A lightweight, cost-effective 3D spatial mapping device designed for indoor exploration, using a Time-of-Flight (ToF) sensor as an alternative to traditional Light Detection and Ranging (LiDAR) systems. The system combines the MSP-EXP432E401Y microcontroller, VL53L1X ToF sensor, and a 28BYJ-48 stepper motor to generate layered y-z slices of the scanned environment, which are manually displaced along the x-axis to form a complete 3D representation.
Nathan Chan
Email: nathanchan.1738@gmail.com
GitHub: github.com/NathanElectronics
Please report bugs or enhancement requests at:
nathanchan.1738@gmail.com
- Real-time plotting speed may vary based on PC specs and serial buffer performance.
- Limited range in strong ambient lighting conditions due to sensor saturation.
- Manual x-axis displacement requires user calibration between layers.
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Hardware Requirements:
- MSP-EXP432E401Y LaunchPad
- VL53L1X Time-of-Flight sensor
- 28BYJ-48 5V stepper motor
- ULN2003 driver board
- Power supply (e.g., USB or external regulated 5V)
- Push buttons, onboard LEDs (preconfigured on LaunchPad)
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Software Setup:
- Install Keil uVision or compatible ARM compiler.
- Clone this repository:
git clone https://github.com/nathanchan/tof-spatial-mapper.git
- Flash the provided firmware to the MSP432 via Keil or TI Code Composer Studio.
- Ensure VL53L1X is connected via I2C and the UART pins are wired to the PC serial port.
- Power on the device — onboard firmware initializes LEDs and button input.
- The VL53L1X sensor begins capturing distance readings by emitting pulses and processing reflected light using internal ADC and filtering.
- Distance data is transmitted from sensor to MSP432 via I2C, and then from the MSP432 to the PC via UART at 18 MHz bus speed.
- The PC reads UART data and computes y-z coordinates based on the stepper motor’s angular position.
- After completing a layer, manually shift the x-axis for the next scan layer.
- Use MATLAB or Python scripts to render a 3D spatial map from accumulated slices.
Testing is currently manual and performed as follows:
- Validate stepper motor calibration by performing a full 180° sweep and checking scan spacing.
- Ensure UART values align with known distances using reference objects.
- Test the 3D plotting pipeline in MATLAB or Python:
- Compare known wall distances or corners for visual accuracy.
- Adjust trigonometric conversions if necessary.
Future work includes automated scanning and integration with motor encoders for x-axis stepping.
This project is released under the MIT License. See LICENSE for details.