Adaptive Smith Predictor for Teleoperation of UAVs with Time-varying Internet Delay

Time delay in a networked control system can negatively impact the performance of the system. Dynamic networks with unknown and varying latency such as the Internet are studied. Also, experiments with teleoperation of drones and communication loops through the Internet are conducted. Smith Predictors are well known for their ability to handle time delay. Smith Predictor controllers perform well when modeled accurately and when the delay is known. The proposed method combines a delay estimation technique based on characteristic roots of delay differential equations to measure the delay with an Adaptive Smith Predictor. When the delay parameter is adjusted correctly, the negative effects caused by delay are significantly reduced. The proposed method performs satisfactory for networked systems with unknown delay and the results are validated through simulations and experimentation.