Accurate control of a low-cost soft robotic arm for automated strawberry picking


Philip Johnson

Philip studied for his BEng in Mechanical Engineering and MRes in Agri-Food Technology at the University of Lincoln. His PhD project focuses on the development of ‘soft-robotic’ harvesting technology for the picking of soft fruits.

The harvesting of U.K. soft fruits is currently heavily labour-intensive, employing thousands of seasonal fruit pickers, who are becoming increasingly difficult to recruit due to the unattractive nature of the job, seasonal demand and the changing political situation. Recognising the challenges in recruiting sufficient human pickers, the industry is under significant pressure to consider automating the harvesting of strawberries via novel robotic solutions. Soft robotics is an emerging field of robotics which utilises soft materials and mechanisms to create entirely compliant robots. This technology is ideal for the requirements of soft fruit harvesting such as delicate handling and grasping in cluttered, unstructured environments.

The generalised aim of this project is to develop and control a novel, low-cost, soft robotic arm manipulator for harvesting soft fruits. The manipulator should ideally be suitable for deployment on a separate mobile robotic platform.

Current research objectives

1. Build upon variable stiffness principles to develop a novel mechanism for strengthening the grasp of a soft robotic harvester whilst also retaining soft properties at rest.

2. Design a soft robotic end-effector capable of ‘snap-picking’ a strawberry

3. Develop control methods allowing the soft robotic manipulator to grasp a target strawberry within a realistic, clustered growing environment.

Research progress

Philip Johnson AHDB Annual Report 2022

Philip Johnson AHDB Annual Report 2023