the our project in digital control systems is ball & beam as shown in figure (1),A PID controller allows for precise control of the dynamics of a system during transitory and stationary states; This work describes the design of a Ball and Beam platform for testing control algorithms, and the implementation of aparticular PID controller for it. The platform is made out of 2D-wooden parts, an Arduino UNO a PING ultrasonic sensor, a standard servo motor and screws. The controller is implemented in Arduino language and includes proportional,integrative and derivative terms. The system is successfully stabilized; the ball can be positioned at any point within a range of distance. The platform is cheap,easy to replicate and allows for further testing of alternative control algorithms.