This paper presents a new equivalent-input-disturbance (EID) approach that is the combination of the EID approach and model-predictive-control (MPC) method. The EID approach estimates the influence of a disturbance and uses it to reject the disturbance. Thus, the amplitude of the control input can be beyond the limitation if the original disturbance is large. To solve this problem, this paper combines the EID approach and the MPC method. The MPC method adjusts the amplitude of an estimated EID during a large disturbance. A numerical example uses a structural model and an earthquake. The results of it verify the validity of our method and the presented method has a better control performance than the previous EID approach. Furthermore, the MPC method adjusts the control input lest it is beyond the limitation.

This paper improves the habitability of a building for wind load using an equivalent-input-disturbance (EID) approach. In these few decades, many high-rise buildings are constructed around the world. The influence of wind load is large for high-rise buildings, and it causes a decrease in habitability. Habitability relates to the acceleration of a structural response. To improve the habitability of a building for a wind load, we use a lagged-derivative function and EID approach. An EID approach estimates the effect of a disturbance on an output signal. Thus, an acceleration has to be output to estimate an EID. This paper uses a lagged derivative to output the acceleration. The numerical verification uses a building model of 240m and demonstrates that the presented method suppressed the absolute acceleration and improves the habitability of a building to a wind load.

This paper presents a new design method for an active tuned-mass-damper (AMD) system. A tuned-mass-damper (TMD) is one of the common passive-control methods. A TMD reduces a response for resonance frequency. Recently, an AMD, which applies a control engineering for a TMD, is used to increase control performance. Usually, the TMD and the control system of an AMD are designed separately and some nonstructural member or nonlinear characteristics are ignored. This paper presents a simple method that designs both the TMD and the control system of the AMD simultaneously and considers the uncertainties of a structure. The numerical example uses a single-degree-of-freedom model with an AMD and several earthquake waves. The numerical example demonstrates that the presented method suppresses the displacement without increasing absolute acceleration.

The Ministry of Education, Culture, Sports, Science and Technology, Japan recommended educational institutions in Japan to carry out educational reforms by building active-learning courses. This paper explains the practice of project-based learning for sophomores in the mechatronics course, Tokyo University of Technology. We designed a project to teach simple principles of aeronautics, plant modeling, and mechatronics. Students are required to assemble radio-controlled planes. It tries to gain the motivation in learning mechatronics and the ability of teamwork and communication. We explained how we designed the project and the practical results. Statistics show that this project stimulated students’ curiosity about mechatronics.

An active structural-control strategy has been widely studied to improve the control performance. Most studies used the linear quadratic-regulator (LQR) method to design the state-feedback controller. The LQR method requires to tune many weights in the cost function to design the controller. Moreover, various earthquake waves have to be considered. Thus, it is difficult to determine the weights. This paper determines the weights by using the Bayesian optimization method with multiple earthquake waves to reduces the burden of tuning the weights.

Active vibration control has been widely investigated in civil engineering. This study considers the problem of selecting a norm for an evaluation criterion for the planning of the placement of active damping devices (ADDs) in a structure in active vibration control. Using a 4-degree-of-freedom system as an example, we compare the commonly used 2-norm and ∞-norm, and show that the 2-norm is a suitable choice for the performance index of the placement planning of ADDs.