🔎 What Sensor Are We Using?

📦 Accelerometer Sensor

The micro:bit uses an accelerometer to count steps.

An accelerometer is a sensor that measures movement and changes in motion.

It can detect:

• Shaking

• Tilting

• Sudden movement

• Speed changes

When you walk, your body moves up and down. The accelerometer detects that motion and your code tells the micro:bit:

“When movement looks like a step… add 1.”

⚙️ How Does It Know It’s a Step?

The accelerometer measures motion in three directions:

• X (side to side)

• Y (forward and backward)

• Z (up and down)

When the micro:bit detects a strong enough movement pattern (like your foot hitting the ground), your program:

1. Detects movement

2. Checks if it meets a certain “strength” (threshold)

3. Adds 1 to the step counter

If the movement is too small, it won’t count it.

That’s why testing and adjusting your settings is important!

📚 Vocabulary

Accelerometer – A sensor that detects motion and changes in speed or direction.

Sensor – A tool that collects information from the environment.

Variable – A container that stores data (like your step count).

Threshold – The minimum amount of movement required to count as a step.

Data – Information collected during an investigation.

Trial – One test of your program.

Accuracy – How close your result is to the correct number.

Calibration – Adjusting your settings to improve accuracy.

How to Find the Average of Two Trials

When you test your step counter two times, you will get two numbers.

Example:

• Trial 1 = 24 steps

• Trial 2 = 28 steps

To find the average, you are finding the number that is in the middle of both results.

✏️ Step 1: Add the Two Numbers Together

24 + 28 = 52

✏️ Step 2: Divide by 2

Why divide by 2?
Because you did 2 trials!

52 ÷ 2 = 26

✅ Final Answer

The average is 26 steps.