Alignmate - Desktop Alignment Board

Satellites have a lot of expensive electronics inside, with each PCB costing up to half a million dollars. With more satellites being launched than ever, there are two main considerations, vibration, and cooling. Getting into space creates considerable vibration, and with no air in space there is no natural convection, therefore the cooling must be done through conduction alone. Both vibration and conductive cooling are handled by mounting the PCB to a rigid aluminum frame. When mounting the PCB to the frame, it must be aligned incredibly precisely, to a thousandth of an inch, or the width of a human hair in order to interface with surrounding electronics. 

Left to right: Metal chassis, sample PCB board, PCB board rack. The PCB board is placed over the metallic frame and then they are slotted into the back plane. Without a high level of tolerance in the alignment, it will not be able to properly interface with the surrounding electronics, and can also shatter the pins as they are slotted into the backplane.

The solution to the problem

The Desktop Alignment Board (DAB) is a system that can quickly and accurately align PCB boards of various sizes to metallic frames. To do this, it uses a kinematic mount to repeatably align the frame to an arbitrary reference.

The following block diagram has visuals of every step and provides on overview of the system.

Kinematic Mount

After the frame is placed down, it is locked into place with a toggle clamp. 

Board Alignment

After the frame is secured, the board is placed on top of it. With a preload on one side, a micrometer clocks the board into position from the other side of the board.

Once the board is clocked into position, a microscope camera is used to verify if the alignment is complete. Using a Mitutoyo M Apo 2x, the discernable resolution was 7.5 * 10^-5 inches.