The Development of an Autonomous Robotic System for Playing Mini-Golf.

Abstract

This article describes the development of an autonomous robotic system for playing mini-golf. The system was designed and built to serve as a demonstration of robotic application for engineering students. The system was built using a Yasakawa robot fitted with two arms. Software was developed to control the machine using the C++ Language. Standard C++ libraries were used in addition to communication libraries provided by the Yasakawa Corporation. The current configuration works with Microsoft Windows NT and an Ethernet environment. This article describes the hardware and software design aspects of this machine. A survey of the literature showed that several authors have developed robot-based games. These include a system for playing with a yoyo [1], playing volley ball [2], playing chess [3]-[4], playing ping- pong [5]-[6], and for juggling balls [7]. No work was reported on a system to play mini-golf. Machine Description The robot (Yasakawa RobotWorld Model RW-05) used for this project has two arms, each with four degrees of motion. These consist of x, y, z, and roll motion. The base of each arm slides on the surface of a magnetic platen and is separated from the platen by a thin layer of air. The design of the robot system resembles an “air hockey” configuration, therefore, each arm will be referred to as a puck. The first puck serves as the putter and has a plastic toy putter mounted at the end of its roll axis. The second puck has an optical throughthe-beam light sensor mounted on a machined metallic bracket that is attached to its roll axis.The sensor is used to locate the position of the ball when the second puck scans the course surface. The ball that is used for this system is 1.3-in in diameter, made of hard plastic, and smaller than a normal golf ball. Figure 1 shows a picture of the developed system. The course is built using green turf carpet mounted on the top of a 2.5-in thick rectangular piece of Styrofoam.The course sets on the top of the robot base.To prevent the ball from falling of the course edge, a slanted border was placed around the course. The “green turf ” area is 44.25 in long by 24 in wide. This area is larger than the reachable workspace of the two pucks. The playing area is a subset of the green turf area and is 39.5 in long by 20.5 in wide. A metallic wire placed about 1/2 in off the course surrounds the playing area. The wire fence is placed at the travel limits of the two pucks. Four holes, each with a diameter of 1.8 in, were drilled in the carpet/Styrofoam base at approximately the middle two-thirds area of the course.Within each hole,a hollow plastic tube with a 1.6-in inside diameter was fitted to each of the holes. Within each hole,a pneumatic ejection system (see Figure 2) was built to eject the ball from the hole. The ejection system is based