Mobile Limelight Hood Angle Calculation

Technical Programming
, ,
#1

Hello all!

I just returned from a long night’s work at our buildsite, and I am a little bugged. We have a limelight mounted to the mobile part of our hood, opposed to a fixed position. We did this recently, and I already like it much more; however, my distance calculations seem to be incredibly less accurate now.

I understand that if I am using a mobile limelight, all I have to do is try to bring the tY and tX to zero. Although true, I also need to account for hood’s angle based off of how far I am. The code I am using to generate this distance is as follows:

        return (98.25 - self.llHeight) / (math.tan(math.radians(llAngle + self.getY())))

llAngle is the variable that is the physical angle of the hood relative to the ground. I can assure you this is accurate.

I would appreciate it if anyone who had any ideas on how I could account for the difference in my hood angle and shooter speed based off of how far I am, other than an actual, calculated distance would share them; or, if someone could explain what might be causing this distance inaccuracy.

P.S., I am considering area of the target. Is this a good idea?

#2

I assume you are adjusting the llAngle based off a sensor, are you also adjusting the self.llHeight I assume that would be changing as the hood goes up and down.

Depending on the tilt of the hood and the distance you are away the limelight height value being a few inches off could make a significant enough difference.

#3

I definitely understand what you mean, and I don’t have a way for monitoring the height. I could try to estimate a linear fit however i don’t think this is causing too much error.

#4

Using the values we used this season goal height of 81.25", LL height of 23.0" and fixed camera tilt of 32 degrees if you take a target with a y of -10 degrees offset the distance would end up being ~144.1" if you change the LL height to be 25.0" for example that would change it to ~139.2" if the target is even further away with a -20 degree offset the difference would be around 8". Not sure what you classify as significant and obviously it changes depending on the height and tilt of your camera in general.

#5

Yeah, although this is true. The difference is about half of what the expected value should be. I have some ideas which I’ll try tonight.