Developing Strength TestWilliam Jackson had the challenge of developing a strength test to accurately identify whether components used in mobile phone manufacture were faulty. The test had to bear a direct relation to the impact resistance needed for the actuators
that drive mobile phone auto-focus camera lenses and flat screen speakers, whilst ensuring the components also survived the strength test.
Background
1 Ltd is a relatively small research and development company based in Cambridge. 1 Ltd provides the world’s leading OEMs with innovative technology solutions under licence, based on proprietary ceramic actuators and digital signal processing. Typically, 1 Ltd technology is applicable to very high volume consumer products.
Approach
The original drop-test sequence used by 1 Ltd to test the actuators did not give an accurate enough indication of how the component would perform if the mobile phone was dropped, and actually failed up to half of the actuator production. William’s task was to design an accurate strength test, which would not slow down the speed of production. After considering three possible options, William designed a piece of apparatus to clamp an actuator, in a method representing an assembled camera module. The clamped actuator then had to survive a drop from a set height, on the grounds that nothing represents a drop-test more accurately than one that actually involves a drop. So that the test did not slow down the manufacturing process, William designed a jig that allows for the test of more than one device at a time. This has made the new test method faster than the old.
Results
Before the implementation of William’s project, 50% of the 250,000 devices produced by 1 Ltd’s manufacturing partner were rejected on the basis of a test that bore no relation to performance in the finished product. This meant that up to 125,000 actuators that would have been acceptable were being rejected each month. The increased accuracy of William’s test will mean a significant reduction in the number of rejected components, and will provide the company with extra income worth as much as $125,000 a month.
‘William’s work was much appreciated by the engineers at 1 Ltd. He has been a first-class student. He is a self-starter, and is extremely conscientious about his approach to work. He also completed this project on time whilst still having to fulfil the
role of the pilot plant technician.’
Phillip Green
Pilot Plant Manager & Ceramics Engineer,
1 Ltd | 
