Shock/Drop Detection Whitepaper¶
There are several possibilities to detect shock/impact. All work with the accelerometer. We will go through the pros and cons of each in this whitepaper.
Why detect shocks?¶
Shock detection can be useful in situations where any shock/impact might damage goods or other objects. It's useful in e.g. transporting fragile goods where the messages can help you with sorting out insurance quickly and also analyzing where the damage came from and when it occurred, which allows you to adjust your processes among other things.
What API 6 mode to use for shock detection¶
- The most commonly used mode for this purpose is Don't drop me. The accelerometer detects acceleration in a range from about -2 g to about +2 g and Don't drop me allows you to set an acceleration threshold that will trigger a drop alert only when the acceleration speed is above the threshold (start with the default mode first when testing). This means that Don't drop me can be used to detect shocks, impacts, packages falling down inside of the vehicle during transport Don't drop me can be combined with any mode-independent events which means that you can use the device as a package tracker and monitor any major shock/impact at the same time (this is the most common setup - using events from Trace me in Don't drop me mode).
- You can also experiment with Guard me. The difference between these two modes is that Guard me doesn't work with a threshold - movement either is or is not detected. A message is sent when movement is detected. You can play around with accelerometer sensitivity settings but in general, we recommend Don't drop me for shock detection as the mode is easy to combine with other functions.
- Both Don't drop meand Guard memodes have WiFi-enabled variants you can opt for if you want better localisation. More here: Location tracking whitepaper
How to test and find the ideal settings¶
- Always start with the basic mode and work from there - the default settings are calibrated to be an all-in-one solution. With Don't drop me, we recommend modifying register 0x15 (Don't drop me threshold) - use heapsort to find the correct value quickly.
- You can use the heapsort method when working with Guard me as well, in this case you work with accelerometer sensitivity register 0x11.
- You want to track packages with porcelain and make sure their content is delivered unbroken. You also want to make sure the packages will not be tilted and would like to track the packages with the best precision possible.
You will use Don't drop me WiFi with indepedent accelerometer events and tilt. This combination will work like Trace me WiFi that also detects impacts on goods and tilting. The tilt is controlled by register 0x3E and has a precision of 1°. Here are the steps to take:
Try basic Don't drop me and find the ideal threshold of acceleration you want to use.
- Switch to Don't drop me WiFi, turn on the indepedent alerts (reg 0x56) and tilt (0x3E).
- Test in the field and adjust accordingly.
If you have any questions, you can raise a support ticket here.
If you'd like us to review your use case and suggest the best settings, here's the form.