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Using a simulated model of a house consisting of two adjacent rooms, the temperature of the two rooms is controlled with a PI controller and a decoupled PI controller. This is compared to MPC control. In the simulation example here, both the MPC controller and the decoupled PI controller decreased the interaction between the temperature dynamics of the two rooms, as compared to an independent PI c
The use of industrial robots in the aircraft industry has been hampered by a combination of poor accuracy of the robots and poor calibration of the workcell, and also manufacturing variability in composite parts. A way to handle these difficulties is using force control. An experimental case where a semi-compliant rib is aligned to multiple surfaces is used as an example to show this. The constrai
Theory for Adaptive Nonlinear Model Predictive Control is developed based on the relaxed dynamic programming inequality. The adaptivity in the controller lies in the choice of control horizon. The control horizon is chosen such that a variation of the relaxed dynamic programming inequality holds for all time steps along the closed loop trajectory. This provides guarantees for asymptotic stability
Composition is a practice of key importance in software engineering. When real-time applications are composed it is necessary that their timing properties (such as meeting the deadlines) are guaranteed. The composition is performed by establishing an interface between the application and the physical platform. Such an interface does typically contain information about the amount of computing capac
Tight human-robot interaction and collaboration will characterize future robot tasks. Robot working environments will be increasingly unstructured, as safety barriers will be removed to allow a continuous cooperation of robotic and human workers. Such a working scenario calls for novel safety systems capable of combining productivity with workers’ safety. In this paper, a method for the definition
In this paper we investigate a system for tracking the motion of box jellyfish tripedalia cystophora in a special test setup. The goal is to measure the motor response of the animal given certain visual stimuli. The approach is based on tracking the special sensory structures – the rhopalia – of the box jellyfish from high-speed video sequences. We have focused on a realtime system with simple bui
Time-triggered periodic control implementations are over provisioned for many execution scenarios in which the states of the controlled plants are close to equilibrium. To address this inefficient use of computation resources, researchers have proposed self-triggered control approaches in which the control task computes its execution deadline at runtime based on the state and dynamical properties
With larger penetrations of wind power, the uncertainty increases in power systems operations. The wind power forecast errors must be accounted for by adapting existing operating tools or designing new ones. A switch from the deterministic framework used today to a probabilistic one has been advocated. This two-part paper presents a framework for risk-based operations of power systems. This framew
Operating criteria for power systems, such as theN−1-criterion, are often based on evaluating whether the system is vulnerable to a specific set of contingencies. Therefore, a major part of power system security is concerned with establishing regions in parameter space where the system is vulnerable to specific contingencies. In this article we exploit the possibility of using Monte Carlo simulati
Guaranteeing stability of control applications in embedded systems, or cyber-physical systems, is perhaps the alpha and omega of implementing such applications. However, as opposed to the classical real-time systems where often the acceptance criterion is meeting the deadline, control applications do not primarily enforce hard deadlines. In the case of control applications, stability is considered
The problem of modeling and controlling re- sources in a system with interaction between hardware and software is considered. A model encompassing both hardware and software dynamics is developed together with an on- line estimation scheme in order reduce dependence on a- priori information. A control structure is presented in order to control performance under constrained resource situations and
Grafchart is a graphical programming language for sequential control applications. It exists in two versions: the basic version (BV) and the high-level version (HLV). The currently used Grafchart tool, JGrafchart, only supports BV. To enable further research on HLV, it must be supported by JGrafchart. Since HLV is a superset of BV it is desirable to add it as an extension to the current implementa
The problem to minimize power losses in an electrical network subject to voltage and power constraints is in general hard to solve. However, it has recently been discovered that semidefinite programming relaxations in many cases enable exact computation of the global optimum. Here we point out a fundamental reason for the successful relaxations, namely that the passive network components give rise
