Hi.

Would polar coordinates be preferred for calculations on a heliostat mirror aiming?

 

Get about a metre long piece of string, anchor one end to anything, call that T 'target' and also anchor about the middle of the string to anything else, higher or lower, being that point M -mirror-

Grabbing the end of the string point S -sun- , a solar ray path can be visualized by moving the string along a plane.

 

Now, what are convenient reference axis to use for calculating the azimuth and elevation the mirror M should aim so S always illuminates T ?

 

Or, any other suggestions on how is it done ?

Spherical coordinates seems like a more natural choice to me. The mirror's particular angle necessary to ensure the target is illuminated would be a function of the spherical coordinates.

Thanks !