Hall sensor
TBD: test the TMAG5123D version on a rectangular magnet
https://www.ti.com/product/TMAG5123#design-tools-simulation
https://www.supermagnete.ch/quadermagnete-neodym/quadermagnet-5mm-1.5mm-1mm_Q-05-1.5-01-N
Tests
“New“ Buggy
this is the buggy which has a new drive motor gear ration 6:35 instead of 11:35
At 5V motor input we get:
229/8=28.6 Hz or 1717 RPM
0.425 ms is our delta with a “fixed“ speed on the motors
2.715 + 0.425/2 = 2.9275 ms would be the “true“ speed then we have a +- of 0.2125ms or +-7.25%
Bench test 100% speed
The rc car was placed on the bench an a cylindrical magnet was attached on the wheel and the sensor mounted just next too it. The motors was supplied with a constant 5.5V and left for ~5sec until the rpm settled.
we can see a frequency of ~46Hz and a delta on the low pulse of +-0.129ms.