Robotizing crop weeding with HKTC and CAPACITES

A user-centric design

"Hand weeding takes up a lot of the market gardeners' time, at the expense of higher value-added tasks" says Oscar Lauby, Director of Development at HKTC. "We want to relieve them of this time-consuming recurring task. "HKTC, a merger of the agricultural machinery manufacturer CARRÉ and the HYDROKIT Group, has designed the first robot for soil hoeing. A concentrate of innovations developed with the support of CAPACITÉS, the engineering subsidiary of the University of Nantes.

"The choice of actuators and electrical components was based on the observation of the end-user" explains Samuel Bonnet, engineer and operational manager of automation and robotics activity at CAPACITÉS. “We thoroughly examined in the field the constraints related to complex outdoor environments and to the conditions of use and safety: irregularities of the terrain and in the shape of the crop plots, irregular positioning of the crops, space available for the turnaround area… ”

Drawing on this field observation phase, their expertise in advanced robotics and the large-scale measurement resources of the LS2N laboratory at the University of Nantes (laser tracker, 2D and 3D camera …), CAPACITÉS experts determined the technologies to be combined to elaborate Anatis.

A powerful trajectory generation algorithm

Combined with two on-board cameras and a geolocation system, the control algorithm that CAPACITÉS developed ensures the autonomous guidance of the robot, which can move from one crop row to another without human intervention. "The control algorithm correlates a pre-programmed trajectory model with the images collected by the cameras, and adapts Anatis' trajectory accordingly", explains Samuel Bonnet.

“Anatis' trajectories are extremely precise. The robot adapts to the specificities of the crop’s soil, to variations of up to 30 cm” adds Oscar Lauby. “With its four-wheel drive, it can easily navigate steep terrain.” The algorithm continuously evaluates the deviations of the robot from the pre-programmed trajectory model. If the deviation is too important, it automatically stops the robot.

A connected autonomous robot easy to control

Designed as a visual application, a human-machine interface (HMI) developed by CAPACITÉS, makes it easy for the market gardener to handle and program the robot. The data collected while the robot is working allows to measure the robot's actions and optimize them. "The robot identifies the most favorable periods for hoeing, by correlating the soil temperature to weather conditions", explains Oscar Lauby.

With this autonomous soil hoeing machine, HKTC has once again relied on innovation to stand out. The company chose CAPACITÉS as its R&D partner because they wanted to benefit from the experience of its researchers and engineers in robotics on the generation of automatic trajectories and the development of innovative HMIs. A successful bet : the Anatis robot evolves in a completely autonomous and secure way in vegetable crops.

 CAPACITÉS  is the engineering and research valorization subsidiary of the University of Nantes.Dedicated to the field of innovation, this subsidiary of 90 employees carries out over 300 engineering and R&D projects per year. It combines and uses high-level skills in robotics and artificial intelligence, to serve your agricultural robotics projects. Its engineers and PhDs work directly with scientists in research laboratories, for the benefit of companies and communities, through customized services such as consulting, expertise and R&D.

Picture: © Anatis, the agricultural robot developed by HKTC with the collaboration of CAPACITÉS