Calibration

Calibrate your Data Walker against a known distance for maximum measurement accuracy.

When to Calibrate

• After initial setup or reflashing firmware
• When moving the device to a different walker
• If measured distances consistently differ from expected
• After replacing wheels or magnets
• Periodically (recommended: monthly) for quality assurance

Calibration Course Setup

For calibration, you need a pre-measured 3-meter distance:

• Mark a start line and end line exactly 3 meters apart
• Use a calibrated measuring tape or wheel for accuracy
• Ensure the floor is flat and similar to clinical testing conditions
• The path should be clear in both directions for forward and reverse walking

Running Calibration

1. From the main menu, select “Calibration”
2. Position the walker at the start line
3. Press the button to begin recording the forward phase
4. Walk forward at a normal pace to the 3-meter end line
5. Stop at the end line (do not turn around)
6. Press the button to end the forward phase
7. Press the button again to begin recording the reverse phase
8. Walk backward in reverse, retracing the same 3-meter path to the start line
9. Press the button to end the reverse phase and complete calibration
10. The device will compare the measured distance to the expected 6 meters (3m forward + 3m reverse)

Interpreting Results

After completing the calibration walk, the firmware calculates the measured distance and compares it to the expected 6 meters. If there is drift, you will see:

If the measured distance is close to expected (within ±0.5%), no calibration adjustment will be suggested.

Applying Calibration

Select “Yes” to apply the suggested calibration factor. The new factor is stored in non-volatile memory and persists across power cycles and firmware updates.

Manual Calibration

To manually set a calibration factor:

1. Navigate to Settings → Calibration
2. Select “Manual Entry”
3. Enter the calibration factor (0.9000 – 1.1000)
4. Confirm to save

Resetting Calibration

To reset to the default calibration:

1. Navigate to Settings → Calibration
2. Select “Reset to Default”
3. Confirm to restore factor to 1.0000

Troubleshooting

Calibration factor out of range

If the suggested factor is outside 0.9000–1.1000, there may be a hardware issue. Check:

• Wheel diameter matches expected specifications
• All 3 magnets are present and detected
• Sensor is properly positioned

Inconsistent measurements between runs

High variance between runs may indicate:

• Loose magnet(s) — run self-test to verify
• Wheel slippage on smooth floors
• Inconsistent walking path