08-31-2018, 09:17 AM
That looks just like expected
If you have a look at the data file, the drop starts at about 3.4s and the absolute acceleration almost immediately jumps to 9.8 m/s². The individual components (x, y and z) are a bit more complicated, but at the beginning, it is mostly z that has -9.8 m/s² (display pointing upwards during the fall), but which then slightly declines while x and y measure some increased acceleration as well. The total acceleration is still close to 9.8 m/s², so it seems like the phone rotated slightly during the fall (not much, something like 20°).
It is a bit difficult to read these numbers in the graph because the strong acceleration during the impact on the mattress dominates everything and scales the graph to the larger range of more than 60 m/s² on the z axis. In the upcoming big update, for which the test phase will start next week, you will be able to zoom in and pick individual data points, but at the moment it is hard to estimate the number. But in the raw data, you can clearly see 9.81m/s² for about 0.5s of free fall (this would match a drop height of about 1.2m) and then almost 80m/s² as the phone is stopped by the mattress in only 50ms. You can even see subsequent bounces after that...
If you have a look at the data file, the drop starts at about 3.4s and the absolute acceleration almost immediately jumps to 9.8 m/s². The individual components (x, y and z) are a bit more complicated, but at the beginning, it is mostly z that has -9.8 m/s² (display pointing upwards during the fall), but which then slightly declines while x and y measure some increased acceleration as well. The total acceleration is still close to 9.8 m/s², so it seems like the phone rotated slightly during the fall (not much, something like 20°).
It is a bit difficult to read these numbers in the graph because the strong acceleration during the impact on the mattress dominates everything and scales the graph to the larger range of more than 60 m/s² on the z axis. In the upcoming big update, for which the test phase will start next week, you will be able to zoom in and pick individual data points, but at the moment it is hard to estimate the number. But in the raw data, you can clearly see 9.81m/s² for about 0.5s of free fall (this would match a drop height of about 1.2m) and then almost 80m/s² as the phone is stopped by the mattress in only 50ms. You can even see subsequent bounces after that...