2015/2016/2017: Multi Robot Cooperation

Industry 4.0 is the new trend in the economy. Therefore, the students in Lab year 2015/2016/2017 dealt with the project, in which several components interact with each other to solve the overall task.

In the lab year 2015/2016 a simulation of a mining area was set up, where materials should be localized, recorded and then sorted according to good and bad materials. To this end, the tasks should be taken by three different robots, and the robots should match the special requirements of the tasks. A camera, which overlooks the mining area from above, was used in the control the robots and coordination of the interactions. The robots and the camera are connected via a WiFi network.

A self-made robot was designed to transport the components. The students chose a finished rover platform as the basis. Firstly, the power supply of the communication module and the micro controller were setup. Then, the base plate of the robot was sawn and the battery was connected to the charger. The power supply was wired by the students. The programming and wiring problems have been fixed. In the end, the robot could drive straight ahead and turn in a controlled manner.

While one group is working on the self-made robot, the other group is busy building and controlling two Lego Mindstorm robots. The two robots were supposed to work together to collect the rubbles on the field and then sort them. The first robot should run on chains and have a gripper arm at the front to pick up objects. For this purpose, the objects were localized and collected independently using ultrasound. He could also move accordingly if instructed by the camera. The other robot should have a conveyor belt to sort the objects and an elevator with which the object can be transported to the next level.

To control communication between the robot and the camera, a state diagram was set up. The camera locates the robot and then shows it the way to the objects. The image processing was written in C ++ and is based on the open source library "OpenCV". Based on the image captured by the camera, both the angle and the position of the robots will be calculated using QR codes, which the robots can use to navigate effectively.

In the lab year 2016/2017, the students decided on a project in which to build several robots, which can cooperatively accomplish tasks that would not be possible for a single robot.

For example, these tasks could include moving an object that is too heavy for a robot alone. The students are divided in three groups, each group builds a robot. Together, these robots are supposed to do tasks, controlled by the camera.

This year the programming is more in the addressed than the last years, so Raspberry Pi’s should be used for the robots. The "Robot Operating System", or "ROS" for short, is also to be used to control the robots and to simulate their behavior on the PC.