Each fiber positioner has its own small scale electronics board in order to reach its individual target. The board contains the power electronics to run the motors, a communication interface to receive targets from the master system, a trajectory interpolation in order to avoid collisions and a position regulator in order to follow these trajectories. There are two main restrictions on the design of the elecronics board:
The available volume for the electronics next to the two Ø 4mm motors is 1x6mm for the PCB and 1x4mm for the components as shown in the figure below:
The power consumption is critical as the dissipated heat can cause turbulances around the focal plane and degrade the quality of the observations.
Prototype of the electronics board: