Autonomous mobile robots and AGVs Small drives for the robot learning platform

Related Vendors

FAULHABER Drive Systems

Wuxi InfiMotion Technology Co., Ltd.

In production and intralogistics, autonomous mobile robots (AMR) or Automated Guided Vehicles (AGVs) can become efficiency-enhancing helpers. A robot learning platform now makes it easier for users to get started. The motors used there, with highly accurate gearboxes and encoders, come from Faulhaber.

Upon request from an industrial company, Eduart Robotik GmbH Neunkirchen a. Sand developed a teaching and prototyping platform that can be used for training and further education of employees in handling mobile robotics. In addition to the robot learning platform, the company offers a teaching and service package for testing and optimizing.

Expandable robot learning platform

The resulting robot learning platform is named Eduard, and it measures approximately 40 x 40 x 15 cm and weighs just under 8 kg. A sensor concept including distance and inertial measuring devices is integrated into it, as well as a battery management system. Access is possible via open interfaces. The mobile robot's motion is either powered by simple rubber tires or by Mecanum wheels.

Gallery

Gallery with 5 images

These allow the robot to turn on the spot as well as move sideways or diagonally. Even in very tight spaces, this makes it possible to navigate and position precisely. Faulhaber motors are used in both wheel variants. "These high-quality drives have proven to be optimal for our applications," confirms Markus Fenn, Managing Director of Eduart Robotik GmbH.

Depending on the required speed or torque, gearboxes with a ratio of 72:1 or 89:1 are available for the drive. The basic equipment of the robotic learning platform can be expanded by the user or adapted by EduArt according to individual needs. This makes it possible to cost-effectively test new concepts, such as a different sensor system.

Flexible drive technology

When selecting the drive systems used, it was important to ensure that they would also meet future requirements of AGV (Automated Guided Vehicle) and AMR (Autonomous Mobile Robot) concepts. Therefore, the choice was made for DC micromotors with precious metal commutation from Faulhaber. Despite their small dimensions, these deliver a high torque and impress with their high power density. Moreover, they can be precisely controlled and are suitable for highly accurate control loops. For larger platforms, the robot builders used large DC motors from the same manufacturer. Alternatively, depending on the application, these drives can also be replaced with maintenance-free and long-lasting brushless DC motors.

With the trend towards decreasing batch sizes and increasing variety of variants, more robots will be needed for smaller loads in the future, i.e., smaller robots with smaller but more powerful drives. Such autonomous floor conveyance vehicles have reduced electronic effort and smaller batteries, which means less weight and lower energy consumption. For this too, suitable solutions can be found in the wide range of drive experts from Schönaich. When higher loads are required again, scaling up and working in combination is also no problem.

Easily develop and test software

In AGV (Automated Guided Vehicle) and AMR (Autonomous Mobile Robot) solutions, the complexity usually lies not in the hardware but rather in the software. For instance, good planning on the software side is important so that all mobile robots can work together without problems or reliable fleet management becomes possible. Robots must be able to "think" for themselves, exchange information via standard interfaces, and cooperate if necessary. The software only needs to know little about the particular mobile robot but rather calculate where the robot is located on the hall plan. The navigation, one of the few components that knows the dimensions of the robot, then searches for the suitable path. To achieve the required speed, the motor controller calculates how many wheel revolutions are necessary. Even to adjust this, only a few lines in the program code or a configuration file are needed. Faulhaber provides motors with highly precise gearboxes and encoders for exact positioning, which together bring optimal performance and safety. "The corresponding communication interfaces were also important so that the drives can "exchange" information with the rest of the system accordingly," says Fenn.

Safety is important for mobile robots

Safety is also an important issue when deploying mobile robots, in terms of both security and safety. The latter, for instance, is achieved by the motor controller detecting when one of the motors fails and immediately stopping the journey. If a person steps into the travel area, they are detected by the laser scanner, and the system brakes. Safety is an interesting topic insofar as the individual mobile robots communicate with each other over communication networks such as WiFi or 5G. Appropriate protection mechanisms have been put in place for this as well. Should there still be a hacker attack, it's important that no dangerous movements can be triggered on the robot. For this purpose, robots are equipped with a safety scanner with a distance sensor, for example, to prevent them from crashing into a wall.

A look into the future

In the field of mobile robotics, there will be a lot of developments in the coming years, e.g., in terms of networking. Where, for example, four smaller robots instead of one large one work together on a transport task, small motors are needed that work absolutely precisely. Otherwise, the robot swarm will stumble or get out of sync. To improve fail-safety, encoders must be completely interference-resistant so that the robot is not affected by external disturbances. That's why Faulhaber sometimes uses two encoders per motor. With the further development of mobile robots, the requirements for the drives used will also continually change. Here, it is advantageous that the components of the modularly structured range from the drive experts can be flexibly combined. Theoretically, from the combination of the offered gearboxes, encoders, controllers, etc., 25 million variants are possible, a considerable portion of which has already been implemented in practice. No matter how mobile robotics continues to evolve, an optimal drive can be found for almost every existing as well as future application.