In this paper, the focus is on ice clamping of workpieces using feedback-controlled Peltier cells, which represents a novel nonlinear control application. As only the hot-side temperature is accessible for measurements, an Unscented Kalman filter (UKF) estimates the temperatures on both the hot and cold sides of the Peltier element and a lumped disturbance heat flow acting on the cold side. These estimates are employed in linearized discrete-time model predictive control (MPC), which is adapted in each time step based on Taylor linearizations around desired trajectories, also considering the predicted future linearization errors, and tracks a given cold-side temperature profile despite interfering heat inflow from the machining process. Here, the nonlinear system model is exploited to calculate favorable desired values that correspond to low currents, minimizing the overall energy consumption and avoiding another possible operating point with high currents. The achieved tracking precision and estimation accuracy is pointed out in simulation results for a typical ice clamping scenario subject to disturbances.

As the drive force depends in a nonlinear manner on the currents, an accurate tracking control of permanent magnet linear motors is challenging. In this paper, a cascaded control is proposed and combined with a recursive estimator. In the inner loop of the cascaded structure, an inversion-based control design is employed in combination with an eigenvalue assignment. The outer loop involves a backstepping tracking control of the armature position, where a nonlinear error dynamics is assigned. Given nonlinear friction and other disturbances, a lumped disturbance force is estimated by a dual Kalman filter – in addition to the state variables. This combination achieves a high robustness of the overall control structure. The control performance is investigated in detailed simulations, where also measurement noise and external disturbances are included.

This paper proposes an estimator-based tracking control for a thermoelectric cooling system with Peltier cells. It is intended for use in a novel manufacturing system leveraging ice clamping. Starting from physical principles and conservation equations, a 4th-order state space model is developed and exploited within an input-output linearization, where the internal dynamics can be shown to be asymptotically stable. A backstepping-based tracking control is designed to accurately track the desired cold side temperature even in the presence of disturbances. Unknown states and disturbances are observed using an Unscented Kalman Filter, which outperforms previous results with alternative estimators. Conclusive simulation results are discussed and demonstrate the performance of the combined control and estimation structure.

Especially in the introductory phase of engineering studies, electrical engineering courses usually reveal a large heterogeneity in the previous knowledge of technical aspects of the students related to practical aspects that are required for successful participation in the labs. During this fundamental orientation phase of the study program, it is crucial to “get your hands dirty” to gain not only abstract, but concrete knowledge of elementary concepts like electrical circuitry and linear supplies.

This paper proposes an adaptive Sliding Mode Control (SMC) strategy using a Model Predictive Control (MPC) for a two rotational joints robot to be used in a tracking problem. The considered tracking problem is the sensorless orientation of a photovoltaic panel with respect to the solar position. The estimated velocity of the sun is obtained by drawing the solar Azimuth and Elevation angle from the Application Programming Interface (API) of a German Metereological Service (meteomatics), providing real time data. The measured data are processed by an Kalman Filter (KF) to estimate the position, velocity and acceleration of the angles of the joints of the robot. The estimated and reference angles and their derivatives are used in the SMC law. Exemplary tracking results are presented at the end.

This paper deals with a Peltier cell used in an innovative manufacturing system with a cascaded Kalman filter (KF) structure to estimate states and parameters to be used in a closed loop control law. While disturbances, states, and parameters of the Peltier cell are estimated online using a cascaded Kalman filter structure, a sliding mode control (SMC) strategy is proposed to maintain the cold-side temperature even in the presence of disturbances. One theorem is given that allows the design of a constructive control strategy. Simulation results are shown and with them the effectiveness of the method.

This Innovative Practice Full Paper presents a constructivist concept for engineering education for non-technical students. Global challenges and transformation processes lead to a rapid increase in problems at the boundary between technical and non-technical disciplines in higher education. Furthermore, new fields of work emerge due to the digital transformation. Graduates need to be prepared to identify and describe problems and to develop appropriate solutions in teams in order to contribute to change processes related to the future in a smart world. Engineering sciences have to take up the challenge to provide suitable educational programs for a broader target group, i.e. non-technical students, especially in light of the current shortage of qualified specialists. This paper contributes twofold to that discourse on transformation processes in Engineering Education: (1) by the development of a theory-based teaching and learning concept on electrical engineering for this special target group of non-technical students; and (2) by presenting the implementation of the undergraduate (bachelor) course with innovative project-based laboratory experiments.

The paper deals with a heuristical approach to compensate friction hysteresis in an aggregate actuator which is proposed to be applied in a camless engine system and which consists of piezoelectric, mechanic and hydraulic components. The hydraulic displacement amplifier shows a conspicuous hysteresis effect that appears to be a dead time that depends on the speed of the engine. In general, with high engine speeds, the dead time effect is reduced. The compensation of the hysteresis effect is not model-based since the real time application must run within a very short time. The presented approach consists of an adaptive pre-action on the desired servo piston trajectory which is generated by a feedforward action fed by phase-variable Gaussian curves as desired valve trajectories. Simulations show the effectiveness of the proposed compensating techniques.

In this paper a model of a hybrid actuator is proposed. It consists of a piezo-mechanical structure (including a hydraulic transmission ratio) and a hydraulic aggregate. Moreover, a cascade control strategy based on Model Predictive Control (MPC) is proposed to track periodic valve trajectory signals. The proposed cascade control structure consists of an internal and an external controller. The secondary, internal controller is needed to accomplish a Soft Landing. The MPCs are combined with two feed forward control actions, one for each part of the model. Simulation results carried out the suitability of the control approach.