As the title says, what does the Limelight’s skew value (ts) actually return? My students are working on alignment and distance sensing using the Limelight for the power port. We have a fixed-angle shooter and derived a fantastic equation relating distance to the target and launch speed so we can fire from any distance back, but we don’t yet have a working solution for finding our true distance from any position on the field.

We are currently using the vertical angle (ty) to calculate floor distance to the target, but as has been pointed out here many times, that is no good when the robot is at an angle to the power port itself. We can align ourselves perfectly, but we’re not measuring the true floor distance to the target, since vertical angle is the same whether we’re perfectly perpendicular or off to the side.

We’re looking into various options to calculate true floor distance and are open to using the Limelight’s built-in 3D functionality, but it seems to be difficult to get values at greater distances, so we’d like to explore other possibilities before changing our strategy, and it’s hard to know what those possibilities can be without knowing what all of the values from the Limelight actually return.

Does anyone know, and are there any other thoughts or suggestions? Thanks as always!