It is shown how to obtain asymptotic stability in second-order undamped systems using time-delay action in the feedback of position. The effect of the delay is similar to derivative feedback in modifying the behavior of the system. Results are given on the selection of the controller parameters both in the absence and the presence of additional delay in the feedback path. The time-lag position ...

We present a comparison of a LQR controller and Q-learning on a simulation of a triple inverted pendulum. While the LQR controller was able to balance the pendulum, Qlearning was unable due to memory and computing limitations. We examine the strengths and weaknesses of each method and compare their abilities.

Model Predictive Control (MPC) is used to improve the performance of energy control for swinging up a pendulum. A new MPC method is developed in continuous time, but it explicitly considers its digital implementation letting the control signal be piecewise constant. The stability properties of the algorithm are analyzed in terms of the free MPC design parameters. The achieved performance improv...

The inverted-pendulum system is a favorite example system and lecture demonstration of students and educators in physics, dynamics, and control. This system is a simple and valuable laboratory representation of an unstable mechanical system. This paper traces the early history of the inverted-pendulum system, and also compares several of the early treatments from the literature between 1960 and...

Single-incision laparoscopic cholecystectomy (SIL-C) is a surgical procedure that emphasizes esthetic outcomes. The method used for making the incision in umbilical region, as sole wound site, of utmost importance, not only because it determines outcome, which merit SIL-C, but also greatly influences operability forceps. In large important to reduce restrictions on procedures resulting from int...

The in-plane elastoplastic failure mechanism of plate-tube-connected steel circular arches with inverted triangular cross sections is investigated in this study by using theoretical derivation and numerical simulation. First, the elastic buckling load formula arch under full-span uniform radial (FSURL) presented. Then, limited conditions avoiding connecting plate chord local before global insta...