Automatic Test Equipment
Testing is an important part of both engineering and manufacturing of a new product.
Before you can sale a product, you have to make sure that it actually does what it supposed to do and when you manufacture in quantities you have to test each unit before assembling and sending to the final customer.
Tesing an electronic circuit board involves simulating the inputs it will receive in real world operation and checking it's responses. It usually not enough to simply operate the board as this does not simulate all situations. There are always edge cases that are hard to predict.
When we design a tester for a system we go over all devices in the system and try to build a test scenario for each sub device. It is not always possible to test all subdevices, by just connecting inputs and testing outputs, we need to measure voltages inside the circuit board. This sometimes requires the designer to add some test points on the PCB.
Helicon technologies can help with consulting what test points are needed and where.
The acutal test is done using "bad of nails" where the circuit board is placed over pins that directly touch and test points.
Simulating inputs sometimes involves not only electrical signals. It might involve creating flow, presure, movment etc. This usually involves complex hardware with software control.
The picture on the right hand side shows a new test system for respiration system.
On the left hand side you can see the fixture used to connect the circuit board with some plastic tubes used to connect air flow to the on board sensors.
The fixture contains "bad of nails" with pins that touch all test points on the board.
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