Overview

Problem Statement

Our goal is to develop a lightweight gimbal and camera that can be mounted on cheaper drones that cannot accommodate larger loads of larger gimbal and imaging systems. We aim to build a prototype three-axis gimbal and imaging system that weighs under 350 grams and costs less than $200.

 

High Level Design

Motor Control System:

 

Inertial Mass Unit (IMU)

  • Combination of a gyroscope and accelerometer
  • Measures angular postion data in yaw, pitch and roll

Motor controller

  • Reads angular position data from an IMU that informs the controller of the changing position of the body that the drone is attached to.
  • Sends PWM signal to drive motors into a position to offset movement

Servo Motors

  • On board encoder allows servos to rotate to a set position
  • Each corrects for an axis (yaw, pitch or roll)

Position Control Algorithm

  • After IMU has stabilized, it records the yaw position
  • It sets the motor postion to 90 degrees (the midpoint)
  • Reads yaw, pitch and roll from the IMU using Jeff Rowberg’s MPU-6050 library
  • Writes the position to the servos: (90) – the measured angle + the offset

 

Imaging System:

 

Pi Camera:

  • Capable of taking still photos at 8MP or taking 1080p (at 30 frames a second)

Raspberry Pi Zero:

  • Lightweight and compact, the microprocessor accesses the camera and stores the files on an attached micro SD card