Our robot takes over the task of R1 (see task definition [only available in German]). In order to fulfil the task, we have divided our robot into 3 sub functions. Chassis/housing, arm, gripper.
The entire control of the robot ist done via the PCB and the microcontroller
chassis / housing
The robot only needs to be able to drive forwards and backwards. Steering is not necessary. One condition is that the robot is properly aligned at the beginning. A template is used for this purpose
The chassis is mad of sheet metal and milled components. The wheels are 3D printed parts, which are equipped with an O-ring made of tyres. One axle is driven by a DC motor.
At the bottom of the chassis is an IR sensor which detects the black trackmarks on the ground of the playing field. In addition there is an IR distance sensor which detects a hole in the sheet metal when crossing the "river" and thus knows when it is in the middle of the "river"
also mounted on the chassis is the housing that connects the individual components to each other. The housing also enables the connection with the partner robot by means of three magnets
In order to be able to grip the pipe or lower itself onto the rail during evacuation, the robot must be able to move its gripper back and forth and swivel through 90°. These functions are performed by the arm.
Moving the arm back and forth is done with a toothed rack and a DC motor with encoder. Swivelling the arm by 90° is also made possible with a DC motor with encoder. The challenge in swivelling was to be able to adjust the speed and power of the motor. A gearbox was installed for this purpose.
The function of the gripper is to be able to grip the pipe and at the same time to move the pipe back and forth.
The gripping itself is done with a movable and a fixed jaw, where both jaws have 2 rollers. To prevent the pipe from sliding out of the pipe, a rubber wheel presses against the pipe. The rubber wheel is coupled to a DC motor with encoder which can move the tube back and forth in the gripper.
In the gripper there is also a microcode reader which reads the microcode on the tube to determine the length of the tube.
PCB (Printed Circuit Board)
The PCB contains all the electrical components that are required for the use of all sensors and motors. The rough division of the print is as follows: in the upper area there are the power components (motors) and in the lower area the control electronics (sensors). For the 5 motors with encoders we use 3 motor drivers. The W-LAN module is easily accessible on the front side of the print plate. The battery is mounted on the floor behind the print plate and can be charged via a cable.
The design of the microcodes was realised with the help of AutoCAD software. The codes were then produced in the clean room by lithography. Each of the microcodes, with an area of approximately four by four millimetres and a thickness of around one millimetre, consists of 100 individual symbols, whereby three different symbols were used in each case. The symbols, which are just 270 micrometres in size, have to be read by the robot's camera for the task.