Objective To compare the preliminary clinical outcome between fixed platform and rotating high-flexion prosthesis following total knee replacement(TKR).Methods Form January 2007 to December 2009,68 patients with osteo...Objective To compare the preliminary clinical outcome between fixed platform and rotating high-flexion prosthesis following total knee replacement(TKR).Methods Form January 2007 to December 2009,68 patients with osteoarthritis of展开更多
This paper focuses on the type synthesis of two degree-of-freedom(2-DoF) rotational parallel mechanisms(RPMs) that would be applied as mechanisms actuating the inter-satellite link antenna. Based upon Lie group theory...This paper focuses on the type synthesis of two degree-of-freedom(2-DoF) rotational parallel mechanisms(RPMs) that would be applied as mechanisms actuating the inter-satellite link antenna. Based upon Lie group theory, two steps are necessary to synthesize 2-DoF RPMs except describing the continuous desired motions of the moving platform. They are respectively generation of required open-loop limbs between the fixed base and the moving platform and definition of assembly principles for these limbs. Firstly, all available displacement subgroups or submanifolds are obtained readily according to that the continuous motion of the moving platform is the intersection of those of all open-loop limbs. These subgroups or submanifolds are used to generate all the topology structures of limbs. By describing the characteristics of the displacement subgroups and submanifolds intuitively through employing simple geometrical symbols, their intersection and union operations can be carried out easily. Based on this, the assembly principles of two types are defined to synthesize all 2-DoF RPMs using obtained limbs. Finally, two novel categories of 2-DoF RPMs are provided by introducing a circular track and an articulated rotating platform,respectively. This work can lay the foundations for analysis and optimal design of 2-DoF RPMs that actuate the inter-satellite link antenna.展开更多
The high rolling speed of a missile heavily affects the stabilizing capability of the inertial platform in the laser tracking system （LTS） of the missile. In this paper, a rotational stabilizing platform （RSP） and...The high rolling speed of a missile heavily affects the stabilizing capability of the inertial platform in the laser tracking system （LTS） of the missile. In this paper, a rotational stabilizing platform （RSP） and a fuzzy-PID controller is designed to stabilize the inertial platform. This controller integrates the advantages of both fuzzy controller and classic PID controller. A comparison study is carried out to illustrate the advantages of the proposed fuzzy-PID controller over the classic PID controller. Numerical results indicate that the fuzzy-PID controller outperforms the classic one in effectively handling nonlinear disturbances and quickly stabilizing the inertial platform at the sudden change of missile roiling speed.展开更多
文摘Objective To compare the preliminary clinical outcome between fixed platform and rotating high-flexion prosthesis following total knee replacement(TKR).Methods Form January 2007 to December 2009,68 patients with osteoarthritis of
基金supported by the National Natural Science Foundation of China (No. 51475321)Tianjin Research Program of Application Foundation and Advanced Technology (No. 15JCZDJC38900 and No. 16JCYBJC19300)
文摘This paper focuses on the type synthesis of two degree-of-freedom(2-DoF) rotational parallel mechanisms(RPMs) that would be applied as mechanisms actuating the inter-satellite link antenna. Based upon Lie group theory, two steps are necessary to synthesize 2-DoF RPMs except describing the continuous desired motions of the moving platform. They are respectively generation of required open-loop limbs between the fixed base and the moving platform and definition of assembly principles for these limbs. Firstly, all available displacement subgroups or submanifolds are obtained readily according to that the continuous motion of the moving platform is the intersection of those of all open-loop limbs. These subgroups or submanifolds are used to generate all the topology structures of limbs. By describing the characteristics of the displacement subgroups and submanifolds intuitively through employing simple geometrical symbols, their intersection and union operations can be carried out easily. Based on this, the assembly principles of two types are defined to synthesize all 2-DoF RPMs using obtained limbs. Finally, two novel categories of 2-DoF RPMs are provided by introducing a circular track and an articulated rotating platform,respectively. This work can lay the foundations for analysis and optimal design of 2-DoF RPMs that actuate the inter-satellite link antenna.
基金the China Aerospace Science and Innovation Foundation(No. 06CASC0407)
文摘The high rolling speed of a missile heavily affects the stabilizing capability of the inertial platform in the laser tracking system （LTS） of the missile. In this paper, a rotational stabilizing platform （RSP） and a fuzzy-PID controller is designed to stabilize the inertial platform. This controller integrates the advantages of both fuzzy controller and classic PID controller. A comparison study is carried out to illustrate the advantages of the proposed fuzzy-PID controller over the classic PID controller. Numerical results indicate that the fuzzy-PID controller outperforms the classic one in effectively handling nonlinear disturbances and quickly stabilizing the inertial platform at the sudden change of missile roiling speed.
