Robotnačka

History:
The Robotnacka was created in the years 2001 and 2002 at the Department of automation and control at EF SVST in Bratislava. The goal of the project is to design a drawing mobile robot as a physical representation of turtle used in the Logo programming environment: Comenius Logo, Imagine Logo. The robot must have its own power supply and allow exchanging of pens. The operation time must be in at least two hours. The communication with computer should be wireless.

Utilization:
Mobile robot Robotnačka is designed to support educational process in connection with flexible environment of Logo developped at Department of Informatics Education at Comenius University in Bratislava. This environment allows the students to use turtle graphics to learn about programming basics. The central concept of the environment is the virtual turtle, which is programmed by the user.

Construction and control:
Robot kinematics is based on the three-wheeler with a independently propelled wheels. The third wheel is supporting and has minimal friction. Robot is driven by MICROCON stepper motors working in unipolar mode with switched cycle pairs to enhance its torque. The robot features accelerating and decelerating component, which pays attention that no steps are lost during the starting and stopping management of the robot. The motor control is in an open-ended loop.
The central processing unit is the microprocessor ATMEL 89C51, which uses the dual full bridge L298 for both driving the two motors attached to the wheels, and for driving the motor controlling the pen. The pen movement is achieved with bipolar stepper motor with worm gear obtained from a small floppy disk. The limiting positions of the movement are indicated by an optical sensor. The robot contains transmitting/receiving module based on SFH5110 and HDSL4400 and internal charger for its 6V, 4Ah accumulator working in a voltage mode with limiting current.

Technical parameters:

Computer+IR modem :
• Notebook 486/100MHz + Comenius Logo software
• IR modem, 12VDC adapter

Developers:
Ing. Andrej Diosi, Ing Oto Kužma, Ing Dušan Ďurina

Gallery: