In this thesis an implementation of a new driver for educational robot Rob3i is presented. Aim is to use hardware of a broken robot and make it functional once again. The new driver is based on Raspberry Pi version 3 and two Gertbot modules. Original motors, sensors and power supply are preserved. Joint angle measurements are obtained by using A/D converters which convert voltage from potentiometers which are mounted in joints of the robot to enable angular measurements. Sampling is done by Gertbot's A/D converters. To improve the control loop frequency, comunication between Gertbot and Raspbery Pi was adjusted. Control algorythms were implemented in Python with some features relying on BASH shell. Capabilities of the new controller were demonstrated with P, PD and PI controllers. Another control, that which took into the anccount the non-linear property of supply voltage and angular velocity was tested. The tested software allows linear movement of the gripper and saving the control signals into a log file. Some wires are replaced. Excess noise is present in the measurements, however it can be satisfactorily filtered by software. A digital camera is mounted near the gripper. Camera is facing down, towards an ArUco board that is mounted on the workspace. There are large differences detected when comparing the poses obtained from image processing to those of direct kinematics. Further maintainance is recomended on the robot.on the robot.
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