The present application relates to self-adjusting damping vibration absorbers, in particular to a self-adjusting damping vibration absorber for while-drilling instruments and an adjusting method thereof. The self-adjusting damping vibration absorber includes a vibration monitor and controller tool and a vibration absorber body. The vibration monitor and controller tool is mounted inside the downhole while-drilling instrument, one end of the vibration absorber body is connected to the vibration monitor and controller tool through an insulating connector, the joint is provided with an insulating pad, the other end is connected to a sensor or circuit board tool that needs vibration damping, and the inside of the vibration absorber body is provided with a damping adjustment layer made of an electroactive polymer. By controlling the magnitude of an applied voltage, the damping adjustment can be realized, and the damping adjustment layer has the characteristics of high response speed and high control precision. The self-adjusting damping vibration absorber of the present application can adjust the vibration absorber damping according to the changes of the downhole vibration and temperature, so that the vibration absorber inherent frequency avoids or is far away from the vibration frequency of the downhole while-drilling instrument so as to avoid resonance, and thereby, the vibration absorber achieves the best vibration damping effect.

Apparatus include a reaction mass and an actuator coupled to the reaction mass. The actuator is configured to couple to a payload and to move the reaction mass in response to a movement error of the payload to reduce the movement error of the payload. Robotic systems using actuated reaction masses, as well as related methods of reducing movement errors, are also disclosed.

A force transfer system includes a body and an article. The article includes a first portion forming a first lateral axis and a second portion forming a second lateral axis, the axes being offset. An intermediate member is disposed between the first portion and the second portion, and holds the second portion to the first portion. A stimulus received by the first portion causes a temporary alteration of the intermediate member from an initial condition, the alteration of the intermediate member thereby causing a change in a characteristic of the second portion. The intermediate member subsequently returns to the initial condition, thereby causing a change in a characteristic of the first portion, which is influenced by the change in the characteristic of the second portion. The change in the characteristic of the first and second portions prevents at least a portion of the stimulus from reaching the body.

A vibration control system includes a plurality of spatially distributed transducer elements, a switching circuit, one or more vibration control circuits, and a controller circuit. The switching circuit is connected to each of the transducer elements. The one or more vibration control circuits are configured to perform vibration control, each of the one or more vibration control circuits being connected to the switching circuit. The controller circuit is configured to control the one or more vibration control circuits and the switching circuit. The switching circuit is configured to interconnect selected ones of the transducer elements based on a switching signal provided by the controller circuit, the switching signal being in response to a vibration condition, to adaptively form a group of interconnected transducer elements. The switching circuit is further configured to connect the group of interconnected transducer elements to a selected at least one of the one or more vibration control circuits for receiving a single vibration control signal or electrical impedance source corresponding to the vibration condition.

The present disclosure relates to a method of tuning an electric charge extraction circuit of a vibrational energy harvester having a mechanical resonator, the method comprising varying, during a first phase, first and second parameters (ψ.sub.1,ψ.sub.2) of the electric charge extraction circuit based on detected harvested power (P.sub.HARVEST), each of the first and second parameters (ψ.sub.1,ψ.sub.2) influencing the amount of damping of the mechanical resonator and at least the first parameter (ψ.sub.1) influencing the resonance frequency of the mechanical resonator, wherein the first and second parameters (ψ.sub.1,ψ.sub.2) are varied during the first phase such that the amount of damping remains constant or varies by less than a first significant amount and the resonance frequency reaches a final level.

The present disclosure is an electromagnetic force control method of a magnetic disk type negative stiffness electromagnetic actuator. The present disclosure relates to the technical field of vibration control. According to the actually required static bearing capacity, the present disclosure determines the positive stiffness k of a mechanical spring required for a magnetic disk type quasi-zero stiffness vibration isolator; and establishes an electromagnetic force mathematical model of a single electromagnet under a condition of magnetic unsaturation. The present disclosure aims at the magnetic disk type quasi-zero stiffness vibration isolator and takes the coil current as an input control variable, so that the electromagnetic force and displacement of the negative stiffness electromagnetic actuator have a linear relationship, thereby changing the non-linear nature of a vibration isolation system, avoiding the multi-stable phenomenon caused by the non-linear electromagnetic force during working, and eliminating complex dynamic behaviors such as jumping when the whole vibration isolator works. Complex sensors and control systems are not needed, and implementation manners are simple and convenient.

A method and device for preventing impact vibration of a lift system include: acquiring a load weight in a lift container; obtaining preset basic parameters of a lift system; according to the load weight in the lift container and the basic parameters of the lift system, determining a fundamental wave vibration period of a lifting rope when the lift system starts; according to the fundamental wave vibration period and preset calculation parameters of the lift system, determining time-varying simulation parameters of an acceleration of the lift system during a lifting process; according to determined time-varying simulation parameters of the acceleration, lifting the lift container.

Methods, systems, and devices are described for mounting an antenna assembly to a vehicle, whereby rotational degrees of freedom between the antenna assembly and the vehicle are constrained. For example, an antenna mount may employ an intermediate structure between the antenna assembly and the vehicle. In various examples, the intermediate structure may be coupled with one of the vehicle or the antenna assembly by a linear coupling, and the intermediate structure may be coupled with the other of the vehicle or the antenna assembly by a planar coupling. The antenna assembly may be coupled with the vehicle by a compliant coupling that provides a centering force between the antenna assembly and the vehicle. According to various examples, rotational movement between the antenna assembly and the vehicle may be suppressed, and vibration from the vehicle to the antenna assembly may be attenuated.

Methods, systems, and devices are described for mounting an antenna assembly to a vehicle, whereby rotational degrees of freedom between the antenna assembly and the vehicle are constrained. For example, an antenna mount may employ an intermediate structure between the antenna assembly and the vehicle. In various examples, the intermediate structure may be coupled with one of the vehicle or the antenna assembly by a linear coupling, and the intermediate structure may be coupled with the other of the vehicle or the antenna assembly by a planar coupling. The antenna assembly may be coupled with the vehicle by a compliant coupling that provides a centering force between the antenna assembly and the vehicle. According to various examples, rotational movement between the antenna assembly and the vehicle may be suppressed, and vibration from the vehicle to the antenna assembly may be attenuated.

A torsional moment acting on a component in a drive train of an aircraft may be determined using at least one sensor, where the determined torsional moment is used for adjusting at least one adjustable damping element located in or on the component and/or for regulating a torsional stiffness in the torque-conducting component. As a result, the torsional load in the component may be reduced.