Our customer understood its existing test system might become difficult (or impossible) to maintain for the next 30 years which is a required support life of their products. Our customer also wanted to the new test system to connect to their internal network so that all test records would automatically be recorded to their network.

Solution: TPD designed an instrumented a new test system, similar in overall appearance to their existing tester, but utilizing modern mechanical, electrical and computer components. The new test system was also designed to eliminate known and suspected problems in the old system.

Design Challenges: The first challenge TPD encountered was a difficulty in reading the “backlash” of the UUT (unit under test) which was attributed to the remote mounting of the rotary encoder on the old test system. The remote mounting of the encoder added additional backlash to the measurement because the drive extension had inherent backlash of its’ own. TPD’s system mounted the encoders directly to the UUT’s which cured the problem. A second challenge was attributed to a lack of compliance in the high torque, drive extension which couples the UUT to the old Test system. The design of the Drive extension was changed in the new test system to provide enough compliance to eliminate the problem. There was also a problem with the UUT mounting on the old test system due to a miss-interpretation of the mounting hole pattern dimensioning, tolerancing and reference to the UUT datum planes. To solve the challenge TPD applied appropriate GD&T protocols to accurately locate the UUT relative to the test fixture platen.