Feasibility analysis of soft constraints for input and output variables is critical for model predictive control(MPC).When encountering the infeasible situation, some way should be found to adjust the constraints to g...Feasibility analysis of soft constraints for input and output variables is critical for model predictive control(MPC).When encountering the infeasible situation, some way should be found to adjust the constraints to guarantee that the optimal control law exists. For MPC integrated with soft sensor, considering the soft constraints for critical variables additionally makes it more complicated and difficult for feasibility analysis and constraint adjustment. Therefore, the main contributions are that a linear programming approach is proposed for feasibility analysis, and the corresponding constraint adjustment method and procedure are given as well. The feasibility analysis gives considerations to the manipulated, secondary and critical variables, and the increment of manipulated variables as well. The feasibility analysis and the constraint adjustment are conducted in the entire control process and guarantee the existence of optimal control. In final, a simulation case confirms the contributions in this paper.展开更多
Snap-through instability-based mechanical metamaterials(SIMMs)with bistability,multistability,negative stiffness,or excellent energy absorption and dissipation performance play an important role in various advanced fu...Snap-through instability-based mechanical metamaterials(SIMMs)with bistability,multistability,negative stiffness,or excellent energy absorption and dissipation performance play an important role in various advanced functional applications.They can serve as energy absorbers,energy dampers,or mechanical memory and logic computing devices,while also providing amplified force output and faster response time in flexible robots,or implementing sensing functions combined with piezoelectric or triboelectric electricity.However,thus far,research on SIMMs that have non-fixed boundary constraints,proactive responsiveness,multi-physical field cross-coupling,and deep information processing capabilities is still facing significant challenges,potentially hindering the development and cross-field comprehensive applications of truly intelligent SIMMs.Our objective is to furnish a concise categorization of SIMMs and offer direction for innovative design and functional implementations.We have emphasized that the non-fixed boundary constraint will expand the design possibilities,while the use of stimulus-responsive materials and 4D printing technology will create novel opportunities for the design of SIMMs.These advancements are expected to achieve innovative mechanical properties and functions.展开更多
In this paper. a method to study the stability of nonholonomic systems withrespect to partial variables is given and several stability theorems of nonholonomicsystems with respect to partial variables are obtained. Mo...In this paper. a method to study the stability of nonholonomic systems withrespect to partial variables is given and several stability theorems of nonholonomicsystems with respect to partial variables are obtained. Moreover, a relationshipbetween the stability of a nonholonomic system with respect to all variables and thatto partial variables is obtained.展开更多
With classical variable mass and relativistic variable mass cases being considered.the relativistic D' Alembert principles of Lagrange form Nielsen form and Appell. form for variable mass controllable mechanical s...With classical variable mass and relativistic variable mass cases being considered.the relativistic D' Alembert principles of Lagrange form Nielsen form and Appell. form for variable mass controllable mechanical system are given the relativistic Chaplygin equation. Nielsen equation and Appell equation .for variable mass controllable mechanical system in quasi-coordinates and generalized- coordinates are obtained, and the equations of motion of relativistic controllable mechanical system for holonomic system and constant mass system are diseussed展开更多
文摘Feasibility analysis of soft constraints for input and output variables is critical for model predictive control(MPC).When encountering the infeasible situation, some way should be found to adjust the constraints to guarantee that the optimal control law exists. For MPC integrated with soft sensor, considering the soft constraints for critical variables additionally makes it more complicated and difficult for feasibility analysis and constraint adjustment. Therefore, the main contributions are that a linear programming approach is proposed for feasibility analysis, and the corresponding constraint adjustment method and procedure are given as well. The feasibility analysis gives considerations to the manipulated, secondary and critical variables, and the increment of manipulated variables as well. The feasibility analysis and the constraint adjustment are conducted in the entire control process and guarantee the existence of optimal control. In final, a simulation case confirms the contributions in this paper.
基金financial support provided by the National Key R&D Program of China(2022YFB3805700)the National Natural Science Foundation of China(Grant Nos.12072094 and 12172106)+1 种基金the open research fund of Suzhou Laboratory(No.SZLAB-1508-2024ZD016)the Self-Planned Task(No.SL20230101)of Songjiang Laboratory,Harbin Institute of Technology。
文摘Snap-through instability-based mechanical metamaterials(SIMMs)with bistability,multistability,negative stiffness,or excellent energy absorption and dissipation performance play an important role in various advanced functional applications.They can serve as energy absorbers,energy dampers,or mechanical memory and logic computing devices,while also providing amplified force output and faster response time in flexible robots,or implementing sensing functions combined with piezoelectric or triboelectric electricity.However,thus far,research on SIMMs that have non-fixed boundary constraints,proactive responsiveness,multi-physical field cross-coupling,and deep information processing capabilities is still facing significant challenges,potentially hindering the development and cross-field comprehensive applications of truly intelligent SIMMs.Our objective is to furnish a concise categorization of SIMMs and offer direction for innovative design and functional implementations.We have emphasized that the non-fixed boundary constraint will expand the design possibilities,while the use of stimulus-responsive materials and 4D printing technology will create novel opportunities for the design of SIMMs.These advancements are expected to achieve innovative mechanical properties and functions.
文摘In this paper. a method to study the stability of nonholonomic systems withrespect to partial variables is given and several stability theorems of nonholonomicsystems with respect to partial variables are obtained. Moreover, a relationshipbetween the stability of a nonholonomic system with respect to all variables and thatto partial variables is obtained.
文摘With classical variable mass and relativistic variable mass cases being considered.the relativistic D' Alembert principles of Lagrange form Nielsen form and Appell. form for variable mass controllable mechanical system are given the relativistic Chaplygin equation. Nielsen equation and Appell equation .for variable mass controllable mechanical system in quasi-coordinates and generalized- coordinates are obtained, and the equations of motion of relativistic controllable mechanical system for holonomic system and constant mass system are diseussed
