RU2562445C2 - Test bench for measurement of stato-dynamic characteristics of physical objects - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: invention relates to measurement equipment and can be used for measurement of mass, coordinates of centre of mass and inertia moments of machine-building facilities. The device consists of a dynamometric platform for measurement of mass of an item, a five-component dynamometric element, an oscillation setting device consisting of movable frames connected by hinges and a system of springs connected to the frames; with that, axes of hinges are connected to axes of angle sensors. Besides, the test bench is provided with fasteners providing oscillations only about that axis relative to which inertia moment measurement is made. With that, the five-component dynamometric element consists of four posts of a square section, which are oriented along coordinate axes of the test bench, an upper base on which a physical object is installed by means of a cross piece and a lower base fixed on the dynamometric platform; on edges of each post at the upper base and at the lower base there bonded are strain gauges connected to five bridges for measurement of moments around coordinate axes of the test bench and two lateral forces.

EFFECT: improvement of accurate measurement of inertia moments and coordinates of centre of mass of objects.

12 dwg

Description

The invention relates to the field of mechanical measurements, in particular to the measurement of mass, coordinates of the center of mass and moments of inertia of products.

The task of controlling the high-speed movement of products of space and rocket technology, land and sea transport systems requires a knowledge of the mass, coordinates of the center of mass and moments of inertia of the products. The most reliable method for determining the complex of these parameters is measurement.

A known complex for measuring mass, coordinates of the center of mass and moments of inertia of engineering products (see VV Bogdanov, BC Volobuev and others. "Complex for measuring masses and moments of inertia of engineering products", Measuring technique No. 2, 2002, S. 37 -39).

The complex includes two stands, one of which is designed to measure the mass and coordinates of the center of mass, the other - to measure the moments of inertia of the products. The stand for measuring mass and coordinates of the center of mass consists of two frames, on the horizontal beams of which, with the help of special clamps, a cylindrical product extended over the length is installed. Using vertical rods, the beams are connected to four dynamometers. The bases of the dynamometers are connected to the support posts, which are rigidly fixed to the power foundation. Along the rods are reaction forces, which are measured by dynamometers.

The mass of the product is measured by the sum of the reactions of the dynamometers, and by the combination of reactions and the known coordinates of the dynamometers, two horizontal coordinates of the center of mass. To measure the vertical coordinate, you must rotate the product 90 ° around the longitudinal axis of the product.

The stand for measuring moments of inertia is a frame with four vertical springs, on which the product is installed using special clamps. In places where the springs are attached to the clamps, displacement sensors are located that measure the deformation of the springs. To prevent these points from moving horizontally, guide bushings are provided in the stand design. Thus, the movement of the product is possible only in three degrees of freedom.

Prior to the measurement, a force is applied to the springs, which is then immediately removed and the system begins to make free oscillations in three degrees of freedom. As a result of digital signal processing of each of the sensors, the frequencies and amplitudes of oscillations are used to determine the moments of inertia of the product. To obtain three axial moments of inertia, it is necessary to rotate the product 90 ° around the longitudinal axis.

The main disadvantages of this complex are the following:

- the need to rotate the product through an angle of 90 ° to obtain a measurement result (in many cases, such a rotation is unacceptable according to the technical conditions for the product);

- the mass and coordinates of the center of mass are measured on one stand, and the moments of inertia on another, which leads to additional measurement errors due to inaccurate alignment (mismatch) of the product axes with the axes of the stand.

In connection with the creation of a number of stands, TsAGI has gained some experience in the technique of measuring the inertia moments of various bodies and it has become possible to further improve the methodology for creating such measuring instruments.

The closest constructive solution is the stand created at FSUE TsAGI for measuring the mass, coordinates of the center of mass and inertia tensor of an engineering product (see patent for invention No. 2368880, IPC G01M 1/10, 2008, “Sensors and systems” No. 5, 2010 pp. 24-28; 29-33), containing the frame to which the product is attached, dynamometers, angle sensors, springs, a bed, a dynamometric platform with a frame rotation unit, an oscillation setting device consisting of movable frames interconnected and with a bed with hinges and a system of springs connected to frames, with this axis of the hinges are connected to the axes of the angle sensors.

All necessary measurements are carried out with one installation of the product on the stand.

The stand has two modes of operation - static and dynamic.

In static mode, the mass and three coordinates of the center of mass of the product are measured using a dynamometer platform. The horizontal coordinates of the center of mass are determined by the forces measured by the dynamometers. To measure the vertical coordinate of the product using a rotation node, a series of consecutive tilt angles is specified. From the moments measured using the dynamometer platform and the measured tilt angles, the vertical coordinate of the product’s center of mass is determined.

Moments of inertia are measured in dynamic mode. In this case, the frame with the product make free damped oscillations sequentially around the three orthogonal axes of the stand. Using a dynamometric platform, three dynamic moments are measured, according to which, using the data of angle sensors, the known mass and coordinates of the center of mass, using the digital signal processing apparatus, the moments of inertia of the product are determined.

Previously, a method was developed for determining the angular acceleration from the readings of the angle sensor, see "Sensors and Systems" No. 5, 2012, p. 29 ... 32.

One of the main disadvantages of this solution is the unsatisfactory accuracy of measuring the moments of inertia and the vertical coordinate of the center of mass of products with a configuration elongated along the vertical axis. The reason for this drawback is as follows. When the product oscillates around any of the horizontal axes, the moment vector M acts on the dynamometer platform, which is the sum of three vectors:

(see Sensors and Systems No. 8, 2013, p. 14)

where M _k and M _F are the inertial moments caused by the oscillations of the product around the center of mass (CM) and the fluctuations of the mass m of the product around the axis of rotation;

M _P - positional moment due to the action of gravity. Moments (1) are measured relative to the origin of the dynamometer platform.

The moment M _k is a useful moment, because it is directly related to the measured moments of inertia:

where T is the inertia tensor

;

;

J _x ; J _y ; J _z - central axial, and J _{x · y} = J _{y · x} ; J _{x z} = J _{z x} ; J _{y · z} = J _{z · y} are the centrifugal moments of inertia.

- вектор углового ускорения:

- angular acceleration vector:

, при помощи (2) находим столбцы тензора инерции.Exciting sequentially vibrational systems of the bench and measuring the components of the moment vectors M _k and acceleration

, using (2) we find the columns of the inertia tensor.

The moments M _F and M _P are additional, which must be subtracted from the total measured moment M. Often the additional moments are commensurate with the measured moment M, which is why the useful moment M _{k is} obtained as a small difference of large quantities. As a result, the accuracy of measuring the useful moment, and hence the moments of inertia, decreases.

The magnitudes of the moments M _F and M _{P are} determined by vector products:

where R is the radius vector connecting the origin of the dynamometric platform with the center of mass of the product;

P _C - gravity:

P _C = m g;

m is the mass of the product;

g is the acceleration of gravity;

F _C - the vector of inertial force acting in the CM - is given by the vector product:

R ₀ is the radius vector connecting the axis of rotation (OB) of the frame with the CM of the product.

The sum of the vectors M _F + M _P gives the total vector of the additional moment:

where is the generalized force vector:

Q _C = F _C + P _C.

From relation (5) it can be seen that the value of the total moment vector is determined by the radius vector R. The latter, in turn, depends on the distance of the product’s CM from the origin of the dynamometer platform. To reduce this distance or, equivalently, to reduce the radius vector R constructively is not possible due to the length of the product along the vertical axis.

Another disadvantage of the known solution is the influence of angular deformations of the dynamometer platform, the support frame and other elements of the stand on the accuracy of measuring the coordinates of the center of mass and the moments of inertia of the product.

Consider the error in measuring the vertical coordinate of the center of mass due to the angular deformation of the pressure gauge platform. The basic equation used to determine the coordinates of the center of mass is the positional moment vector:

where i, j, k are the unit vectors of the axes 0X _C Y _C Z _C , whence:

considering that:

we get:

Equation (6) is the initial one when determining the coordinates x _C and y _{C of the} center of mass.

By asking a series of tilt angles sequentially for the product, we get an excess system of equations from which we find x _C and y _C using the least square method.

на упругую систему динамометрической платформы вызывает угловые деформации, и, как следствие, погрешности из мерения координат центра масс. Учитывая, что y_C<<x_C расположим центр масс на вертикальной оси (y_C=0) и, ввиду малости углов φ, примем sinφ=φ, тогда:Action moment $$M_{z_C}$$

on the elastic system of the dynamometric platform causes angular deformations, and, as a consequence, errors in measuring the coordinates of the center of mass. Considering that y _C << x _{C, we} position the center of mass on the vertical axis (y _C = 0) and, since the angles φ are small, we take sinφ = φ, then:

Total increment of the moment:

находим:Assuming

we find:

; x_C=1700 мм; φ=5°We accept:

; x _C = 1700 mm; φ = 5 °

we get:

dφ≤110.61 arc seconds.

Besides:

where from:

where c _φ is the coefficient of angular stiffness of the elastic system of the dynamometric platform.

; x_C=1700 мм.Take: P = 1200 kg;

; x _C = 1700 mm.

From (7) we find:

c _φ ≥3.5 · 10 ⁹ kgf · mm.

Practice shows that it is not possible to implement a dynamometric platform with such a high coefficient of angular stiffness, in addition, monitoring the position of the product with an accuracy of ten arc seconds leads to additional difficulties.

The technical result of this invention is to improve the accuracy of measuring the moments of inertia and the coordinates of the center of mass of the product due to the possibility of transferring the origin of the strain gauge to the center of mass of the product and measuring the tensor of two additional lateral forces.

.The technical result is achieved by the fact that the stand for measuring the static-dynamic characteristics of physical objects, containing dynamometers, angle sensors, springs, a bed, a dynamometer platform, oscillation setting devices, consisting of movable frames connected to each other and to the frame by hinges and a spring system connected to the frames while the axis of the hinges are connected to the axes of the angle sensors, is equipped with clamps that ensure the product oscillates only around the axis relative to which the measurement is currently performed the moment of inertia, and a five-component dynamometric element consisting of four pillars of square section, oriented along the coordinate axes of the bench, the upper base, on which the physical object is mounted by means of a cross, and the lower base, mounted on a dynamometric platform, on the faces of each rack at the upper base and at the lower base are glued strain gauges connected in a five bridges for measuring moments M _X, M _Y, M _Z and two lateral forces and Q _Y Q _Z, the distance between the origin and Horizontal axes of the five-component load cell associated with the length of rack L, the distance between them and the side l h square dependence of the rack:

.

For a more detailed explanation of the invention, we consider the layout of the stand, its design and principle of operation.

In FIG. 1 shows a perspective view of a bench structure.

In FIG. 2 - stand design in two orthogonal projections.

In FIG. 3 - axonometric projection of a five-component dynamometric element.

In FIG. 4 is a diagram of a strain gauge sticker on a rack of a five-component strain gauge element.

In FIG. 5 is a vector diagram of moments and forces during product oscillations around the Z axis.

.In FIG. 6 is a vector diagram and arrangement of strain gages for measuring moment M _Z and force $$Q_{Y_C}$$

.

In FIG. 7 is an electrical diagram of a bridge for measuring moment M _Z.

.In FIG. 8 is an electrical diagram of a bridge for measuring force $$Q_{Y_C}$$

.

.In FIG. 10 is an electrical diagram of a bridge for measuring force $$Q_{Z_C}$$

.

In FIG. 11 - vectors of forces acting on the racks of a five-component tensometric element when measuring the moment M _X.

In FIG. 12 is a circuit diagram of a bridge for measuring the moment M _X.

The physical object 1 (Fig. 1 and Fig. 2) is mounted on the crosspiece 2, mounted on the upper base of the five-component dynamometer element 3, which, with its lower base, is mounted on the dynamometer platform 4, supported by four dynamometers 5. Dynamometers 5 are spaced in space in the horizontal direction coordinate axes and their lower bases are fixed at the vertices of the rectangular inner frame 6 of the oscillation setting device. The sides of the inner frame 6 are parallel to the horizontal axes Y and Z of the stand and the five-component dynamometric element 3. The oscillation setting device consists of movable inner 6, outer 7 and lower 8 frames. The inner frame 6 is connected to the outer frame 7 using two horizontal hinges 9 mounted on the uprights 10 and suspensions 11 mounted on the outer and inner frames, respectively. The outer frame 7 is connected to the lower frame 8 using two horizontal hinges 12 mounted on the uprights 13 and suspensions 14 mounted on the lower frame and the outer frame, respectively. The lower frame 8 is connected to the bed 15 using a vertical hinge 16. The axis of the hinges are directed along the coordinate axes 0XYZ of the stand so that the inner frame 6 can oscillate around the Z axis, the outer frame 7 around the Y axis, and the lower frame 8 around the axis X.

The inner, outer and lower frames are interconnected and with the frame spring system. The outer frame 7 is connected to the lower frame 8 by a pair of springs 17. The inner frame 6 is connected to the outer frame 7 by a pair of springs 18. The lower frame 8 is connected to the frame 15 by two pairs of springs 19. Angle sensors 20, 21, 22 are installed on the shafts of the three hinges. as a result, three independent oscillatory systems are formed, each of which is capable of oscillating around one of the three orthogonal axes of the stand. To prevent arbitrary angular movements of a physical object, the stand is equipped with clamps 23, 24 and 25, which ensure that the physical object vibrates only around the axis relative to which the moment of inertia is currently being measured. Each pair of frames is equipped with its own device for setting oscillations.

The main feature of this stand is the presence of a five-component dynamometric element (PDE) 3 (Fig. 1 and Fig. 2), consisting of two bases - the upper 26 (Fig. 3), the lower 27 and four racks 28 (28 (+ Y) , 28 (-Y), 28 (+ Z) and 28 (-Z)). On the faces of the racks are glued twenty strain gauges R ₁ ... R ₂₀ (Fig. 4), which are connected in five measuring bridges. The origin (NK), relative to which the moments M _Y and M _Z are measured, is located at a distance x _H from the horizontal axes of the five-component dynamometric element (Fig. 5) and (Fig. 6). The proper coordinate origin of the five-component dynamometric element is located at the intersection of its axes of symmetry. The stand works as follows. Like the prototype, it has two operating modes - dynamic and static modes.

In dynamic mode, the moments of inertia and the coordinates of the center of mass are measured, and in static mode, the weight of the product (mass).

In the stand adopted for the prototype, four components of the load vector are measured: three moments - M _x , M _y , M _z and vertical force F _X. All four components are measured using a torque platform.

, $$Q_{z_C}$$

. Вертикальная сила, как и в прототипе, измеряется при помощи динамометрической платформы, а моменты и боковые силы - пятикомпонентным тензометрическим элементом.In this solution, it is proposed to measure the component of the load vector - three moments M _x , M _y , M _z and three forces, vertical F _X and two lateral $$Q_{y_C}$$

, $$Q_{z_C}$$

. The vertical force, as in the prototype, is measured using a dynamometric platform, and the moments and lateral forces are measured with a five-component tensometric element.

.When measuring the axial moment of inertia about the Z axis, the latch 23 (Fig. 1 and Fig. 2) is open, and the latches 24 and 25 are closed and prevent angular movement of the product around the X and Y axes. Lower frame 8 with external 7, internal 6 frames, with the dynamometer platform 4, the five-component dynamometer element 3, the crosspiece 2 and the product 1 deviates by an angle φ _Z about the axis Z of the stand and under the action of the springs 18 (Fig. 1 and Fig. 2) performs damped angular oscillations. The moments applied to the physical object are measured by a five-component dynamometer 3, and the current angular position is measured by an angle sensor 20, from which the angular acceleration is determined by digital signal processing

.

Figure 5 shows a vector diagram of the forces and moments acting in a fixed (inertial) coordinate system 0XYZ connected with a stand and a moving system 0X _C Y _C Z _C connected with a physical object during oscillations of a physical object around a rotation axis (OB) parallel to the Z axis .

The physical object is characterized by mass m, three coordinates x _C , y _C , z _{C of the} center of mass and three axial moments of inertia J _x , J _y , J _z .

и $$Q_{y_C}$$

вектора силы Q_C и момента $$M_{z_k}$$

вдоль оси Z. Момент M_Z, действующий относительно начала координат:When the physical object oscillates around the Z axis (Fig. 5), the components act in the center of mass $$Q_{x_C}$$

and $$Q_{y_C}$$

force vector Q _C and moment $$M_{z_k}$$

along the Z axis. Moment M _Z , acting relative to the origin:

where x _c is the coordinate of the product’s CM in the axes 0X _C Y _C Z _C.

The value of the first term in the right-hand side of (8) with x _C = const:

defines x _H - position of the origin.

If you do not resort to the transfer of the origin, then the own coordinate origin of the tensor is realized - x _H = 0, then:

Typically, rocket products are elongated along the X axis,

оказывается соизмеримым с измеряемым моментом M_Z и точность измерения момента оказывается недостаточной.Resulting moment

It turns out to be commensurate with the measured moment M _Z and the accuracy of the moment measurement is insufficient.

Consider the principle of transferring the origin to a given point x = x _H and the relation x _H with the parameters of the strain gauge.

испытывают деформации растяжения-сжатия и деформации изгиба. Указанные деформации на противоположных гранях стоек, т.е. в местах расположения тензорезисторов всегда имеют противоположные знаки (фиг. 6). Для измерения момента M_Z используются тензорезисторы R₁, R₂, R₃, R₄, соединенные в измерительный мост (фиг. 7). Относительные деформации $$\epsilon =\frac{\Delta l}{l}$$

стоек под тензорезисторами R₁…R₄ In the general case, struts 28 (28 _{(+ Y)} , 28 _(-Y) , 28 _{(+ Z)} and 28 _(-Z) ) of a five-component dynamometer under the action of force $$Q_{y_C}$$

experience tensile-compression and bending deformations. These deformations on opposite faces of the uprights, i.e. in the locations of the strain gauges always have opposite signs (Fig. 6). To measure the moment M _Z , strain gages R ₁ , R ₂ , R ₃ , R _{4 are used} , connected to a measuring bridge (Fig. 7). Relative strain $$\epsilon =\frac{\Delta l}{l}$$

racks under the strain gages R ₁ ... R ₄

where S is the area of the rack:

S = h ²

W - moment of resistance:

E is Young's modulus.

The first terms (9) are tensile-compression deformations, and the second are bending deformations. The ratio of the output voltage increment to the supply voltage of the bridge is expressed by the formula:

и используя (9) и (10), получим:Given that $$\frac{\Delta R}{R}=k\cdot \epsilon$$

and using (9) and (10), we obtain:

where k is the coefficient of strain sensitivity.

относительно начала координат.The first term (11) represents a signal proportional to the moment of force $$Q_{y_C}$$

relative to the origin.

на результат измерения момента. С целью исключения указанного влияния положим:The second term (11) reflects the influence of force $$Q_{y_C}$$

on the result of measuring the moment. In order to exclude this effect, we put:

Whence for x _H we get:

For example, for a real strain gauge:

L = 60 mm; h = 9 mm; L _Y = 250 mm;

we get: x _H = 1250 mm.

Typically, the x _H coordinate of products is of the order of: x _H ≈1500 mm;

; и

.then:

; and

.

и связанных с ним моментов инерции.Thus, the transfer of the origin to the point x _H = 1250 mm allows us to reduce the first term of equation (8) by six times and thereby increase the accuracy of measuring the useful moment $$M_{Z_k}$$

and associated moments of inertia.

предназначены тензорезисторы R₅, R₆, R₇, R₈, соединенные в измерительный мост (фиг. 8).To measure strength $$Q_{Y_C}$$

designed strain gauges R ₅ , R ₆ , R ₇ , R ₈ connected to the measuring bridge (Fig. 8).

тензорезисторы R₅, R₇ получают положительные, а тензорезисторы R₆, R₈ отрицательные приращения сопротивления. Относительный выходной сигнал моста:Under the influence of force $$Q_{y_C}$$

strain gages R ₅ , R ₇ receive positive, and strain gages R ₆ , R ₈ negative increments of resistance. Relative bridge output:

When measuring the axial moment of inertia about the Y axis, the latch 24 (Fig. 1 and Fig. 2) is open and allows the physical object to oscillate around the Y axis, and the latches 23 and 25 are closed and prevent angular movement of the physical object around the X and Z axes. Outer frame 7 with an internal frame 6 mounted on it, a dynamometer platform 4, a five-component dynamometer element 3, a crosspiece 2 and a product 1, it deviates by an angle φ _Y about the axis Y of the stand and under the action of the springs 18 performs angular damped oscillations. The moments applied to the physical object are measured by a five-component dynamometer 3, and the current angular position is measured by an angle sensor 21.

предназначены тензорезисторы R₁₃, R₁₄, R₁₅, R₁₆ соединенные в измерительный мост (фиг. 10).To measure the moment M _Y , strain gages R ₉ , R ₁₀ , R ₁₁ , R _{12 are used} , connected to a measuring bridge (Fig. 9). To measure strength $$Q_{Z_C}$$

strain gages R ₁₃ , R ₁₄ , R ₁₅ , R ₁₆ are designed connected to a measuring bridge (Fig. 10).

When measuring the axial moment of inertia about the X axis, the latch 25 (Fig. 1 and Fig. 2) is open, and the latches 23 and 24 are closed and prevent the angular movement of the physical object around the Y and Z axes. The lower frame 8 with external 7, internal 6 frames, with a dynamometer platform 4, a five-component dynamometer element 3, a crosspiece 2 and a product 1 deviates by an angle φ _X around the axis X of the stand and under the action of the springs 19 (Fig. 1 and Fig. 2) performs damped angular oscillations. The moments applied to the physical object are measured by a five-component dynamometer 3, and the current angular position by the angle sensor 22.

To measure the moment M _x (Fig. 11), strain gages R ₁₇ , R ₁₈ , R ₁₉ , R _{20 are used} , connected to a measuring bridge (Fig. 12).

вызывает появление пары сил F_y в направлении оси Y:Act $$M_{x_C}$$

causes the appearance of a pair of forces F _y in the direction of the Y axis:

.

.

As a result, the strut 28 _(-Z) (Fig. 11) is deformed in the positive direction, and the strut 29 _{(+ Z) the} negative axis Y. The strain gauges R ₁₇ , R ₁₉ receive positive, and R ₁₈ , R ₂₀ negative resistance increments.

Relative bridge output:

An important issue affecting the accuracy of measuring the coordinates of the center of mass and moments of inertia is the number of measured components of the load vector.

The ability to measure an additional two lateral forces can significantly improve the accuracy of measuring the coordinates of the center of mass and the moments of inertia of physical objects. In FIG. Figure 5 shows a vector diagram corresponding to the vibrations of a physical object around the Z axis. In the diagram, the origin is moved along the оси axis to a distance x _n . The radius vectors R ₀ and R connect the axis of rotation (OB) and NC with the center of mass (CM).

и $$Q_{x_C}$$

. Суммарный момент M_Z, действующий в начале координат:The vector of generalized force Q with components acts in the CM $$Q_{y_C}$$

and $$Q_{x_C}$$

. The total moment M _Z acting at the origin:

- момент, соответствующий колебаниям изделия вокруг ЦМ.Where $$M_{Z_k}$$

- the moment corresponding to the oscillations of the product around the CM.

In static mode:

;

.Where

;

.

и $$P_{y_C}$$

, получим избыточную систему уравнений, которая решается методом наименьших квадратов относительно неизвестных координат x_с и y_с. Координата x_н является одним из параметров тензоэлемента, который определяется на калибровочном стенде.By producing a series of consecutive angles of inclination of a physical object and measuring projections $$P_{x_C}$$

and $$P_{y_C}$$

, we obtain an excess system of equations, which is solved by the least squares method with respect to the unknown coordinates x _s and y _s . The coordinate x _n is one of the parameters of the strain gauge, which is determined on the calibration stand.

и $$P_{y_C}$$

измеряются непосредственно без участия углов наклона физического объекта. По этой причине угловые деформации динамометрической платформы и других элементов стенда не оказывают влияния на точность измерения координат ЦМ физического объекта.Note that in the proposed solution, in contrast to the prototype, projection $$P_{x_C}$$

and $$P_{y_C}$$

are measured directly without the participation of the tilt angles of the physical object. For this reason, the angular deformations of the dynamometer platform and other elements of the stand do not affect the accuracy of measuring the coordinates of the CM of the physical object.

, $$Q_{X_C}$$

и, учитывая известные координаты (x_C-x_H) и y_C, определяется составляющая полезного момента $$M_{Z_k}$$

; далее, используя (2), определяется момент инерции физического объекта.In dynamic mode, M _Z are measured, $$Q_{Y_C}$$

, $$Q_{X_C}$$

and, given the known coordinates (x _C -x _H ) and y _C , the component of the useful moment is determined $$M_{Z_k}$$

; Further, using (2), the moment of inertia of a physical object is determined.

Claims (1)

A stand for measuring the statodynamic characteristics of physical objects, comprising dynamometers, angle sensors, springs, a bed, a dynamometer platform, an oscillation setting device consisting of movable frames connected to each other and to the bed by hinges and a spring system connected to the frames, while the hinge axes are connected with the axes of the angle sensors, characterized in that the stand is equipped with clamps that provide the product to oscillate only around the axis relative to which the moment is not currently measured tion, and a five-component dynamometer element, consisting of four pillars of square section, oriented along the coordinate axes of the bench, the upper base, on which the physical object is mounted by means of a cross, and the lower base, mounted on a dynamometric platform, on the faces of each rack at the upper base and at the lower the bases are glued with strain gauges connected in five bridges to measure the moments M _X , M _Y , M _Z and two lateral forces Q _Y and Q _Z , while the distance between the origin and horizontal the axes of the five-component dynamometer element are connected with the length of the struts L, the distance between them l and the side h of the square section of the strut as follows:

.

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