System

The Curt robot family is a research project for a more environmentally friendly, economical and sustainable agricultural industry. The system can assist especially in the protection of crops, but also in the precise fertilization of individual plants and in aspects of the harvesting process. Part of the research is the implementation of autonomous fleet control and wayfinding, but also the integration of electric driving and low vehicle weight to protect the environment.

Curt Mini

The Curt Mini is the smaller of the two robots. It functions as a versatile platform for attaching, testing and collecting data from various sensors. The robot is designed to make this functionality as easy as possible to use in the field. For this purpose, there is an onion design on whose outer layer the sensors can be attached from the inside. The second layer protects the sensitive electronic components from environmental influences such as rain and dust

To ensure uninterrupted use without getting stuck or falling over, the robot is equipped with a rocker kinematic. This is used in a similar way on Mars rovers to enable the robot to overcome rough terrain. This allows hazardous terrain to be explored autonomously and from a remote location, e.g. for disaster control. The main purpose, however, is to enable farmers to collect data in the fields to identify malicious plants.

Curt Maxi

The larger of the two robots is Curt Maxi. It has a similar system that can also attach various sensors to detect pests in the field. In addition to its detection instruments, the robot also has an actuator system that enables it to precisely remove weeds. Thus, crops can be accurately protected without the use of pesticides that are harmful to the environment and humans.

In the students' work, it was particularly important for the research institute that both concepts could be implemented in an economical and simple approach in order to be ready for use in research. For the Curt Maxi, the focus was on a design that would not cause fear among bystanders despite its size. It was also important that users could easily access all areas, for example to replace sensors or batteries of the robot in the field.

Environmental Problems

In agriculture we use many practices that are harmful to our environment and our food. For instance, the use of pesticides is toxic to both crops and the environment, and contaminates our groundwater. The extensive and excessive use of fertilizers is an additional burden for the nature and groundwater. The use of heavy machinery in agriculture not only damages the soil on which the plants are supposed to grow, but also causes a lot of CO2 to be emitted.

Curt Project

The idea of the Curt project is to use autonomous robots with intelligent software to support the growth of crops in a more environmentally friendly way. In order to realize this vision, not only properly adapted and capable robots are needed, but also intelligent software that can find its way around the environment. In addition to localization, this also requires recognition of the environment and obstacles. Furthermore, the software of the robots should be able to recognize harmful plants in order to remove them.

The implementation of the system is therefore very dependent on collecting enough data that can be used to train artificial intelligences to perform exactly these functions. To make data collection easy and economical, we have a small robot in the Curt system, the Curt Mini, which is designed to test different sensors and collect data with them. In order to be able to move as steadily as possible in the field, the Curt Mini has rocker kinematics that allow it to overcome high obstacles. At the same time it compensates for these movements so that the sensors are aligned in a relatively stable manner.

If enough data can be collected for autonomous function, the larger of the two, Curt Maxi, can also operate in the environment. It will be equipped to take over various tasks in pest control, fertilization and harvesting. For this purpose, the Curt Maxi has a size that allows it to reach over two rows of plants in width and height.

Design

In the design process, we had to pay attention not only to economic feasibility for the institute, but also to a good external appearance of the robots. Since the robots are intended for autonomous and unsupervised use, a friendly aesthetic was very important. In addition, it should be possible to understand from a distance what the robot is about and what its function is. The size of the Curt Maxis can be quite intimidating, which is the reason why we took great care to avoid a military aesthetic. Furthermore, the context of agriculture should be recognizable, but at the same time the design should also distinguish the degree of innovation of the Curts from the rest of agriculture industry.

For the use of the robots, the focus was particularly on farmers and researchers who will need the robots in the early stage of development. It is particularly important that sensors can be easily adjusted and replaced out in the field. For this, many functions had to be clarified, for example how to attach the sensors very flexibly but still safely, with as few tools as possible, in order to be able to carry out these actions in the field. Furthermore, a large accessibility of the components on the inside of the robots was important. Here, the sensors must be connected to computers for perception and actuation. We brought together the great accessibility with simultaneous safety of the internal components and great flexibility in an onion shell concept. This has several layers that provide individual functions but still allow good accessibility.

For the research institute, the main focus was to be able to test the design of the robot quickly and to ensure good functionality without having to spend a lot of money. For this purpose, we have always paid attention in the design process to a simple manufacturability, which does not require special tools and can be executed anywhere in the world. Furthermore, we made sure to use as little material as possible and to incorporate as many functions as possible into the existing components. In the end, we managed to have the two robots consist of only 2 dimensional bent metal sheets that require few welds. We were thus able to make the design of the two curts very economical, but also easy to implement, easy to use and aesthetic.

Process

In the project, we as a group of students supported the Fraunhofer research institute in the design of the robots. For this purpose, we first did a broad research, but due to the high degree of innovation of the project, we had to look into many distant areas. In the project, the research institute talked to many potential users to clarify the needed functionalities exactly. Furthermore, we looked at comparable robots and tested them for aesthetics and functionality. In doing so, we noticed many hurdles in the configuration and the adaptation. Furthermore, we were able to gain knowledge about the functionality of the robots through already existing Most Viable Products of the research institute.

The design process was driven by model building and especially the use of virtual reality. The technology allowed us to build rapid iterations at full scale, that could be quickly tested for functionality and aesthetics. Furthermore, in our design process, we were in constant communication with the research institute and engineers who were able to test our proposals for stability and feasibility. For successful implementation, we accompanied the concept up to the final production.

Outcome

The design of the robots has enabled the institute to present current research results at trade fairs and will hopefully contribute to new research results in the future. The design should increase the interest and attention for the research project. Furthermore, it should make the research work easier and enable other user groups to use the robots and gain research results in new application areas. The design of the robot makes it possible to use one platform for many different purposes and to exchange components easily. This makes the robot not only more versatile but also more long-lasting.

In the long run both robots can contribute to increase the knowledge about our agriculture. This should result in the automation and precision of operations that are currently carried out with pesticides or by hand. The research project is at the forefront of making the agricultural industry more sustainable and providing a healthier environment and nutrition.