Pub Date : 2020-07-01DOI: 10.23919/ACC45564.2020.9147655
K. Prochazka, G. Stomberg
This paper presents a novel concept for active fault-tolerant control (FTC) of dual system hybrid unmanned aerial vehicles (UAVs) based on analytical redundancy to increase the operational safety in the face of primary actuator faults. The proposed scheme exploits the inherent overactuation property of hybrid UAVs when in addition to the aerodynamic surfaces four lift rotors are used to control the aircraft during long range fixed-wing flight mode. Fault tolerance is achieved by utilizing an integral sliding mode based model reference control law combined with control allocation techniques to reallocate control signals among healthy effectors in the face of actuator faults and maintain nominal closedloop performance. After introducing the modelling procedure of the UAV, including the identification of aerodynamical cross-couplings between lift rotors and airframe dynamics, Hardware-in-the-loop (HIL) simulation results are presented to demonstrate the efficiency of the proposed scheme in a realistic hardware setup.
{"title":"Integral Sliding Mode based Model Reference FTC of an Over-Actuated Hybrid UAV using Online Control Allocation","authors":"K. Prochazka, G. Stomberg","doi":"10.23919/ACC45564.2020.9147655","DOIUrl":"https://doi.org/10.23919/ACC45564.2020.9147655","url":null,"abstract":"This paper presents a novel concept for active fault-tolerant control (FTC) of dual system hybrid unmanned aerial vehicles (UAVs) based on analytical redundancy to increase the operational safety in the face of primary actuator faults. The proposed scheme exploits the inherent overactuation property of hybrid UAVs when in addition to the aerodynamic surfaces four lift rotors are used to control the aircraft during long range fixed-wing flight mode. Fault tolerance is achieved by utilizing an integral sliding mode based model reference control law combined with control allocation techniques to reallocate control signals among healthy effectors in the face of actuator faults and maintain nominal closedloop performance. After introducing the modelling procedure of the UAV, including the identification of aerodynamical cross-couplings between lift rotors and airframe dynamics, Hardware-in-the-loop (HIL) simulation results are presented to demonstrate the efficiency of the proposed scheme in a realistic hardware setup.","PeriodicalId":288450,"journal":{"name":"2020 American Control Conference (ACC)","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116591628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/ACC45564.2020.9148042
Tianyi He, G. Zhu, Xiang Chen
In this paper, a two-step H2 − H∞ control design scheme with guaranteed mixed H2 and H∞ performance is proposed. Different from the traditional H2/H∞ control, the proposed method designs an H2 controller for a nominal plant and then designs an extra Q operator to recover robustness in H∞ sense for the closed-loop system. When the system uncertainty occurs, operator Q is triggered by a residual signal due to the error between the nominal model and the actual plants, and an extra control signal is generated by operator Q to compensate the nominal H2 controller. It is noted that the proposed H2 − H∞ design scheme provides additional design freedom to reduce conservativeness, comparing with the traditional mixed H2/H∞ control. The control design in the Linear Matrix Inequality (LMI) approach is applied to synthesize the H2 − H∞ controller. Simulation results of a numerical example are given to demonstrate that H2 − H∞ control design is able to compensate the nominal H2 control and significantly improve system performance in the presence of system uncertainty. Moreover, two-step H2 −H∞ control renders better state responses than the traditional mixed H2/H∞ control.
{"title":"A Two-step LMI Scheme for H2 − H∞ Control Design","authors":"Tianyi He, G. Zhu, Xiang Chen","doi":"10.23919/ACC45564.2020.9148042","DOIUrl":"https://doi.org/10.23919/ACC45564.2020.9148042","url":null,"abstract":"In this paper, a two-step H<inf>2</inf> − H<inf>∞</inf> control design scheme with guaranteed mixed H<inf>2</inf> and H<inf>∞</inf> performance is proposed. Different from the traditional H<inf>2</inf>/H<inf>∞</inf> control, the proposed method designs an H<inf>2</inf> controller for a nominal plant and then designs an extra Q operator to recover robustness in H<inf>∞</inf> sense for the closed-loop system. When the system uncertainty occurs, operator Q is triggered by a residual signal due to the error between the nominal model and the actual plants, and an extra control signal is generated by operator Q to compensate the nominal H<inf>2</inf> controller. It is noted that the proposed H<inf>2</inf> − H<inf>∞</inf> design scheme provides additional design freedom to reduce conservativeness, comparing with the traditional mixed H<inf>2</inf>/H<inf>∞</inf> control. The control design in the Linear Matrix Inequality (LMI) approach is applied to synthesize the H<inf>2</inf> − H<inf>∞</inf> controller. Simulation results of a numerical example are given to demonstrate that H<inf>2</inf> − H<inf>∞</inf> control design is able to compensate the nominal H<inf>2</inf> control and significantly improve system performance in the presence of system uncertainty. Moreover, two-step H<inf>2</inf> −H<inf>∞</inf> control renders better state responses than the traditional mixed H<inf>2</inf>/H<inf>∞</inf> control.","PeriodicalId":288450,"journal":{"name":"2020 American Control Conference (ACC)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116851218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/ACC45564.2020.9147793
S. Ifqir, D. Ichalal, N. A. Oufroukh, S. Mammar
Lateral velocity and tire-road forces are vital signals that affect the stability of a vehicle under cornering. Unfortunately, for both technical and economic reasons, these fundamental vehicle parameters can hardly be measured directly through sensors. As a consequence, an efficient and reliable algorithm for estimating vehicle lateral velocity and tire-road forces is needed. This paper presents a novel framework for estimation of vehicle lateral velocity and lateral tire-road forces. The proposed algorithm is based on switched interval observers and is able to cope with changes of tire operating conditions. The interval estimation algorithm is evaluated through experimental data acquired using an instrumented vehicle. Simulation results show that the developed system can reliably estimate the upper and lower bounds of vehicle lateral variables during both steady and transient maneuvers.
{"title":"Vehicle Lateral Velocity and Lateral Tire-road Forces Estimation Based on Switched Interval Observers","authors":"S. Ifqir, D. Ichalal, N. A. Oufroukh, S. Mammar","doi":"10.23919/ACC45564.2020.9147793","DOIUrl":"https://doi.org/10.23919/ACC45564.2020.9147793","url":null,"abstract":"Lateral velocity and tire-road forces are vital signals that affect the stability of a vehicle under cornering. Unfortunately, for both technical and economic reasons, these fundamental vehicle parameters can hardly be measured directly through sensors. As a consequence, an efficient and reliable algorithm for estimating vehicle lateral velocity and tire-road forces is needed. This paper presents a novel framework for estimation of vehicle lateral velocity and lateral tire-road forces. The proposed algorithm is based on switched interval observers and is able to cope with changes of tire operating conditions. The interval estimation algorithm is evaluated through experimental data acquired using an instrumented vehicle. Simulation results show that the developed system can reliably estimate the upper and lower bounds of vehicle lateral variables during both steady and transient maneuvers.","PeriodicalId":288450,"journal":{"name":"2020 American Control Conference (ACC)","volume":"805 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117045614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/ACC45564.2020.9147800
Felix Goßmann, Agnes Gabrys, F. Svaricek
In this paper, an LPV longitudinal flight controller design is presented, which takes variations of mass and mass distribution into account without the need for additional measurements or estimation of the current loadcase (a certain combination of mass, center of gravity and inertia tensor). This means the loadcase variation is included in the LPV model, but the obtained controller depends on the measurable variations of altitude and airspeed only. Therefore, a technique based on LPV systems with partly-measurable parameters is used. This approach is applied to the control of the short-period dynamic on a model of a small regional aircraft. The obtained controller is evaluated on a more detailed linear model, which takes parts of the real control system into account, as well as within a 6DOF high-fidelity nonlinear simulation environment, which is used to analyze flight controllers before real-life flight tests.
{"title":"Longitudinal Short-Period Aircraft Motion Control Under Loadcase Variation","authors":"Felix Goßmann, Agnes Gabrys, F. Svaricek","doi":"10.23919/ACC45564.2020.9147800","DOIUrl":"https://doi.org/10.23919/ACC45564.2020.9147800","url":null,"abstract":"In this paper, an LPV longitudinal flight controller design is presented, which takes variations of mass and mass distribution into account without the need for additional measurements or estimation of the current loadcase (a certain combination of mass, center of gravity and inertia tensor). This means the loadcase variation is included in the LPV model, but the obtained controller depends on the measurable variations of altitude and airspeed only. Therefore, a technique based on LPV systems with partly-measurable parameters is used. This approach is applied to the control of the short-period dynamic on a model of a small regional aircraft. The obtained controller is evaluated on a more detailed linear model, which takes parts of the real control system into account, as well as within a 6DOF high-fidelity nonlinear simulation environment, which is used to analyze flight controllers before real-life flight tests.","PeriodicalId":288450,"journal":{"name":"2020 American Control Conference (ACC)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117299781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/ACC45564.2020.9147708
Thomas L. Dearing, C. Petersen, M. Nicotra, Xudong Chen
We consider a continuous-time optimal control problem for a swarm of single thruster, single reaction wheel spacecraft aiming to reach a target formation. The dynamic model of each spacecraft is obtained by augmenting the Hill-Clohessy-Wiltshire equations with the coupled dynamics of the reaction wheel and thruster. For the optimal control problem, we penalize the deviation from the target formation, the overall fuel usage, and the fuel imbalance between agents. The optimal control law is then obtained by using the minimum principle to formulate a split-boundary-value ODE, which is then solved numerically. Numerical simulations for a simple swarm of three satellites show that the proposed approach successfully reduces the fuel consumption of the most fuel-intensive spacecraft, thus extending the overall lifetime of the formation system.
{"title":"Fuel-Balanced Formation Flight Control of Underactuated Satellites","authors":"Thomas L. Dearing, C. Petersen, M. Nicotra, Xudong Chen","doi":"10.23919/ACC45564.2020.9147708","DOIUrl":"https://doi.org/10.23919/ACC45564.2020.9147708","url":null,"abstract":"We consider a continuous-time optimal control problem for a swarm of single thruster, single reaction wheel spacecraft aiming to reach a target formation. The dynamic model of each spacecraft is obtained by augmenting the Hill-Clohessy-Wiltshire equations with the coupled dynamics of the reaction wheel and thruster. For the optimal control problem, we penalize the deviation from the target formation, the overall fuel usage, and the fuel imbalance between agents. The optimal control law is then obtained by using the minimum principle to formulate a split-boundary-value ODE, which is then solved numerically. Numerical simulations for a simple swarm of three satellites show that the proposed approach successfully reduces the fuel consumption of the most fuel-intensive spacecraft, thus extending the overall lifetime of the formation system.","PeriodicalId":288450,"journal":{"name":"2020 American Control Conference (ACC)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128398258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/ACC45564.2020.9147672
A. Mark, Yun-Hong Xu, Benjamin T. Dickinson
Control allocation is required in many networked systems or systems with distributed actuating subsystems for the purpose of achieving hardware redundancy or increasing actuation efficiency. As the number of actuators increases, the computational cost also increases and the robustness with respect to real-time information sacrifices if a typical centralized, open-loop optimization method is used for control allocation. This study proposes a new consensus based distributed allocation scheme for actuators/jets onboard a conceptual small unmanned aerial system. Different from our previous research, the distributed actuators are connected via a directed/undirected graph. The proposed method is validated via simulation.
{"title":"Control Allocation Consensus among onboard Actuators with a Directed/Undirected Graph Topology","authors":"A. Mark, Yun-Hong Xu, Benjamin T. Dickinson","doi":"10.23919/ACC45564.2020.9147672","DOIUrl":"https://doi.org/10.23919/ACC45564.2020.9147672","url":null,"abstract":"Control allocation is required in many networked systems or systems with distributed actuating subsystems for the purpose of achieving hardware redundancy or increasing actuation efficiency. As the number of actuators increases, the computational cost also increases and the robustness with respect to real-time information sacrifices if a typical centralized, open-loop optimization method is used for control allocation. This study proposes a new consensus based distributed allocation scheme for actuators/jets onboard a conceptual small unmanned aerial system. Different from our previous research, the distributed actuators are connected via a directed/undirected graph. The proposed method is validated via simulation.","PeriodicalId":288450,"journal":{"name":"2020 American Control Conference (ACC)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128237386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/ACC45564.2020.9147385
Yi Zhang, R. Su, Yicheng Zhang
We present a platoon-based bus dispatching strategy and passenger boarding strategy which utilizes a platoon of vehicles to improve capacity flexibility in response to dynamically changing demands, and controls passenger boarding flows to minimize the networkwise passengers’ perceived delay time. The released buses in the same platoon are allowed to separate when approaching the stop station, which makes our strategy more flexible and data-driven. A Mixed Integer Linear Programming (MILP) model is firstly developed to formulate the problem with the linear cost, in which both the passengers’ actual delay time and the operating bus vacancy are minimized subject to the volume dynamic constraints on both buses and stops. With the computational complexity as a concern, the Genetic Algorithm (GA) is adopted to solve the problem in real time. Comparison between MILP and GA on the computational time and result quality is conducted to show the efficiency of our method. Also, the optimization model with the nonlinear cost considering the passengers’ perceived delay time and the operating bus vacancy is directly solved by the GA. Finally, the performance of our method and the traditional bus schedule strategies under two different objectives is discussed in the case study, which indicates the potential of the platoon dispatching in mitigating the passenger’s perceived delay.
{"title":"A dynamic optimization model for bus schedule design to mitigate the passenger waiting time by dispatching the bus platoon","authors":"Yi Zhang, R. Su, Yicheng Zhang","doi":"10.23919/ACC45564.2020.9147385","DOIUrl":"https://doi.org/10.23919/ACC45564.2020.9147385","url":null,"abstract":"We present a platoon-based bus dispatching strategy and passenger boarding strategy which utilizes a platoon of vehicles to improve capacity flexibility in response to dynamically changing demands, and controls passenger boarding flows to minimize the networkwise passengers’ perceived delay time. The released buses in the same platoon are allowed to separate when approaching the stop station, which makes our strategy more flexible and data-driven. A Mixed Integer Linear Programming (MILP) model is firstly developed to formulate the problem with the linear cost, in which both the passengers’ actual delay time and the operating bus vacancy are minimized subject to the volume dynamic constraints on both buses and stops. With the computational complexity as a concern, the Genetic Algorithm (GA) is adopted to solve the problem in real time. Comparison between MILP and GA on the computational time and result quality is conducted to show the efficiency of our method. Also, the optimization model with the nonlinear cost considering the passengers’ perceived delay time and the operating bus vacancy is directly solved by the GA. Finally, the performance of our method and the traditional bus schedule strategies under two different objectives is discussed in the case study, which indicates the potential of the platoon dispatching in mitigating the passenger’s perceived delay.","PeriodicalId":288450,"journal":{"name":"2020 American Control Conference (ACC)","volume":"1999 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128254162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/ACC45564.2020.9147969
Paul Ghanem, A. Wolek, D. Paley
This paper presents a nonlinear control design for the stabilization of parallel and circular motion in a model school of robotic fish. The closed-loop swimming dynamics of the fish robots are represented by the canonical Chaplygin sleigh—a nonholonomic mechanical system driven by an internal rotor. The fish robots exchange relative state information according to a connected, undirected communication graph and form a system of coupled, nonlinear, second-order oscillators. Prior work on collective motion of constant-speed, self-propelled particles serves as the foundation of our approach. However, unlike the self-propelled particle, the fish robots follow limit-cycle dynamics to sustain periodic flapping for forward motion with a varying speed. Parallel and circular motions are achieved in an average sense. The proposed control laws do not include feedback linearization of the agents’ dynamics. Numerical simulations illustrate the approach.
{"title":"Planar Formation Control of a School of Robotic Fish","authors":"Paul Ghanem, A. Wolek, D. Paley","doi":"10.23919/ACC45564.2020.9147969","DOIUrl":"https://doi.org/10.23919/ACC45564.2020.9147969","url":null,"abstract":"This paper presents a nonlinear control design for the stabilization of parallel and circular motion in a model school of robotic fish. The closed-loop swimming dynamics of the fish robots are represented by the canonical Chaplygin sleigh—a nonholonomic mechanical system driven by an internal rotor. The fish robots exchange relative state information according to a connected, undirected communication graph and form a system of coupled, nonlinear, second-order oscillators. Prior work on collective motion of constant-speed, self-propelled particles serves as the foundation of our approach. However, unlike the self-propelled particle, the fish robots follow limit-cycle dynamics to sustain periodic flapping for forward motion with a varying speed. Parallel and circular motions are achieved in an average sense. The proposed control laws do not include feedback linearization of the agents’ dynamics. Numerical simulations illustrate the approach.","PeriodicalId":288450,"journal":{"name":"2020 American Control Conference (ACC)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128975224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/ACC45564.2020.9147497
Yalun Wen, P. Pagilla
In this paper we describe a novel path following scheme for robot end-effectors that is particularly suitable for robotic surface finishing operations where constant velocity of travel on the surface is desirable. The scheme is applicable to general situations where the path is typically given in terms of measured data from a sensor, and also to paths that are specified in terms of analytical curves (circular or ellipsoidal). Considering the given data points as control points, we utilize cubic spline interpolation to generate a closed-form geometric description for the path. Since velocity control is quite common in many industrial robots and most surface finishing tasks require travel with constant velocity along the path, we consider a kinematic model for the end-effector with control inputs as rate of change of orientation and translational velocity. By utilizing a path variable and the tangent vector along the path, we describe the complete path as the path that is taken from the initial robot end-effector point to the desired path and subsequent travel on the desired path. To evaluate the performance of the scheme, we have conducted a number of real-time experiments on an industrial robot for circular paths and for paths generated for gear deburring and chamfering, and results from those experiments will be discussed.
{"title":"A Novel Path Following Scheme for Robot End-Effectors","authors":"Yalun Wen, P. Pagilla","doi":"10.23919/ACC45564.2020.9147497","DOIUrl":"https://doi.org/10.23919/ACC45564.2020.9147497","url":null,"abstract":"In this paper we describe a novel path following scheme for robot end-effectors that is particularly suitable for robotic surface finishing operations where constant velocity of travel on the surface is desirable. The scheme is applicable to general situations where the path is typically given in terms of measured data from a sensor, and also to paths that are specified in terms of analytical curves (circular or ellipsoidal). Considering the given data points as control points, we utilize cubic spline interpolation to generate a closed-form geometric description for the path. Since velocity control is quite common in many industrial robots and most surface finishing tasks require travel with constant velocity along the path, we consider a kinematic model for the end-effector with control inputs as rate of change of orientation and translational velocity. By utilizing a path variable and the tangent vector along the path, we describe the complete path as the path that is taken from the initial robot end-effector point to the desired path and subsequent travel on the desired path. To evaluate the performance of the scheme, we have conducted a number of real-time experiments on an industrial robot for circular paths and for paths generated for gear deburring and chamfering, and results from those experiments will be discussed.","PeriodicalId":288450,"journal":{"name":"2020 American Control Conference (ACC)","volume":"60 16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129252852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/ACC45564.2020.9147559
A. Cervin, M. Andren
In this paper, we study event-based PID control from an optimal stochastic control perspective. The purpose is to better understand what implementation features are critical for achieving good event-based PID performance. For this end, we formulate an LQG control design problem for a double integrator process with an integral disturbance, where the solution is an ideal PID controller. We then consider the tradeoff between LQG cost and average sampling rate and give an interpretation of the optimal sampled-data controller and event- based sampling policy in terms of PID control. Based on insights from the optimal solution, we finally discuss how suboptimal but simple event-based PID controllers can be implemented. The proposed implementation is evaluated in a simulation study and compared to earlier work in event-based PID control. The results highlight the importance of considering both the triggering rule and the transmitted information in order to obtain an event-based PID controller with good performance.
{"title":"LQG-Optimal versus Simple Event-Based PID Controllers","authors":"A. Cervin, M. Andren","doi":"10.23919/ACC45564.2020.9147559","DOIUrl":"https://doi.org/10.23919/ACC45564.2020.9147559","url":null,"abstract":"In this paper, we study event-based PID control from an optimal stochastic control perspective. The purpose is to better understand what implementation features are critical for achieving good event-based PID performance. For this end, we formulate an LQG control design problem for a double integrator process with an integral disturbance, where the solution is an ideal PID controller. We then consider the tradeoff between LQG cost and average sampling rate and give an interpretation of the optimal sampled-data controller and event- based sampling policy in terms of PID control. Based on insights from the optimal solution, we finally discuss how suboptimal but simple event-based PID controllers can be implemented. The proposed implementation is evaluated in a simulation study and compared to earlier work in event-based PID control. The results highlight the importance of considering both the triggering rule and the transmitted information in order to obtain an event-based PID controller with good performance.","PeriodicalId":288450,"journal":{"name":"2020 American Control Conference (ACC)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124560153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}