Semi-Automated Undervine Slasher Development
Abstract
Automation in vineyards is a necessity; however, there exist several challenges, such as harshness of vineyard unique environment which makes vineyard automation not a simple process to undertake. This project aims to develop a Semi-Automated slasher system which enable farmers to attain a better, faster, more cost-effective slashing with minimum supervision. The development of the smart under-vine slasher is a proof-of-concept design to show the feasibility of viticulture automation in a simple application. The design is successful in demonstrating this, proving further industrial automation may also be feasible.
Summary
With the advent of the fourth industrial revolution, intelligent systems have been created to solve traditionally complex tasks. As the viticulture industry in Australia generates over $13 billion annually and supports over 172,000 jobs, Ledgard Pruning Systems in conjunction with Flinders University have determined that the development of a semi-autonomous under-vine slasher will continue to support and foster the growth of the Australian viticulture industry.
Although under-vine slashing technology is largely primitive, intelligent systems from a variety of industries have been analysed to guide the innovative semi-autonomous under-vine slasher’s control system. In general, an intelligent control system functions in three distinct phases, a sense phase, plan phase and act phase. The sense phase of the control system was developed utilising the mechanism produced by Ostojic. An investigation was undertaken into the sensing mechanism’s performance to ensure the reliability of the control system. It was determined that to increase system reliability, pull-up resistors had to be added to the membrane potentiometers used to detect vine collision to reduce the impact of noise. A LiDAR running in conjunction with Hector SLAM was used to measure system displacement instead of an IMU due to the increased accuracy afforded by the LiDAR.
The plan phase of the control system operates in real-time to create an ideal path for the system.
As the hydraulic actuator (which physically controls slasher head movement) is fed by a three-way valve at a constant flow rate, the act phase of the control system was developed as three-state on-off controller incorporating hysteresis. A hydraulic actuator was not made available for experimentation and as a result, the performance of the controller was tested utilising a dynamic mathematical model, replicating the response of the system in the possession of Ledgard Pruning Systems.
Each phase is then combined to create an intelligent, “smart” slasher that is capable of avoiding vines.