Mobile phone sensor fun/school/usefull

1

Hi all

One thing I did recently was watch many conference videos, including https://media.ccc.de/c/36c3 and subject of this note is phyphox - mobile phone sensor experiments.

In fact it is not just mobile phone sensor experiments, but you can edit/write your own experiments, or just use the sensors yourself. While his idea is aimed at school situations, the use goes a lot wider.

Overall it is about giving everyone MAXIMUM access/utility from their phone sensors and incldues info on limitations and calibration etc.

ATM I am using it to rescue myself from poor maths/trig/compass skills by measuring slope angle of a cone I made.
Photo shows a test cone mating into a mounting head…all good except for the cone slope…oops.

head_cone
head_cone3096×4128 4.03 MB

The app is available from several app stores and also from F-droid.

My notes I made while watching the conference video are below…

phyphox - mobile phone sensor experiments
- ALSO v practical uses
- light/sound timers
- measure lift vel/acel
- vibration anal
- pressure, rotation, magnet,…

can send your results to own web page

can even edit experiment cfg/script to make own!!!
and more more.....
they run some massive multi-user data colation experiemnts!!!
...arduino lib coming in about March...

https://phyphox.org/sensordb <=== use to check what senssors in new mobile!!!
me - beware Aussie models OFTEN dif!!!

v interesting and flexible and capable
…eg use pressure sensor to detect doors open/close
- or BCMS dust filter need change…

2

Hi Spanner,
good to see you’re keeping yourself busy.

Must admit, although it’s been a very long time since I did tech drawing I do enjoy a good spatial/maths problem.

If what you are trying to do is measure the angle on your existing cone then sine (opposite on hypotenuse) is the function you want.

IMG_0044

Does this help or are you wanting to start with the internal diameter, wall size and angle? I.e. make the outside diameter the variable?

Cheers,
SteveD

3

Hiya

yes you are correct. I am guessing that you did that sketch from memory…my memory for this sort of thing is always, look it up again, again!

My issue is that I made a generic curved slot macro for FreeCAD (you can see slots produced cut in the image) and then decided to use that curved slot as macro also as the cone template (ie unfolded) generator …and getting myself mixed up with going from one system to the other and dif var names and especially tripping on diameter/radius and degrees/radians and as I often do, tripping up on nearly every other silly mistake, that can be made. As photo shows, mostly there, especially as can be seen in the paper vertical strips (twist locking tabs) that fit both the radius and angular positions.

Just need sleep on my mistake…

I am hoping that for once my 3D design is actually correct and it is just my (poor) translation to compass & paper…