J. Mast, Z. Liu, Z. Wang and O. Stursberg: "A Unified Approach to Communication Delay and Communication Frequency in Distributed State Estimation of Linear Systems", IEEE Control Systems Letters, vol. 7, pp. 2755-2760, 2023



This paper introduces a novel method to address communication delay and communication frequency in distributed state estimation using a unified structure. Starting from a general type of delay, which can be time-varying, unknown, and different for each channel, two estimation strategies are proposed which use either a unified upper-bound of the delay in all channels, or a sender specific upper-bound in order to improve the performance. The strategies guarantee convergence of the estimation error, and they can be applied to study how communication frequency (or asynchronous communication) affects the convergence rate of the estimation. Thus, the task of determining a necessary communication frequency for obtaining specified performance of distributed estimation is considered, and this task is approached as a special case of the one tailored to delay. Effectiveness of the techniques is confirmed by numerical examples for both types of tasks.



  abstract = {Processes of additive manufacturing by 3D-printing are typically operated by only using constant references for feed motion and laser power. For adapting properties of workpieces to desired geometries, the control towards changing reference signals is an enabling factor, though. With a focus on temperature control, this paper proposes a scheme of model predictive control for 3D-printing with consideration of constraints and arbitrary references. Starting from partial differential equations to model heat propagation over the geometry, prediction models and optimization problems are formulated as a local part of a more detailed simulation model of the complete workpiece. For laser velocity and power as manipulated variables, optimization problems involving integer variables are solved. Simulation results show how spatial temperature profiles can be adjusted by the proposed approach.},
  author = {Schmidtke, V. and Rüger, M. and Stursberg, O.},
  journal = {Proc. of the 2023 European Control Conference},
  keywords = {isac-www},
  pages = {496-501},
  title = {Model Predictive Control of PDEs for Temperature Control in 3D-Printing Processes.},
  year = 2023