电动助力转向系统(Electric Power Steering,EPS)必须随时根据驾驶员的操作,提供渐进随动的转向助力动作,所以系统必须有很高的跟踪性和很好的稳定性.在对EPS的工作原理和力学模型分析的基础上,建立EPS系统仿真模型,设计出一种模糊自适...电动助力转向系统(Electric Power Steering,EPS)必须随时根据驾驶员的操作,提供渐进随动的转向助力动作,所以系统必须有很高的跟踪性和很好的稳定性.在对EPS的工作原理和力学模型分析的基础上,建立EPS系统仿真模型,设计出一种模糊自适应PID(Proportion-Integral-Derivative)控制器,有效地改善了传统PID控制器的不足.通过仿真表明,这种模糊自适应PID控制器与传统PID控制器相比,具有更好的跟踪性和稳定性.展开更多
Several algorithms were proposed relating to the development of a framework of the perturbation-based stochastic finite element method (PSFEM) for large variation nonlinear dynamic problems. For this purpose, algorith...Several algorithms were proposed relating to the development of a framework of the perturbation-based stochastic finite element method (PSFEM) for large variation nonlinear dynamic problems. For this purpose, algorithms and a framework related to SFEM based on the stochastic virtual work principle were studied. To prove the validity and practicality of the algorithms and framework, numerical examples for nonlinear dynamic problems with large variations were calculated and compared with the Monte-Carlo Simulation method. This comparison shows that the proposed approaches are accurate and effective for the nonlinear dynamic analysis of structures with random parameters.展开更多
Based on the dynamic triaxial test system and using the fitted wave of the Wenchuan earthquake and 1 Hz constant amplitude sinusoid,the paper compares the results of tests on undisturbed loess samples under different ...Based on the dynamic triaxial test system and using the fitted wave of the Wenchuan earthquake and 1 Hz constant amplitude sinusoid,the paper compares the results of tests on undisturbed loess samples under different loads and vibration modes but under same saturated conditions.Results of the comparative experiment show:The stress-strain curves have a similar trend under random seismic loading and constant amplitude sinusoidal loading,but the random seismic loading is more sensitive to failure strength of the undisturbed loess samples under the same stress.展开更多
文摘电动助力转向系统(Electric Power Steering,EPS)必须随时根据驾驶员的操作,提供渐进随动的转向助力动作,所以系统必须有很高的跟踪性和很好的稳定性.在对EPS的工作原理和力学模型分析的基础上,建立EPS系统仿真模型,设计出一种模糊自适应PID(Proportion-Integral-Derivative)控制器,有效地改善了传统PID控制器的不足.通过仿真表明,这种模糊自适应PID控制器与传统PID控制器相比,具有更好的跟踪性和稳定性.
文摘Several algorithms were proposed relating to the development of a framework of the perturbation-based stochastic finite element method (PSFEM) for large variation nonlinear dynamic problems. For this purpose, algorithms and a framework related to SFEM based on the stochastic virtual work principle were studied. To prove the validity and practicality of the algorithms and framework, numerical examples for nonlinear dynamic problems with large variations were calculated and compared with the Monte-Carlo Simulation method. This comparison shows that the proposed approaches are accurate and effective for the nonlinear dynamic analysis of structures with random parameters.
基金sponsored by the Earthquake Professional Special Program of China Earthquake Administration (2008419031)
文摘Based on the dynamic triaxial test system and using the fitted wave of the Wenchuan earthquake and 1 Hz constant amplitude sinusoid,the paper compares the results of tests on undisturbed loess samples under different loads and vibration modes but under same saturated conditions.Results of the comparative experiment show:The stress-strain curves have a similar trend under random seismic loading and constant amplitude sinusoidal loading,but the random seismic loading is more sensitive to failure strength of the undisturbed loess samples under the same stress.
