Summary

• Significant advances in future farm productivity will be enabled by robotics and autonomous systems.
• The incremental gains provided by monolithic tractors and implements with add-on automation such as GPS guidance will be replaced by a step-change in productivity through the use of many small autonomous robots that operate within a whole-farm optimisation context.
• We describe several current projects that demonstrate ground and aerial robots performing two initial applications of agricultural robots: weed maintenance and crop intelligence.
• The key challenge to be addressed in realising the benefits of these new technologies is to 'think beyond the robot' and develop a new logistics and information systems view of farm operations.

Introduction

Australian food production in the 21st century is being asked to respond to significant new demands and pressures (DAFF, 2013). Although current production allows for roughly half of all food produced to be available for export, projections of massively increasing demand from Asia have prompted government to set aggressive targets for production increases. One such target is to increase exports by 45 per cent by year 2025. Because natural resources are limited, achieving such goals must involve increasing the efficiency of production while at the same time engaging in environmental stewardship, and contending with rising human labour costs and diminishing availability of human labour.

Established trends in mechanisation for farming seek increased productivity through ever-larger tractors and implements, and in the last decade, through the use of GPS guidance technology to restrict vehicle impact to precisely defined tracks. The downside of increased vehicle size is that the associated increased weight leads to long-lasting damage to soil structure. The soil under the precisely guided tracks becomes hyper-compacted, leading to substantial and long lasting loss of land productivity.

Concurrently, the number of people engaged in agriculture has been in steady decline for the last four decades (Australian Bureau of Statistics, 2012). The number of farmers in Australia has dropped by 40 per cent since 1981. This decrease is due in part to the reluctance of young people to remain on family farms. Worse, nearly one quarter of farmers are at, or above, retirement age.

In order to increase its competitive position, Australian agriculture and horticulture are beginning to invest heavily in mechanisation and automation through robotics. One of the leaders of Australian agricultural robotics research is the Australian Centre for Field Robotics (ACFR) at The University of Sydney, recognised as one of the largest field robotics groups in the world and one of the largest robotics research organisations. We conduct basic and applied research using both ground robots and aerial robots that is helping to shape the future of farm mechanisation. In this short paper we briefly describe our current work that addresses weed maintenance and crop intelligence. We also discuss the broader role of robotics in an operational context.

Ground Robots for Weed Maintenance and Crop Intelligence

The drawbacks of increasingly large tractors are evident in zero-tillage agriculture. We are involved in a collaborative project with Queensland University of Technology (QUT) and Bendee farm in Emerald, Qld to address these drawbacks through robotics (SwarmFarm, 2013). In this project, we are creating a new robotic vehicle technology that replaces a single large soil-compacting vehicle with many small vehicles that move lightly across the surface without creating significant compaction of the soil or disturbing its protective top layer. The core challenge is to develop intelligent robotic technology that will enable a single operator to manage a team of small vehicles, rather than a single large vehicle. We are demonstrating the capability and benefits of this new robotic technology in its application to weed eradication in broadacre agriculture on 4000 hectares at Bendee farm (Queensland Country Life, 2013). Our prototype robot platform is shown in Figure 1 (left).Another important application of agricultural robotics is crop intelligence, where robots are used to perform autonomous farm surveillance (mapping, classification, detection) and autonomously gather valuable information about crop growth and health. We are working in collaboration with Horticulture Australia Ltd (HAL) to demonstrate the capability of robots in tree crop applications such as almonds and apples, and also in the vegetable industry. Figure 1 (right) shows two ground robots and one aerial robot used in this work. These ideas could also be applied to broadacre agriculture, possibly in combination with weed maintenance. The value of crop intelligence lies in its ability to provide timely and accurate information, such as real-time yield estimates, to support management decisions.

Figure 1: Small autonomous robot for zero-tillage agriculture (top), two ground robots and one aerial robot for crop surveillance in tree-crop applications (bottom).

The Ladybird robot (Figure 2) was designed and developed for the vegetable industry. The focus of the project is to develop an autonomous robot that would assist in gathering and fusing data for advanced crop intelligence, as well as detecting and eradicating weeds using mechanical and precision spraying systems.

Figure 2: Ladybird is an autonomous platform designed for the vegetable industry to research and develop approaches for autonomous weeding and crop intelligence.