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C · STM32 · SPI · Python · Blender · Embedded

STM32 Gyro 3D Plane Visualizer

CSTM32SPIPythonBlenderEmbedded

Overview

A full-stack embedded-to-3D pipeline that translates physical motion into a real-time 3D environment. The STM32 reads raw angular velocity from an L3GD20H gyroscope via SPI, transmits parsed data over UART, and a multi-threaded Python script animates a 3D F-15 aircraft model in Blender with zero perceptible latency.

Architecture

[L3GD20H Gyroscope] ──SPI──► [STM32F429] ──UART──► [Python Script] ──► [Blender 3D Model]

Technical Highlights

  • Bare-Metal SPI: Uses STM32 HAL for efficient burst reads, capturing X, Y, and Z axes simultaneously.
  • Optimized UART: Fixed-point arithmetic formats and transmits sensor data, intentionally bypassing heavy floating-point printf to save MCU flash.
  • Real-Time Integration: Converts raw angular velocity (°/s) into absolute Euler angles (Pitch, Roll, Yaw) on the fly using numerical integration: θ_current = θ_previous + (ω × Δt).
  • Multi-Threaded Engine: Background daemon thread + Blender Modal Operator parses live serial data without freezing the 3D rendering UI.
  • Deadband Filtering: Customizable noise threshold prevents model drift from inherent sensor noise.
gyro_spi_read.c 
/* Burst-read X, Y, Z angular velocity registers via SPI */
uint8_t tx_buf[7] = { 0xA8 | 0x80 | 0x40 }; /* auto-increment + read */
uint8_t rx_buf[7];

HAL_SPI_TransmitReceive(&hspi5, tx_buf, rx_buf, 7, HAL_MAX_DELAY);

int16_t raw_x = (int16_t)(rx_buf[2] << 8 | rx_buf[1]);
int16_t raw_y = (int16_t)(rx_buf[4] << 8 | rx_buf[3]);
int16_t raw_z = (int16_t)(rx_buf[6] << 8 | rx_buf[5]);

Demonstration