17 results about "Normal force" patented technology

The present application belongs to the field of geotechnical engineering in-situ testing technology, and discloses a kind of in-situ shear test device and test method in field drilling, including ground driving system, drill rod, centralizer and shear probe, ground driving system includes shear loading assembly, tangential pressure assembly and normal pressure assembly, tangential pressure assembly is connected with shear loading assembly by hydraulic line, for driving shear loading assembly to output tangential force;Drill rod bottom end is connected with shear probe, normal pressure assembly is connected with shear probe by hydraulic line, drives shear probe to output normal force;Shear probe is equipped with centralizer, and centralizer is used to contact with the inner wall of borehole;Tangential pressure assembly and normal pressure assembly are all servo motor driven hydraulic equipment, and are controlled by industrial computer;The accurate constant pressure control of normal stress is realized by ground driving system, test is more accurate, and is suitable for soft soil to hard rock extensive stratum, and centralizer can prevent eccentric force from affecting test accuracy.

An actuator assembly comprising first (10) and second parts (20) that are movable relative to each other along at least one movement path M in at least one degree of freedom of movement; an actuator arrangement (40) comprising at least one actuator (40a) configured, on actuation, to cause an actuating force to be applied to the second part so as to move the second part relative to the first part along the at least one movement path within a range of movement; a biasing arrangement (30) configured to: apply, when the second part is positioned relative to the first part within the range of movement and at positions that are located along the at least one movement path and on opposite sides from a set position, a lateral force to the second part acting in a direction along the at least one movement path and away from the set position; wherein at least one common component is configured to apply to the second part both i) the lateral force and ii) the actuating force or a normal force for loading a bearing arrangement (50) that guides the movement of the second part relative to the first part along the at least one movement path.

This invention discloses a method, system, and medium for measuring stress and earth pressure behind retaining walls / piles under localized overload. Addressing the shortcomings of existing technologies in simultaneously considering stress or earth pressure measurement under localized overload and rotational displacement of retaining walls / piles, this invention first solves the problem of measuring additional vertical stress behind retaining walls / piles under localized overload. The calculation model is constructed by combining theoretical derivation of the mechanical response of a semi-infinite elastic body surface subjected to a concentrated normal force with experimental test data analysis. Secondly, the invention solves the problem of measuring earth pressure behind retaining walls / piles under localized overload. The optimized scheme provides identification schemes for eight measurement conditions under five types of rotational displacement modes of retaining walls / piles, as well as non-limit active earth pressure measurement schemes under each measurement condition. The measurement method of this invention has a clear calculation model, easily obtainable parameters, and high engineering applicability. This invention also provides a force measurement system based on the measurement method and a medium for carrying the measurement method.

The application provides a design method of a U-shaped steel clamp for an aviation wheel, and belongs to the technical field of aviation brake wheels. The method determines the compressive stress of the steel clamp according to the normal force transmitted by the guide rail of the aviation wheel to the steel clamp and the contact area between the guide rail of the aviation wheel and the steel clamp. When the compressive stress of the steel clamp meets the requirements, the dangerous shear cross-sectional area of the steel clamp is determined. Then, the maximum shear stress of the steel clamp is determined according to the dangerous shear cross-sectional area of the steel clamp and the determined normal force. When the shear stress of the steel clamp meets the requirements, the bending modulus of the cross section of the steel clamp is determined. After that, the maximum bending moment borne by the steel clamp is determined according to the determined normal force. Finally, the maximum bending stress of the steel clamp is determined according to the determined bending modulus of the cross section and the maximum bending moment, and whether the maximum bending stress of the steel clamp meets the requirements is determined. The method solves the problem that the U-shaped steel clamp is prone to fracture, resulting in loss of friction torque and functional failure of the rotor assembly.

This invention discloses a finite element simulation method and system for a suspension bridge tower top saddle. The method includes: collecting multiple types of parameters; iteratively solving for tangential and normal forces based on an initial tangential stiffness matrix; calculating the actual contact friction coefficient based on the coupling relationship between temperature and contact normal pressure; calculating a tangential correction coefficient based on the actual contact friction coefficient, the ratio of tangential to normal forces, and the linkage relationship between the saddle geometric parameters; dynamically adjusting the tangential stiffness matrix based on the correction coefficient, the saddle pre-offset, and the synergistic relationship between cable stress; constructing a finite element model and simulating it; and iteratively optimizing until convergence. The system corresponds to the modules described above. This invention optimizes simulation accuracy through multi-factor coupling and linkage, adapting to complex working conditions and providing reliable support for the design and construction of suspension bridges.

The application discloses a bolted joint normal contact stiffness driven assembly preload and fractal parameter optimization method, and belongs to the field of dynamic characteristic analysis of numerical control machine tools. The method comprises the following steps: a mapping relationship model of the normal contact stiffness of the bolted joint, the normal force, the fractal dimension of the joint surface and the surface roughness parameter is established; the normal contact stiffness under the steady state is taken as the target, and the inflection point is defined as the optimization result of the normal force, the fractal dimension of the joint surface and the surface roughness parameter; a normal force and assembly preload relationship model is established, and an assembly preload optimization method considering the safety factor is proposed; a cutting parameter and joint surface fractal dimension and surface roughness parameter relationship model based on a neural network is constructed, and the cutting parameter is optimized reversely. The application not only optimizes the assembly preload and the surface characteristic parameter from the assembly dimension, but also controls the surface characteristic parameter from the manufacturing angle, and has important engineering value for improving the normal contact stiffness of the bolted joint and the dynamic characteristics of the whole machine.

The invention discloses a normal force adjustable two-dimensional foundation excitation dry friction experimental device, which comprises an optical platform, a vibration exciter and a foundation framework, a two-dimensional translation sliding table is supported on the bottom surface of the foundation framework, a lifting platform is arranged in the foundation framework, a foundation friction plate is fixedly arranged at the top end of the lifting platform, and a vibration exciter is arranged on the foundation friction plate. An elastic supporting friction plate is arranged on the upper side of the basic friction plate, is suspended at the upper part of the basic frame through the stretching of a spring, and forms a friction pair with the basic friction plate; a balance weight disc is fixedly arranged in the middle of the top face of the elastic bearing friction plate. Three-way acceleration sensors are arranged between the top face of the balance weight disc and the bottom face of the base frame and between the lifting platform and the bottom face of the base frame. The two vibration exciters are arranged outside the foundation frame, and an angle of 90 degrees is formed between output ejector rods of the two vibration exciters. According to the invention, the dynamic two-dimensional friction experiment capable of simulating elastic supporting conditions and accurately adjusting normal force can be carried out, so that the nonlinear dynamic characteristics of the friction pair as a complete vibration system can be deeply studied.

An assembly comprising: a first part defining a primary axis; a second part which is movable with respect to the first part; and a third part which is movable with respect to the first and second parts and comprises a first friction surface which is biased against a second friction surface with a normal force. The second friction surface is disposed on one of the first and second parts. The assembly further comprises a first SMA element arranged to drive movement of the third part along a first direction, at least a component of which is perpendicular to the primary axis. The third part is mechanically coupled to the first and second parts such that movement of the third part along the first direction causes movement of the second part relative to the first part along a second direction, different to the first direction. At least a component of the second direction is parallel to the primary axis. The first SMA element is arranged such that contraction of the first SMA element reduces or removes the normal force between the first and second friction surfaces. The assembly further comprises a force-application arrangement configured to: apply a force between the second part and the first part, thereby reducing or removing the normal force between the first and second friction surfaces, and cause movement of the second part along a third direction, at least a component of which is parallel to the primary axis and opposite to the at least a component of the second direction.

The invention belongs to the technical field of aircraft strength and rigidity design, and particularly relates to a shear deformation component calculation method of a rectangular sandwich panel with four simply supported sides under normal force. The method includes the following steps that firstly, a coordinate system is defined based on the four-side simply-supported rectangular sandwich panel; 2, defining shearing parameters of the four-side simply-supported rectangular sandwich panel structure; 3, establishing an infinitesimal body balance equation; 4, establishing a control equation according to the infinitesimal Hooke's law; and 5, solving the shear deformation.

Friction devices and systems for dissipating energy from a structure are provided. In various embodiments, the friction device may include a first friction assembly including a first plate and a second plate and configured to generate a first friction force by a movement of the first plate relative to the second plate; a first fastener assembly configured to exert a first normal force onto the first friction assembly; a second friction assembly including auxiliary pads and configured to generate a second friction force by a movement of the auxiliary pads relative to the second plate when the auxiliary pads are coupled to the first plate; and a second fastener assembly configured to exert a second normal force onto the second friction assembly, in which energy is dissipated by a total friction force that is a sum of the first friction force and the second friction force and discretely variable.

The application discloses a design method of a blade connecting interface and a hybrid structure fan blade. The design method of the blade connecting interface comprises the following steps: S1, assuming a curve of the connecting interface and obtaining a curve function of the curve, and decomposing external force on the connecting interface into a tangent force function and a normal force function; S2, obtaining an interface shear strength function by using the normal force function; S3, making the tangent force function less than the interface shear strength function, and obtaining a relationship between the external force on the connecting interface and the curve function; S4, obtaining a relationship between an external force load and the curve function; S5, obtaining a specific form of the curve function according to the determined external force load, if the curve form cannot be realized due to various reasons, returning to S1 to start iteration, and if the curve form can be realized, executing step S6; S6, processing a metal leading edge panel and a composite material according to a corresponding form of the connecting interface; and S7, splicing. The force borne by the interface is converted into a tangent force and an interface pressure, and finally the shear deformation or stress of the interface is reduced.

The invention relates to a method of determining a mechanical action torque component at a guide point of a cutting blade (L) for a cutting machine, the cutting blade being guided into a presser foot (P) of a cutting head of the cutting machine. The method comprises positioning a five-component force transducer on the presser foot, wherein the five-component force transducer comprises a plurality of sensors capable of determining a normal force, a lateral force, a roll torque, a pitch torque, and a yaw torque of the cutting blade; establishing a calibration matrix of the force transducer; determining forces experienced by the cutting blade in three dimensions based on measurements obtained from the sensors and the calibration matrix.

An actuator assembly 1 comprises first 10 and second 20 parts that are movable relative to each other, each having a friction surface 10f, 20f and a biasing arrangement 30 to apply a normal force bias

The invention discloses a flexible three-dimensional capacitive force sensor and a preparation and calculation method thereof. The flexible three-dimensional capacitive force sensor comprises a flexible base, a force bearing column integrally formed with the flexible base, five capacitive sensing units arranged around the force bearing column and a flexible boss top cover arranged above the flexible base. The top capacitance sensing unit is used for detecting normal force, and the four side wall capacitance sensing units are used for detecting shearing force in two orthogonal directions in pairs; through the spatial distribution of the top and side wall sensing units and the design of a load transmission path between the boss top cover and the bearing column body, the primary decoupling of normal force and shear force on the structural level is realized. In addition, a capacitance signal acquisition module is arranged in a matched mode, feature extraction and neural network mapping are carried out on five paths of capacitance signals, real-time calculation of normal force and shearing force in two orthogonal directions is achieved, and therefore compensation is carried out on non-linear and miniaturized structure residual coupling of the flexible material.

An actuator assembly (1) comprising first and second parts (10, 20) that are movable relative to each other, the first part comprising a first friction surface (lOf) and the second part comprising a second friction surface (20f); at least two SMA elements (49) configured, on actuation, to cause actuation forces in opposite directions to be applied to the second part for moving the second part in opposite directions relative to the first part; a biasing arrangement (30) configured to apply a normal force biasing the first and second friction surfaces against each other, thereby giving rise to at least part of a static frictional force that is capable of constraining relative movement of the first and second parts when the at least two SMA elements are not actuated; wherein the at least two SMA elements are configured, on actuation, to cause reduction of the normal force between the first and second friction surfaces, thereby reducing the static frictional force; and further comprising at least one additional actuator (45) configured, on actuation, to modulate the static frictional force.

A bearing assembly comprising a first part, a second part and a constraint device. The first part comprises a first bearing member defining a first bearing surface. The second part comprises a second bearing member. The second part is configured to rotate relative to the first part about an axis of rotation, such that the second bearing member rolls along the first bearing surface and exerts a normal force which can be represented by a point force acting on the first bearing surface at a contact point. The constraint device is configured to constrain a relationship between a position of the contact point along the first bearing surface in at least one direction radial to the axis of rotation and an orientation of the second part about the axis of rotation over at least a portion of a range of rotation of the second part.

This application relates to the field of tunnel boring equipment technology, and discloses a method and system for predicting the normal force of a cutter roller that takes into account rotational asymmetry. The method includes: obtaining parameters such as rock mass strength, penetration depth, and cutter geometry; calculating and superimposing the areas of the inner and inner compression zones of the cutter roller, and spreading them out to the circumference of the rotation trajectory to determine the cutting groove width; calculating the contact arc using the penetration depth and cutter radius, and deriving the total contact area in conjunction with the cutting groove width; calculating the contact pressure and integrating it along the total contact area to obtain the single cutter rock-breaking resultant force; setting the point of application of the resultant force to pass through the cutter axis and bisect the contact angle corresponding to the contact arc, and decomposing the resultant force to obtain the single cutter rock-breaking normal force. This invention transforms the spatial rock-breaking destruction zone into a planar equivalent integration domain, eliminating the theoretical errors caused by the traditional straight-line cutting assumption and improving the accuracy of the cutter normal force calculation.