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An implementation of the spectral estimation method presented in Bagge Carlson et al. "Linear Parameter-Varying Spectral Decomposition." 2017 American Control Conference.
Provides implementations of Ijspeert et al. 2013 and of Martin Karlsson, Fredrik Bagge Carlson, et al. 2017
A Julia toolbox for approximation of functions using basis function expansions (BFEs).BFEs are useful when one wants to estimate an arbitrary/unknown/complicated functional relationship between (in the simple case) two variables, y and v. In simple linear regression, we might consider a functional relationship y = ϕ(v) = αv + β, with parameters α and β. However, if the function ϕ has an arbitrary
Solves the same problem as iLQG, with an added constraint on the KL-divergence between the new trajectory distribution and the distribution induced by a previous controller. This feature can be used in an outer loop with repeated experiments between the iterations if the model used for optimization is uncertain.
This toolbox works similar to that of other major computer-aided control systems design (CACSD) toolboxes. Systems can be created in either a transfer function or a state space representation. These systems can then be combined into larger architectures, simulated in both time and frequency domain, and analyzed for stability/performance properties.
Future district heating systems (so called 4th Generation District Heating (4GDH) systems) have to address challenges such as integration of (de)centralized renewable energy sources and storage, low system temperatures and high fluctuation of the supply temperature. This paper presents a novel framework for representing and simplifying on-grid energy systems as well as for dynamic thermo-hydraulic
In conventional seismic surveys, there is a waiting time between sequentially fired shots. This time is determined such that the deepest reflection of interest is recorded before the following source is fired. In a survey with simultaneous or blended sources, the waiting time between the firing of shots is not dependent on the deepest reflection of interest, it is usually much shorter and/or can h
An algorithm for high-performance path tracking for robot manipulators in the presence of model uncertainties and actuator constraints is presented. The path to be tracked is assumed given, and the nominal trajectories are computed using, for example, well-known algorithms for time-optimal path tracking. For online path tracking, the nominal, feedforward trajectories are combined with feedback in
Particle methods such as the particle filter and particle smoothers have proven very useful for solving challenging nonlinear estimation problems in a wide variety of fields during the last decade. However, there are still very few existing tools available to support and assist researchers and engineers in applying the vast number of methods in this field to their own problems. This paper identifi
Industrial robots typically require very structured and predictable working environments, and explicit programming, in order to perform well. Therefore, expensive and time-consuming engineering work is a major obstruction when mediating tasks to robots. This thesis presents methods that decrease the amount of engineering work required for robot programming, and increase the ability of robots to ha
The relay autotuner for PID control is based on the simple idea of investigating process dynamics by the oscillation obtained when the PID controller is replaced by a relay unction. In this paper an asymmetric relay function is used, which provides an equation for the static gain of the process. A method to find the normalized time delay is proposed and the benefits of this is discussed. Ways to f
The current virtualization solution in the Cloud widely relies on hypervisor-based technologies. Along with the recent popularity of Docker, the container-based virtualization starts receiving more attention for being a promising alternative. Since both of the virtualization solutions are not resource-free, their performance overheads would lead to negative impacts on the quality of Cloud services
Modern software applications are subject to uncertain operating conditions, such as dynamics in the availability of services and variations of system goals. Consequently, runtime changes cannot be ignored, but often cannot be predicted at design time. Control theory has been identified as a principled way of addressing runtime changes and it has been applied successfully to modify the structure an
A systematic approach to the analysis and design of a class of large dynamical systems is presented. The approach allows decentralized control laws to be designed independently using only local subsystem models. Design can be conducted using standard techniques, including loopshaping based on Nyquist and Popov plots, H methods, and μ-synthesis procedures. The approach is applied to a range of netw
Modern computing systems are often formed by multiple components that interact with each other through the use of shared resources (e.g., CPU, network bandwidth, storage). In this paper, we consider a representative scenario of one such system in the context of an Internet of Things application. The system consists of a network of self-adaptive cameras that share a communication channel, transmitt
We present our successful efforts to improve intuitive programming of synchronized dual-arm operations in industrialrobotic assembly tasks. To this end we extend an earlier proposed skill representation (based on our work with ontologies for industrial robots) and our respective programminginterface to integrate options for the specification, adaptationand refinement of synchronization points, syn
Distributed algorithms for solving coupled semidefinite programs (SDPs) commonly require many iterations to converge. They also put high computational demand on the computational agents. In this paper we show that in case the coupled problem has an inherent tree structure, it is possible to devise an efficient distributed algorithm for solving such problems. The proposed algorithm relies on predic
Cloud computing technology provides the means to share physical resources among multiple users and data center tenants by exposing them as virtual resources. There is a strong industrial drive to use similar technology and concepts to provide timing sensitive services. One such domain is a chain of connected virtual network functions. This allows the capacity of each function to be scaled up and d
Common harmonic oscillator topologies, such as class-B and class-C, are typically unable to meet ultra stringent phase noise requirements, due to the exceedingly large capacitance (and, symmetrically, low inductance) that would be required in the parallel resonator. In this paper, we show that an oscillator making use of series resonators is ideally able to overcome this limitation, with the addit
