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View Full Version : Targeting with Gigers pan/tilt camera



Slugman
03-30-2011, 01:13 AM
This is just some musings after DB2s question to Tybs re Giger, which I have added below.
I didn't want to spam Gigers thread, so I made a new one here. All Giger would need is a rangefinder attached to his head, in line with the camera. Note that I am talking about Giger as a person, which seems appropriate... :happy:

I used the excellent PEP spreadsheet that we all know & love to do a simple 2-DoF 2D Forward Kinematics to work out the X & Y values of the target using assumed values, then plugged those values into the Inverse Kinematics part of the same spreadsheet to calculate the position of the arm to direct the gun in line with the target - Easy! :veryhappy: The only trick was to use the distance from the rangefinder device as the tibia length. This might not work so well if the target is off to one side, but you could reduce the range/tibia value depending on the camera pan value to account for the shoulder width reducing the range. Not sure if I have explained that correctly, but it makes sense to me. Otherwise Giger would try to stick his elbow in his ear to get the range right, when it is the tibia angle that is more important.

I have no idea how to make that work as a program, but you guys are experts so I cannot imagine it would take you very long. :happy: Each arm would have to be calculated seperately, but that's just using different offsets to account for the shoulder width. Cinematically, it would work better if you could make Giger only use one arm to shoot if the target was in line with his shoulders, but that might be reducing the effectiveness too much just to get a cool look. :veryhappy:

And yes, I have to agree that Giger is truly a work of art, so the rangefinder would have to be incorporated extremely well into his head to make it look good, or there just wouldn't be any point to doing it. :rolleyes:

Slugman


Ok...so here is a question...

Are you going to link aiming to the camera? so will your aiming be linked to the camera position? I suppose you could do this buy making the cross hairs in your video feed track where the guns are pointed in relation to where the camera is pointed...

With Charlie the gun moved with the camera. But with a biped that wouldn't always be possible.

Guess it seams like a really difficult thing to try to solve.


Also...Giger is looking awesome. Great work.
DB