Design of a Prototype Autonomous Forestry Extraction Machine
Type of content
Executive Summary: The purpose of this project was to design and build a prototype autonomous forestry extraction vehicle and demonstrate the feasibility of integrating an autonomous control system on a forestry forwarder. Forestry in Australasia is a multi-billion-dollar industry and provides opportunities for autonomous vehicles with the potential to improve efficiency, productivity and worker safety and health. The use of autonomous vehicles to support industry processes is not a new concept. For over 10 years they have been successfully used in the mining industry carrying ore from the mining site to the processing area. The process of transporting material from an extraction site to a sorting and distribution area following a consistent route is common throughout many industries, including forestry. Log extraction from the tree felling area to a loading site and returning for another load is a typically repetitive task and has been identified as well suited for early adoption of autonomous vehicles. Technology integration and semi-automation in forestry equipment is becoming commonplace (such as integration of hydraulics, cameras and remote control in a motorised grapple carriage for cable logging). This project focussed on opportunities to develop equipment with autonomous control; that is without direct control of a human operator. Introducing autonomous forwarders has the potential to improve safety and worker health, extend working hours and providing all year round wood supply, increasing annual production and reducing operating costs in the forest industry. In addition, less experienced operators can help manage autonomous forwarders providing a solution to the present shortage of skilled machine operators. As a first step to achieving these goals, a small prototype wheeled vehicle was built to provide a platform for testing the electrical componentry necessary to achieve autonomous functionality. Construction of the prototype began by modifying a low cost wheeled trolley to serve as a mobile platform and installing a chain drive system. This provided drive and differential skid steering functionality. The integrated sensor system included GPS for guidance and LiDAR for obstacle detection. The GPS unit provided location and compass direction, which gave the prototype a heading and approximate distance from a predefined waypoint. The electrical system was designed to include an electrical board to mount a microcontroller to interface with the obstacle detection sensors. A primary scope change removed the requirement for the prototype to self-navigate around detected obstacles. Instead, the prototype would simply stop movement and provide live video feedback using of an optical camera. A remote operator would then move around the prototype obstacle and subsequently then continue its autonomous travel. The present functionality of the prototype includes remote control operation of the motors, and basic collision avoidance. GPS guidance is provided by inputting a path through waypoints and wireless camera feedback to a smart phone screen has been achieved. While further testing and refinement would be required to consider the project a success, overall the project has demonstrated that basic autonomous movement of extraction machines such as forwarders can be readily achieved with relatively low-cost existing technology.
Ngā upoko tukutuku/Māori subject headings
ANZSRC fields of research
Fields of Research::40 - Engineering::4007 - Control engineering, mechatronics and robotics::400703 - Autonomous vehicle systems
Fields of Research::40 - Engineering::4002 - Automotive engineering::400203 - Automotive mechatronics and autonomous systems