针对仿人机器人运动姿态和行为的离散轨迹规划中所存在的机器人稳定性问题,提出了基于压应力中心反馈的控制方法.该方法以17自由度的仿人机器人MechG作为样机,根据动态平衡状态下机器人的压应力中心(Center of Pressure,COP)和零力矩点(...针对仿人机器人运动姿态和行为的离散轨迹规划中所存在的机器人稳定性问题,提出了基于压应力中心反馈的控制方法.该方法以17自由度的仿人机器人MechG作为样机,根据动态平衡状态下机器人的压应力中心(Center of Pressure,COP)和零力矩点(Zero Moment Point,ZMP)重合的特性,通过检测COP反馈信息实时调整仿人机器人的各关节运动速度,以此规避机器人的不稳定轨迹点.通过机器人MechG的实验,验证了所提出的控制方法是可行的.展开更多
Structural integrity procedures were used to demonstrate the fitness for the purpose of engineering components transmitting loads. The prediction of the fracture strength of titanium alloys containing sharp notches th...Structural integrity procedures were used to demonstrate the fitness for the purpose of engineering components transmitting loads. The prediction of the fracture strength of titanium alloys containing sharp notches through the damage model depends on the un-notched strength and the critical length of the damage zone ahead of the notch. In general, the critical length of the damage zone depends on the material, specimen, and size of the sharp notch. Modifications were made in one of the stress fracture criteria known as the average stress criterion for accurate prediction of notched tensile strength of titanium alloy specimen containing sharp notches. To examine the adequacy of these modifications, fracture data of center-cracked titanium alloys with various thicknesses are considered. The notched （fracture） strength estimates are found to be close to the test results. The modified average stress criterion is very simple to predict the notched tensile strength.展开更多
In this paper stresses at joints forming by hollow steel tube and concrete filled steel tube （CFST） are calculated, analyzed and compared. It is founded that the stress concentration at joints of CFST is a quite dif...In this paper stresses at joints forming by hollow steel tube and concrete filled steel tube （CFST） are calculated, analyzed and compared. It is founded that the stress concentration at joints of CFST is a quite different from that of hollow steel tube. A conclusion can be made that analysis of fatigue at the joints of CFST truss arch bridge can not apply the results developed from analyzing at joints of hollow steel tube in marine structure.展开更多
The distribution of vertical stress for both active and passive state in the silo with a central innerdowncomer is reported in this paper. Experimental measurement of the axial distribution of vertical stress for both...The distribution of vertical stress for both active and passive state in the silo with a central innerdowncomer is reported in this paper. Experimental measurement of the axial distribution of vertical stress for bothactive and passive state in the silo are in good agreement with that predicted by theoretical analysis. The meanaxial stress is reduced due to the presence of the inner downcomer in the silo.展开更多
文摘针对仿人机器人运动姿态和行为的离散轨迹规划中所存在的机器人稳定性问题,提出了基于压应力中心反馈的控制方法.该方法以17自由度的仿人机器人MechG作为样机,根据动态平衡状态下机器人的压应力中心(Center of Pressure,COP)和零力矩点(Zero Moment Point,ZMP)重合的特性,通过检测COP反馈信息实时调整仿人机器人的各关节运动速度,以此规避机器人的不稳定轨迹点.通过机器人MechG的实验,验证了所提出的控制方法是可行的.
文摘Structural integrity procedures were used to demonstrate the fitness for the purpose of engineering components transmitting loads. The prediction of the fracture strength of titanium alloys containing sharp notches through the damage model depends on the un-notched strength and the critical length of the damage zone ahead of the notch. In general, the critical length of the damage zone depends on the material, specimen, and size of the sharp notch. Modifications were made in one of the stress fracture criteria known as the average stress criterion for accurate prediction of notched tensile strength of titanium alloy specimen containing sharp notches. To examine the adequacy of these modifications, fracture data of center-cracked titanium alloys with various thicknesses are considered. The notched （fracture） strength estimates are found to be close to the test results. The modified average stress criterion is very simple to predict the notched tensile strength.
文摘In this paper stresses at joints forming by hollow steel tube and concrete filled steel tube （CFST） are calculated, analyzed and compared. It is founded that the stress concentration at joints of CFST is a quite different from that of hollow steel tube. A conclusion can be made that analysis of fatigue at the joints of CFST truss arch bridge can not apply the results developed from analyzing at joints of hollow steel tube in marine structure.
文摘The distribution of vertical stress for both active and passive state in the silo with a central innerdowncomer is reported in this paper. Experimental measurement of the axial distribution of vertical stress for bothactive and passive state in the silo are in good agreement with that predicted by theoretical analysis. The meanaxial stress is reduced due to the presence of the inner downcomer in the silo.
