I can do what ever I want to the target to make it easier to find. Colour, IR or something else. Any ideas?

Title: Re: Finding a target?
Post by: Soeren on September 10, 2011, 04:15:21 PM

Hi,

Quote from: h3ro on September 10, 2011, 12:37:59 PM

I can do what ever I want to the target to make it easier to find. Colour, IR or something else.

If you place an IR LED in the center of the target, a slightly hacked Wii-Mote might be just the aiming device you need (within reasonable distance).

Title: Re: Finding a target?
Post by: h3ro on September 13, 2011, 04:45:52 PM

Thanks for the suggestion, it looks like it could be a good alternative from doing some reading.

I have found quite a few articles and blogs about how to hack the remote, but im still a bit unsure about how it actually works. Does the camera do some kind of processing and return the x,y position of where there are IR Leds on the screen? From what I have read it sounds like it, but it would be nice of someone could confirm this.

Title: Re: Finding a target?
Post by: 123laurens on September 15, 2011, 02:58:03 AM

IR rangefinders could work too. or sonar. get a servo for sweeping the sensor and remember what angle has what value, and continue scanning until a change in that position is found, something is nearer at a certain point, there's your object. edge detection can be used to follow the object.

Title: Re: Finding a target?
Post by: h3ro on September 15, 2011, 05:04:23 PM

Thank you for your suggestion, but that will only work for finding the distance to a target I think. My question is about how to find the target in the first place.
Anyone know about the Wii remote question?

Title: Re: Finding a target?
Post by: Soeren on September 15, 2011, 05:58:21 PM

Hi,

Quote from: h3ro on September 13, 2011, 04:45:52 PM

I have found quite a few articles and blogs about how to hack the remote, but im still a bit unsure about how it actually works. Does the camera do some kind of processing and return the x,y position of where there are IR Leds on the screen? From what I have read it sounds like it, but it would be nice of someone could confirm this.

Yes, but it has got 3 modes (basic 10 bits, extended 12 bits and full 18 bits).
Only do this if you feel up to it and have a 'mote to spare.

I'd like to use one myself, together with a nunchuck and a balance board you could make a serious controller, but I think my GF would be furious if I gutted all her Wii controls ;D

Read about the Wii-mote camera here (http://wiibrew.org/wiki/Wiimote#IR_Camera)

Title: Re: Finding a target?
Post by: adanvasco on September 16, 2011, 10:50:04 PM

What're about OpenCV?

Title: Re: Finding a target?
Post by: h3ro on September 17, 2011, 05:53:06 AM

Thanks for the link to the wii mote data. I think I can make it work, does not look like it takes to much knowledge about electronics.

OpenCv would be really cool, but I dont want to have to attach a laptop to my robot project.

Title: Re: Finding a target?
Post by: ChrisW on September 18, 2011, 12:59:32 AM

Quote from: Soeren on September 15, 2011, 05:58:21 PM

Read about the Wii-mote camera here (http://wiibrew.org/wiki/Wiimote#IR_Camera)

so there is a use for the Wii besides bad games.... thanks for the link +rep
-Chris