The thesis presents a novel Internet-based controller designed with the remote controller computer synchronizing its clock with the local computer. An observer-based state feedback control strategy is proposed to compensate the Internet delay and improve the system performance. Asymptotic stability of the closed-loop system is achieved without the assumption of reliable transmission from the controller computer to the local computer, which reduces the requirement for high performance Internet access. Computer simulations are conducted to evaluate the proposed control strategy, and the results have confirmed its effectiveness. The experimental results have demonstrated the supreme performance of the proposed control strategy.