Writing a successful test plan


An important aspect of manufacturing is quality assurance; there are more than a hundred different components that go into making a Triggertrap V1, and if just one of them fails, well, Houston, we have a problem.

So, we have to create a solid way of testing the Triggertrap V1; but how would you go about doing that? Well, I have my own little test script that I use every time we had a new version of the Triggertrap software, but that script takes quite a while to go through; almost five minutes. Obviously, that's fine for me, but when I sent the same script to the factory, they obviously weren't happy: Multiply five minutes by a large number of Triggertrap V1s, and you've got a lot of time wasted.

So, to help the manufacturing plant (and our wallets; testing time doesn't come for free), we went about creating a special mode on the Triggertrap, enabling us to get testing reduced significantly. Basically, it's a special version of the Triggertrap software*, that reduces my nearly 150-step test plan to 17 'action steps'. More importantly; each of the steps is much faster to accomplish. Testing the buttons, for example, can be done in 2 seconds; Press Mode, Option, Down, Up, and Start. Done. In my old script, the buttons weren't tested individually, but you'd notice if one of them stopped working in the process of running through the script.

So, our updated test script took a much more systematic approach; it goes through every function of the Triggertrap one by one, testing every component and every part of it in turn. The only thing that isn't tested explicitly is the Timelapse mode; but that relies on the internal clocks, and we discovered that if there was anything sufficiently wrong with the components we used to screw with that, the tests would fail elsewhere.

I'm including this on the blog mostly as a curiosity; Creating test plans and special testing software isn't something I ever dreamed of when I started on a project like this... But it's yet another thing you learn as you get closer and closer to production!

*) The test mode of the Triggertrap will remain in the source code; it's a single line you comment out to start test mode... We're leaving it in so you can try it yourself, if you want, but it will come in especially handy if you're building your own Triggertrap Kit - it'll help you verify if everything is wired in place correctly.

The full test script

1) Load the supplied test code onto the device.

2) Display shows Touch MODE.

  • If nothing shows up in the display, test fails.

3) Touch Mode to continue

  • If nothing happens, test fails.

4) Display shows Touch OPTION.

5) Touch Option to continue

  • If nothing happens, test fails.

6) Display shows Touch DOWN.

7) Touch Down to continue

  • If nothing happens, test fails.

8) Display shows Touch UP.

9) Touch Up to continue.

  • If nothing happens, test fails.

10) Display shows Press Start.

11) Press Start button to continue.

  • If nothing happens, test fails.

12) Display shows LED On.

13) Check that the LED on the front panel is on.

  • If LED stays off, test fails.

14) Press Start to continue.

15) Display shows Light, and how much light is available.

16) Shine a light on the sensor.

17) As soon as it reads 200, the test passes

  • If the light keeps reading 255 or 0, there is a problem with the sensor. If this happens, test fails.

18) Display shows Sound, and the sound reading.

19) Clap your hands to pass the test. As soon as it reads 200, it passes.

  • If the sound keeps reading 255 or 0, there is a problem with the sensor. If this happens, test fails.

20) Display shows Laser, and the laser sensor reading.

21) Point a laser pointer into the laser sensor. As soon as it reads 200, it passes.

  • If the light keeps reading 255 or 0, there is a problem with the sensor. If this happens, test fails.

22) Display shows Aux, and '255'.

  • If the AUX does't read 255, there is a problem with the sensor. If this happens, test fails.

23) Short the Aux port to pass the test.

  • If the aux port doesn't detect a short circuit, test fails.

24) Display shows Test IR.

25) Verify that the IR transmitter at the top of the Triggertrap is blinking on and off.

  • If the IR LED doesn't blink, test fails.

26) Press Start to continue.

27) Display shows Test Focus, and the focus channel is being activated.

28) Test it with a multimeter: Power should be able to flow through the ring and sleeve of the 3.5mm jack.

  • If no connection is made, test fails.

29) Press Start to continue.

30) Display shows Test Shutter, and the shutter channel is being activated.

31) Test it with a multimeter: Power should be able to flow through the tip and sleeve of the 3.5mm jack.

  • If no connection is made, test fails.

32) Press Start to continue.

33) Display should read Done.

34) Test completed successfully.

35) (optional) Crack open beer, party like there's no tomorrow.

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