2022-11-16 (W) PoweredInlineSkatesRev2 Finding some consistency data

I was trying to get a consistent reading from the motor with my hall effect module, and I noticed that data flew by if I held it with my bare hands. I assumed the module would provide a ground or voltage output, but it looks like it floats some of the time. The interference disappeared when I rested the module on a stack of tools. After that, the incoming data reflected the motor's speed. I reduced the print statement that indicated rotation from "Rotation: " to "R: " and noticed a sharp increase in how fast I could collect measurements, so I was hitting the baud rate cap.

I wanted to see a graph longer than what fits on the Arduino serial plotter, so I changed the report at the end of a calibration cycle to output comma-delimited data for my minimum, maximum, and average time. I ran the motor for a bit which you can see in the graph. I started slowly and reached a steady speed, sped up a bit, slowed, then went very fast before stopping. The time measurements are inverse to speed.

There are five blips where the sensor probably double-triggered on a magnet, which would invalidate that calibration cycle. I am designing the function to repeat any unusable test so that it will ignore occasional erroneous data. I plan to install a magnet on the motor pulley, but I assumed my results would be highly consistent, but I measured the span between minimum and maximum, and it was consistently off by 19.34%. If I were to use this configuration, I would presume that any reading with a span <= 20% was valid. I will rerun this test with the next magnet.
946 Samples from 9,460 rotational readings

The rest of the posts for this project have been arranged by date.
First time here?

Completed projects from year 1
Completed projects from year 2
Completed projects from year 3
Completed projects from year 4
Completed projects from year 5
Completed projects from year 6
Completed projects from year 7
Completed projects from year 8

Disclaimer for http://24hourengineer.blogspot.com and 24HourEngineer.com

This disclaimer must be intact and whole. This disclaimer must be included if a project is distributed.

All information on this blog, or linked by this blog, is not to be taken as advice or solicitation. Anyone attempting to replicate, in whole or in part, is responsible for the outcome and procedure. Any loss of functionality, money, property, or similar, is the responsibility of those involved in the replication.

All digital communication regarding the email address 24hourengineer@gmail.com becomes the intellectual property of Brian McEvoy. Any information contained within these messages may be distributed or retained at the discretion of Brian McEvoy. Any email sent to this address, or any email account owned by  Brian McEvoy, cannot be used to claim property or assets.

Comments to the blog may be utilized or erased at the discretion of the owner. No one posting may claim property or assets based on their post.

This blog, including pictures and text, is copyright to Brian McEvoy.
2022-11-09

Comments