An autonomous robot playing the board game checkers

International Journal of Electrical Engineering Education, Jan 1998 by Zribi, M, Sung, E

The interfacing software enables the robotic arm controller to communicate with the computer via a hardware interfacing circuit and an I/O card. In the course of programming the interfacing software, the students gained experience in performing handshaking using C. The students also learnt to program I/O cards for different port definitions and configurations to suit different demands.

The handshaking protocols between the EYE, BRAIN and HAND modules needed to be very reliable. In the process of experimenting with different handshaking techniques, knowledge of handshaking between different programs was acquired.

During the students' search for software to produce 3-dimensional video graphics in different formats, the students picked up the knowledge of surfing the Internet. They also learnt how to create Video for Windows using the Crystal Flying Fonts software.

To further improve the project, background music, as well as human voices were added to the system. The knowledge of voice recording and playback using sound cards was acquired.

In addition, a feeder and a control panel consisting of a timer, push-button and ON/OFF switch were designed and built. The control panel serves as a link between the human player and the robot for necessary communications. It displays the total time left for the human player. Also, by pushing a certain button, the human player indicates that a move is made. When designing the display panel, the students put to use theories that they had learnt. For example, the students practised voltage regulation, signal inversion and batch counter design.

7.2 Problems encountered during the development of the project

At the early stages of the integration, several problems were encountered. For the integration between the EYE and the BRAIN, the students could not compile the files together because the EYE module used Microsoft C while the BRAIN module used Turbo C. The students tried to convert the BRAIN's program to Microsoft C because the EYE module needed some functions described in pre-compiled files. However, the conversion was unsuccessful. After some consideration, it was decided to compile the EYE programs into executable files, and the BRAIN will just call these executable files when needed. In addition, the BRAIN will provide whatever information is needed by the EYE, by writing that information into files.

There were not many problems between the HAND and the BRAIN. However, in the initial try-out the robot could not execute the moves sent by the BRAIN. This was because the robot received the commands too fast. Before the robot had time to execute a certain move, it would have received the end command and thus did not make any move. This handshaking problem was solved through the addition of some pauses and delays.

Problems were also encountered when integrating the sound function into the BRAIN. The initial software used, SBTalker, was taking up too much of the conventional memory thus causing the system to crash during the try-outs. The problem was solved by using the V play software.