Experimental framework of traveling trolley with swinging load for hybrid motion control

A novel experimental framework of the traveling trolley with swinging load is proposed. The system is designed as a controlled moving cart with pendulum for investigation of the hybrid motion control methods, involving the discrete sensors and impulsive event-based state observations and control actions. A mechatronic approach of principal system design, modeling, and identification are provided together with a motion control of the cart and simple event-based control of a-priori unknown final position. The coupled motion dynamics is analyzed and evaluated by using the discrete sensors, along with the control results.

Creep Modeling with Time-Dependent Damping Parameters in Piezoelectric Actuators

This paper develops a creep model based on the Kelvin-Voigt model with time varying damping parameters. In the piezoelectric actuators, the creep phenomenon is an important issue in precise positioning applications as well as the hysteresis property. It is well-known that the creep effect can be represented by a series connection of a number of Kelvin-Voigt elements as a viscoelastic model. In the motion for the continuous stepwise positioning, however, the creep shape is different for each response. Since the phenomenon can be captured as temporal creep relaxation, time-dependent damping parameters are introduced to improve the reproducibility of the creep for the various motion. On the ot…

Estimating Sway Angle of Pendulum System Using Hybrid State Observer Incorporating Continuous and Discrete Sensing Signals

Estimation of Sway-angle Based on Hybrid State Observer Using Continuous and Discrete Sensing

A hybrid state observer design is presented herein to estimate sway-angle and angular velocity in trolley systems with pendulum. In general, anti-sway control for trolley systems with pendulum such as overhead cranes are designed based on sway-angle signals detected by angular sensors. Opposed to that, a state observer without those sensors is proposed to estimate the sway-angle of the pendulum. A standard linear continuous feedback observer causes estimation error owing to the system nonlinearity and modeling error. This paper proposes a hybrid state observer incorporating discrete sensor signals. In the hybrid state observer, the estimation performance is improved by correcting the state …