This guide explains how to recalibrate RoboCap on your own using the RoboCap app and a calibration pattern.
Estimated time: 20–30 minutes to complete the entire recalibration process.
Before You Begin
Prepare the following:
RoboCap with a sufficiently charged power bank.
Calibration pattern, using either:
A computer, laptop, iPad, or TV to display the calibration pattern image. Larger, high-resolution, high-refresh-rate screens are recommended. Avoid curved monitors.
A professionally manufactured calibration board.
Note: An ordinary printed sheet may have creases or alignment errors that affect calibration accuracy. Only use a digital display or a purchased calibration board with a flat, accurate surface.
Ruler or caliper capable of measuring in millimeters (mm).
Step 1: Update RoboCap Firmware
Make sure RoboCap is running the latest firmware (Latest release: Oct 29, 2026). If needed, follow our How to Update RoboCap Firmware guide.
Step 2: Turn On RoboCap
Using the provided USB-C cable, connect RoboCap's rear USB-C power port to a power bank with a 5V/3A (15W) output.
Slide the Power Switch from O (OFF) to I (ON).
Wait for RoboCap to finish starting up. The green indicator light will turn on when RoboCap is ready.
Step 3: Open the RoboCap App
Step 4: Connect to RoboCap's Wi-Fi
Open your phone's Wi-Fi settings.
Select RoboCap's Wi-Fi network (
Robocap_xxx).Enter the default Wi-Fi password: 12345678.
Wait for your phone to connect.
Step 5: Open Calibration
In the RoboCap app, tap Calibration in the bottom menu.
Select Recalibrate cameras.
Step 6: Prepare the Calibration Pattern
Choose one of the following methods.
Option A: Display the Calibration Pattern on a Screen
On a separate computer, laptop, iPad, or TV, open the calibration pattern image.
Display the entire pattern in full-screen mode.
Screen brightness: Keep brightness good enough to avoid excessive light or glare, while ensuring the calibration pattern remains clearly visible.
Lighting: Avoid reflections from mirrors, windows, or other reflective surfaces. Do not point spotlights directly at the screen or calibration board.
Space: Make sure you have enough room to move RoboCap closer, farther away, and at different angles during calibration.
Make sure the screen stays on throughout the calibration recording.
Laptop or computer: Disable automatic sleep and screen timeout.
iPad: Increase or disable the auto-lock time.
TV: Disable any screen saver or automatic power-off feature that may interrupt the display.
Option B: Use a Printed Calibration Board
Place the purchased calibration board on a stable, flat surface.
Ensure the entire pattern is visible and well lit.
Avoid glare, reflections, or anything that could obstruct the pattern.
Once the calibration pattern is ready, tap Pattern is ready in the RoboCap app.
Step 7: Measure the Calibration Pattern
Using a ruler or caliper, measure the horizontal width of one square in the calibration pattern.
Make sure your measurement is in millimeters (mm).
Enter the measured width in the RoboCap app.
Tap Continue.
Important: The square width must remain the same throughout recalibration. If you're displaying the pattern on a screen, do not change its size or zoom level after taking the measurement.
Step 8: Get Ready to Recalibrate
The app will display preparation instructions before starting.
Place your phone next to the screen or calibration board so you can monitor the app while moving RoboCap.
Hold RoboCap by its sides. Keep your fingers away from the brim and cameras.
Check that the app confirms:
RoboCap connected
Ready to calibrate
Board squares: Displays the measurement you entered
Once everything is ready, tap Start.
Step 9: Capture the Calibration Pattern
Hold RoboCap with its cameras facing the calibration pattern. Make sure your hands are not blocking any cameras.
Watch the camera previews and calibration progress displayed in the app.
Slowly move and adjust RoboCap's position and angle to bring the calibration pattern into the square boxes shown on the screen. Move closer or farther away as needed.
Keep the calibration pattern visible to the cameras as you move RoboCap. Do not resize the pattern or change its measured square width.
Follow the on-screen tips, which will guide you on how to move RoboCap based on what each camera still needs to capture.
Continue until all six cameras display a checkmark (✓) and the overall progress reaches 100% within 10 minutes. If you don't reach 100% within this time, you'll need to restart the calibration process.
Step 10: Wait for Recalibration to Complete
Once all six cameras have checkmarks and progress reaches 100%, the app will display Enough pictures. RoboCap will automatically begin calculating the new calibration settings.
Put RoboCap down on a stable surface. Keep it powered on and do not start a recording.
Wait while RoboCap calculates the new settings in three stages:
Part 1: Front and eye cameras
Part 2: Left side camera
Part 3: Right side camera
Follow the progress displayed in the app. This step may take approximately 10–20 minutes.
You can lock your phone or leave the app while waiting. RoboCap will continue processing, and you can return to the app to view the results.
Step 11: Check Sampson Error
Once recalibration is complete, the app will display New calibration saved, confirming that the updated calibration settings have been saved to RoboCap.
We recommend checking the Sampson Epipolar Error after recalibration to measure how well the cameras are aligned with the new calibration settings. This helps you evaluate the recalibration results without changing the saved settings.
You can then choose whether to check the Sampson Epipolar Error:
Tap Start measuring to measure the Sampson Epipolar Error and check the camera alignment.
Or tap Not now to skip the measurement.
If you choose Start measuring, wear RoboCap as shown in the app and follow the on-screen instructions. Keep your head still until the measurement is complete.
You can also perform this check later by going to Calibration → Sampson error → Measure now.