High Altitude Remote Sensing for Agricultural Applications – Imager Scanning System

The Problem

High altitude pseudo satellite (HAPS) can fill the gap between satellites and drones by providing continuous, automated, and very high-resolution imagery of crops, and can operate autonomously, potentially providing the ideal imaging platform for agricultural remote sensing. Due to the harsh environmental conditions and sophisticated optics required for capturing images of Earth from the stratosphere there an array of engineering challenges to be overcome. A crucial requirement for a HAPS imager is the ability to scan the Earth’s surface via pan and tilt functions as the balloon is moving. This scanning needs to occur continuously and autonomously.

The Solution

To address the problem statement, we have developed an actuated gimbal mirror assembly with communication and control algorithms implemented using the ROS2 framework. The control provides low noise/jitter movement using advanced robotics actuators to prevent image noise and distortion. Scanning is performed autonomously in case remote communication goes down or is not reliable. We can also remotely adjust scanning speeds, angles and acceleration profiles to optimise image capture during missions. The scanning sub-system integrates seamlessly with the image capture and processing unit to synchronise these two functions. The scanning assembly has also been designed to withstand harsh conditions, namely minimal thermal convection and sub-zero cold starts. We are currently in the process of using standard and bespoke testing protocols to validate our system and move into the final design stages.

Collaborators

Mechatronics Engineer (Brian Smith) – Software development of ROS2 control drivers and hardware calibration and tuning.

Mechatronics Engineer (Eugene McNearney) – Mechanical design of gimbal assembly and hardware selection/specification.

Mechatronics Engineer (Michael Salim) – System design of software architecture and hardware selection/specification.

This Imager Scanning System project is linked to the “High Altitude Remote Sensing for Agricultural Applications” project.