Abstract: Disclosed is an active control Stewart vibration damping platform, including a load-bearing platform, a base, and six telescopic rods. Each telescopic rod includes a driving motor, a rotating shaft, a sleeve, and a moving rod. One end, away from the driving motor, of the rotating shaft is provided with a cylindrical cavity, one end of the moving rod penetrates through the cylindrical cavity, and the sleeve is sleeved outside the rotating shaft. The rotating shaft is in running fit with the sleeve through a first bearing, and the moving rod is in sliding fit with the sleeve through a second bearing. The moving rod and the rotating shaft are respectively provided with a spiral permanent magnet. The spiral permanent magnet on the rotating shaft can drive the moving rod to move in an axial direction of the rotating shaft through the spiral permanent magnet on the moving rod when rotating.

Abstract: A horizontally arranged six-degree-of-freedom constant-stiffness mechanism is provided, and includes an upper platform, a bottom plate, three composite spherical hinges, spherical hinges, support rods, guide rail slider assemblies, and six electromagnetic adjustable stiffness units. Two ends of a shaft on which a permanent magnet is fixed in each electromagnetic adjustable stiffness unit are fixed to the bottom plate via shaft supports. Axially moving housings of electromagnetic adjustable stiffness units are fixed on sliders of the guide rail slider assemblies via slider backing plates respectively. Guide rail slider assembles are fixed on the bottom plate. Tops of the housings are mounted with the spherical hinges respectively. A bottom of the upper platform is uniformly mounted with the composite spherical hinges. One end of each support rod is threadedly connected to a corresponding one of the spherical hinges, and another end is connected with a corresponding one of composite spherical hinges.

Abstract: Disclosed is an active control Stewart vibration damping platform, including a load-bearing platform, a base, and six telescopic rods. Each telescopic rod includes a driving motor, a rotating shall, a sleeve, and a moving rod. One end, away from the driving motor, of the rotating shaft is provided with a cylindrical cavity, one end of the moving rod penetrates through the cylindrical cavity, and the sleeve is sleeved outside the rotating shall. The rotating shaft is in running lit with the sleeve through a first bearing, and the moving rod is in sliding fit with the sleeve through a second bearing. The moving rod and the rotating shaft are respectively provided with a spiral permanent magnet. The spiral permanent magnet on the rotating shaft can drive the moving rod to move in an axial direction of the rotating shaft through the spiral permanent magnet on the moving rod when rotating.

Abstract: A magnetic suspension type sensing system for space full-degree-of-freedom absolute poses is provided. The system includes a reference platform, multiple quasi-zero stiffness supporting legs and a platform to be tested. The reference platform and the platform to be tested are connected in a spherical hinge mode through the multiple quasi-zero stiffness supporting legs. Each of the multiple quasi-zero stiffness supporting legs includes a lower end spherical hinge, a lower end cover, a positive stiffness unit, a negative stiffness unit, a shaft, a lower end shell, an upper end shell and an upper end spherical hinge.

Abstract: A negative stiffness generating mechanism and a quasi-zero stiffness vibration isolator are provided. A housing is mounted on a base, and the axial relative positions of the housing and the base can be adjusted; a negative stiffness unit comprises inner-ring magnets, outer-ring magnets and a supporting shaft, the supporting shaft axially slides on the base and passes through the housing, the inner-ring magnets fixedly sleeve the supporting shaft, and the outer-ring magnets sleeve outside the inner-ring magnets and are divided into upper and lower groups of outer-ring magnets; the upper and lower groups of outer-ring magnets can synchronously move through a negative stiffness adjusting device; and the axial relative positions of the middle planes of the outer-ring and inner-ring magnets can be adjusted by adjusting the axial relative positions of the housing and the base. The isolator comprises a negative stiffness generating mechanism and a positive stiffness unit.

Abstract: A magnetic suspension type sensing system for space full-degree-of-freedom absolute poses is provided. The system includes a reference platform, multiple quasi-zero stiffness supporting legs and a platform to be tested. The reference platform and the platform to be tested are connected in a spherical hinge mode through the multiple quasi-zero stiffness supporting legs. Each of the multiple quasi-zero stiffness supporting legs includes a lower end spherical hinge, a lower end cover, a positive stiffness unit, a negative stiffness unit, a shaft, a lower end shell, an upper end shell and an upper end spherical hinge.

Abstract: Disclosed is a quasi-zero stiffness absolute displacement sensor based on electromagnetic positive stiffness, and relates to the technical field of vibration measurement. The quasi-zero stiffness absolute displacement sensor comprises an eddy current displacement sensor unit, a negative stiffness unit, an intermediate connector, a positive stiffness unit, a bottom shell and a motion axis. The damping of the mechanism can be effectively reduced, the service life of the system is prolonged, and the mechanism size is reduced. By adjusting the number of layers of permanent magnets and coils in the electromagnetic positive stiffness unit and the electromagnetic negative stiffness unit and controlling the magnitude of current in the coils, electromagnetic force between the permanent magnets and the electromagnetic coils can be changed, the magnitude of positive stiffness and the magnitude of negative stiffness are adjusted, and control over the stiffness of the whole system is achieved.

Abstract: Disclosed is a quasi-zero stiffness absolute displacement sensor based on electromagnetic positive stiffness, and relates to the technical field of vibration measurement. The quasi-zero stiffness absolute displacement sensor comprises an eddy current displacement sensor unit, a negative stiffness unit, an intermediate connector, a positive stiffness unit, a bottom shell and a motion axis. The damping of the mechanism can be effectively reduced, the service life of the system is prolonged, and the mechanism size is reduced. By adjusting the number of layers of permanent magnets and coils in the electromagnetic positive stiffness unit and the electromagnetic negative stiffness unit and controlling the magnitude of current in the coils, electromagnetic force between the permanent magnets and the electromagnetic coils can be changed, the magnitude of positive stiffness and the magnitude of negative stiffness are adjusted, and control over the stiffness of the whole system is achieved.

Abstract: A horizontally arranged six-degree-of-freedom constant-stiffness mechanism is provided, and includes an upper platform, a bottom plate, three composite spherical hinges, spherical hinges, support rods, guide rail slider assemblies, and six electromagnetic adjustable stiffness units. Two ends of a shaft on which a permanent magnet is fixed in each electromagnetic adjustable stiffness unit are fixed to the bottom plate via shaft supports. Axially moving housings of electromagnetic adjustable stiffness units are fixed on sliders of the guide rail slider assemblies via slider backing plates respectively. Guide rail slider assembles are fixed on the bottom plate. Tops of the housings are mounted with the spherical hinges respectively. A bottom of the upper platform is uniformly mounted with the composite spherical hinges. One end of each support rod is threadedly connected to a corresponding one of the spherical hinges, and another end is connected with a corresponding one of composite spherical hinges.

Abstract: The present invention discloses a quasi-zero-stiffness (QZS) based six-degree-of-freedom (6-DOF) absolute displacement and attitude measurement device. A lower end coil and an upper end coil are respectively charged with currents in the opposite directions; The electromagnetic field and the magnetic fields of an upper magnet and a lower magnet per se are mutually acted to produce an electromagnetic stiffness opposite to the stiffness of a spring. The stiffness of the whole leg is close to zero stiffness. When the to-be-measured platform generates space motion, the reference platform is in the stationary state. At this point, the deformation amounts of the six legs can be measured by laser displacement sensors. The six deformation amounts are respectively inputted into the displacement and attitude resolver, and by forward kinematic solution of the 6-DOF device, the displacement and the attitude of the to-be-measured platform can be obtained.

Abstract: An electromagnetic type quasi-zero stiffness absolute displacement sensor that includes an intermediate shaft, upper end cover, first sliding bearing arranged on the upper end cover, upper housing fixedly connected to the upper end cover, electromagnetic coil fastened onto an inner wall of the upper housing, spiral spring, spring support connected to a lower end of the spiral spring, force sensor fastened onto a lower end surface of the spring support, lower end cover fastened onto lower end surface of the force sensor, and a lower housing connected to the lower end cover; the intermediate shaft sequentially passes through, from top down, the first sliding bearing, upper end cover, and electromagnetic coil, and is connected to an upper end of the spiral spring; and the upper housing is provided therein with a ring permanent magnet that is nested on the intermediate shaft and is not in contact with the electromagnetic coil.

Abstract: An electromagnetic type quasi-zero stiffness absolute displacement sensor that includes an intermediate shaft, upper end cover, first sliding bearing arranged on the upper end cover, upper housing fixedly connected to the upper end cover, electromagnetic coil fastened onto an inner wall of the upper housing, spiral spring, spring support connected to a lower end of the spiral spring, force sensor fastened onto a lower end surface of the spring support, lower end cover fastened onto lower end surface of the force sensor, and a lower housing connected to the lower end cover; the intermediate shaft sequentially passes through, from top down, the first sliding bearing, upper end cover, and electromagnetic coil, and is connected to an upper end of the spiral spring; and the upper housing is provided therein with a ring permanent magnet that is nested on the intermediate shaft and is not in contact with the electromagnetic coil.