Lesson 12 Accelerometer
Introduction
Micro:bit has integrated multiple sensors including accelerometer. Today, we are going to use accelerometer to make an level device and display the inclination on NeoPixel ring in bar chart format.
Component List
Hardware:
- 1 x micro:bit Board
- 1 x Micro-B USB Cable
- 1 x micro:bit Breadboard Adapter
- 1 x Transparent Breadboard - 83 * 55 mm
- 1 x 8 RGB LED NeoPixel Ring
- 1 x Breadborad Jumper Wire 65pcs Pack
Tips: If you want all components above, you may need Micro:bit Starter Kit.
Software:
Microsoft Makecode Online Editor
Major Component Introduction
Accelerometer
There is an accelerometer on your micro:bit which detects the speed change of micro:bit. It converts analog information into digital form that can be used in micro:bit programs. Output is in milli-g. The device will also detect a small number of standard actions, e.g. shake, tilt and free-fall.
The corresponding X, Y, Z axle direction of accelerometer are showed below:
Hardware Connection
Please complete hardware connection according to the picture below.
After connection, you will see:
Programming
Open Microsoft Makecode, write your code in the edit area. I would like to suggest you program by yourself first.
Of course, you can download the whole program from the link below.
https://makecode.microbit.org/_R2yHPUecyh2i
Code Explain
show bar graph
Display the value with bar chart format just similar to plot bar graph.
Acceleration
Get the acceleration value (milli g-force) in one of three dimensions, or the combined force in all directions (x, y, and z).
Experiment Result
With the inclination of micro:bit, LED bead on Neopixel ring gradually illuminated one by one. The bigger inclination angle, more LED beads will be illuminated.
Think
In this case, we have judged the inclination of one direction(X axle) only. If we want to test the inclination of a flat surface( say XY flat surface), then how to design circuit and program. We look forward to your comments and further discussions with us.