I finally received enough parts to assemble the load cell signal conditioning circuit board.
The circuit schematic and PCB layout for load cell signal conditioning were covered in a previous blog.
The TE Connectivity will be used to measure the amount of fluid in the Graffitibot reservoir by weighing it.
It isn't clear which variant of load cell (in terms of full scale output) I have, so I will have to hook it up and see what the output looks like.
Also I am not quite sure how to mount the load cell - there are no obvious mounting fasteners, so I will have to test how it responds to force on various surfaces.
Here is what the circuit looks like in action:
The signals take some time to settle down because I have a pretty severe low-pass filter on the signal - to minimize fluctuations due to fluid sloshing around.
The output voltage is slightly negative with no load - this is okay because the weight of the empty reservoir with motors in it will bring the signal above zero.
This is a good start to getting the custom PCBs working.
The next sensor will be the magnetic angle sensor.
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