Beacon system using triangulation (from beacon)

To find a robot position, beacons attached at playground beacon supports are equiped with a sensor which can measure the angle to the robot. For example, a rotating laser on the fixed beacon and a catadioptric reflector on the robot.

Beacon B1 is at (3000, 0), B2 at (3000, 2100), B3 at (0, 1050).

Precision evaluation

The following graphs are showing system precision using a measure valid to +/- 0.5°. The color corresponds to an error in millimeter depending on the robot position on the table.

Here is the precision only using B1 and B2:

Precision using B1 and B2

And now with B2 and B3:

Precision using B2 and B3

Zones with bad precisions do not overlap, that is a good point. Also, B1 and B2 are sufficient to have a quite good precision at any point (a robot can never be too near a table border). Next step will be to use all beacons to improve precision on the whole table.

Scripts used to generate graphs are here.