Time grating sensor for spherical multi-dimensional rotation angle measurement and mounting structure for time grating sensor

Abstract

A time grating sensor for spherical multi-dimensional rotation angle measurement. The time grating sensor comprises a stator base body (1) and a rotor base body (2). The stator base body (1) is spherical shell-shaped, the rotor base body (2) is spherical and located in the spherical shell of the stator base body (1), and a gap is reserved between the surface of the rotor base body (2) and the inner surface of the stator base body (1), so that the rotor base body (2) is suspended and concentric with the stator base body (1). Six excitation units having the same shape and size are uniformly distributed at intervals on the inner surface of the stator base body (1). The centers of the six excitation units are located at the centers of six faces of a cube externally tangent to the inner surface of the stator base body (1). Eight sensing units having the same shape and size are uniformly distributed at intervals on the surface of the rotor base body (2). The eight sensing units are respectively symmetrically distributed on eight quadrants of a space rectangular coordinate system taking the center of the rotor base body (2) as the origin. Also disclosed is a mounting structure for the time grating sensor for spherical multi-dimensional rotation angle measurement. The solution above can realize high-accuracy multi-dimensional rotation angle measurement in a spherical space, simple structure, thorough decoupling, and strong anti-interference capability.

Description

A spherical multidimensional rotation angle measurement time grid sensor and its mounting structure Technical Field

[0001] This invention relates to time grating sensing technology, specifically to a spherical multidimensional rotation angle measurement time grating sensor and its mounting structure, belonging to the field of precision angular displacement measurement. Background Technology

[0002] Currently, the level of multi-dimensional and multi-parameter measurement technology has become an important factor in measuring the international competitiveness of my country's manufacturing industry, and its importance will become increasingly prominent in the new round of global competition in high-end manufacturing. Simply using multiple independent sensors in combination for measurement is no longer sufficient to meet the new demands of intelligent manufacturing processes. Achieving multi-dimensional and multi-parameter measurement with a single sensing unit has become a development trend in the field of precision inspection technology. Spatial multi-dimensional rotational angular displacement measurement is a method of rotation around a constant center in multiple degrees of freedom directions. When using a ball joint as a carrier, it can be transformed into measuring the multi-degree-of-freedom rotation of a spherical rotor around the center of a constrained ball socket. For traditional industrial robot joints, if high-precision measurement of the spatial rotation angle of a ball joint can be achieved, ball joints can be used to replace traditional single-degree-of-freedom rotary joints, thereby effectively reducing the number of joints used, simplifying the system structure, and improving the system's tracking accuracy and dynamic performance. However, conventional measuring instruments and equipment cannot achieve high-precision detection of the multi-dimensional rotation angle of a ball joint, especially in situations where structural dimensions are limited.

[0003] In recent years, a clock pulse-based angular displacement time-grating sensor (publication number CN102425987B) has been developed in China, using clock pulses as the displacement measurement reference. This sensor uses high-frequency clock pulses as the measurement reference and employs an alternating electric field constructed by a parallel plate capacitor to directly couple the required electric traveling wave signal. The angular displacement value is obtained by phase interpolation of the induced signal using the high-frequency clock pulse, enabling high-precision angular displacement measurement. However, current electric field-based angular displacement time-grating sensors can only perform single-dimensional angular displacement measurement and cannot achieve multi-dimensional angular displacement measurement in spherical space. Summary of the Invention

[0004] In view of the above-mentioned shortcomings of the existing technology, the purpose of this invention is to provide a spherical multidimensional rotation angle measurement grating sensor and its installation structure. This invention can realize high-precision spherical space multidimensional rotation angle measurement, and has a simple structure, thorough decoupling, and strong anti-interference ability.

[0005] The technical solution of this invention is implemented as follows:

[0006] A spherical multi-dimensional rotation angle measuring time grating sensor includes a stator base and a rotor base. An excitation unit is provided on the stator base, and an induction unit is provided on the rotor base. The stator base is in the shape of a spherical shell, and the rotor base is in the shape of a sphere and is located inside the spherical shell of the stator base. There is a gap between the surface of the rotor base and the inner surface of the stator base, so that the rotor base is suspended and concentric with the stator base. The excitation unit consists of 6 pieces with exactly the same shape and size, and they are evenly spaced and distributed on the inner surface of the stator base. The centers of the 6 excitation units are located at the centers of the six faces of a cube that is externally tangent to the inner surface of the stator base.

[0007] The induction unit consists of 8 pieces with exactly the same shape and size, and they are evenly spaced and distributed on the surface of the rotor base. The 8 induction units are symmetrically distributed in 8 quadrants of a space rectangular coordinate system with the center of the rotor base as the origin.

[0008] Furthermore, each excitation unit is composed of a metal pole piece made of a conductive material. The six metal pole pieces corresponding to the 6 excitation units are closely attached to the inner surface of the stator base, and the outer surface radius of each excitation unit is equal to the inner surface radius of the stator base.

[0009] Each induction unit is composed of a metal pole piece made of a conductive material. The eight metal pole pieces corresponding to the 8 induction units are closely attached to the outer surface of the rotor base, and the inner surface radius of each induction unit is equal to the outer surface radius of the rotor base.

[0010] Furthermore, the angle size occupied by each excitation unit is θ S , and the angle occupied by the interval between adjacent two excitation units is δ S = π / 2 - θ S ;

[0011] The angle size occupied by each induction unit is θ R , and the angle occupied by the interval between adjacent two induction units is δ R = π / 2 - θ R .

[0012] Furthermore, the center of the rotor base is hollowed out, and the hollowed-out part is spherical.

[0013] Furthermore, the outer contour shape of the excitation unit is a spherical quadrilateral or a spherical circle, a spherical quadrilateral with a hollow center, or a spherical circle with a hollow center; the outer contour shape of the induction unit is a spherical triangle or a spherical circle, a spherical triangle with a hollow center, or a spherical circle with a hollow center.

[0014] Furthermore, all the centers of the excitation units are hollowed out. There is an installation hole on the stator base that penetrates through the inside and outside, and this installation hole is directly opposite to the hollowed-out part of one of the excitation units, so that the surface of the rotor base is communicated with the outside through this installation hole and the corresponding hollowed-out part.

[0015] The present invention also provides an installation structure for a spherical multi-dimensional rotary angle measurement time grating sensor. The spherical multi-dimensional rotary angle measurement time grating sensor is the aforementioned spherical multi-dimensional rotary angle measurement time grating sensor. The stator base body is rotatably connected to the stator driving turntable through a stator support shaft. The excitation electrode is connected to an external excitation source through a signal line penetrating the housing of the stator base body. The rotor base body is rotatably connected to the rotor driving turntable through a rotor support shaft and is suspended in the stator base body. The signal line of the induction electrode is led out from the stator base body through the rotor support shaft. The rotor support shaft and the stator support shaft are perpendicular to each other.

[0016] Further, one end of the rotor support shaft is integrally formed with the surface of the rotor base body and avoids the area where the induction unit is located. The other end of the rotor support shaft passes through the installation hole on the surface of the stator base body and the corresponding hollow part in the middle and then is connected to the rotor driving turntable.

[0017] Furthermore, all the induction units are hollowed out in the center. One end of the rotor support shaft is integrally formed with the surface of the rotor base body through the hollow area of one of the induction units so as to avoid the area where the induction unit is located.

[0018] Further, one end of the stator support shaft is integrally formed with the outer surface of the stator base body, and the other end of the stator support shaft is connected to the stator driving turntable. There is a rotational clearance between the rotor support shaft and the installation hole on the surface of the stator base body and the corresponding hollow part. The rotational angle of the stator support shaft is limited by this rotational clearance.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention realizes simultaneous coding in the spherical space around the orthogonal directions of X and Z by arranging six excitation units in a staggered manner. The induction units pick up signals by arranging in a pairwise differential structure. The coupling signals in the non-measurement direction are filtered by summing the output signals of two adjacent induction units through an adder, and the common-mode interference is eliminated by taking the difference of the differential signals through a subtractor. Thereby, the signal decoupling ability is further improved, the decoupling is complete, the anti-interference ability is strong, high-precision spherical multi-dimensional rotary angle displacement measurement is realized, and the structure is simple and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1 is a relative relationship diagram between the stator base body and the rotor base body in Embodiment 1.

[0022] FIG. 2 is a schematic structural diagram of the stator base body in Embodiment 1.

[0023] FIG. 3 is a schematic structural diagram of the rotor base body in Embodiment 1.

[0024] FIG. 4 is a schematic diagram of angular displacement calculation in Embodiment 1.

[0025] Figure 5 is a schematic diagram of the relative position relationship of the stator substrate excitation unit in Embodiment 1.

[0026] Figure 6 is a schematic diagram of signal processing in Embodiment 1.

[0027] Figure 7 is a schematic diagram of the shape of the stator substrate excitation unit in Embodiment 2.

[0028] Figure 10 is a schematic diagram of the shape of the rotor substrate induction unit in Embodiment 5.

[0029] Figure 9 is a schematic diagram of the shape of the stator substrate excitation unit in Embodiment 4.

[0030] Figure 10 is a schematic diagram of the shape of the rotor substrate induction unit in Embodiment 5.

[0031] Figure 11 is a schematic diagram of the shape of the rotor substrate induction unit in Embodiment 6.

[0032] Figure 12 is a schematic diagram of the shape of the rotor substrate induction unit in Embodiment 7.

[0033] Figure 13 is a schematic diagram of the installation structure of the time grating sensor for spherical multi-dimensional rotation angle measurement of the present invention. Detailed implementation manners

[0034] The present invention will be described in detail below with reference to the accompanying drawings and specific implementation manners.

[0035] A time grating sensor for spherical multi-dimensional rotation angle measurement of the present invention includes a stator substrate and a rotor substrate. An excitation unit is provided on the stator substrate, and an induction unit is provided on the rotor substrate. The stator substrate is in the shape of a spherical shell, the rotor substrate is in the shape of a sphere and is located inside the spherical shell of the stator substrate. A gap is left between the surface of the rotor substrate and the inner surface of the stator substrate so that the rotor substrate is suspended and concentric with the stator substrate.

[0036] The excitation units are 6 in number with exactly the same shape and size, evenly spaced and distributed on the inner surface of the stator base body without contacting each other, and are respectively called A, B, C, D, E, and F; the centers of the 6 excitation units are located at the centers of the six faces of a cube that is externally tangent to the inner surface of the stator base body. The 6 excitation units of the present invention are pairwise symmetric with respect to the XOY plane, the XOZ plane, and the YOZ plane, that is, the 6 excitation units are respectively located on the coordinate axes X+, X-, Y+, Y-, Z+, and Z-, and the distances from the 6 excitation units to the coordinate origin O are equal. Among the 6 excitation units, it can be considered that 4 excitation units A, B, C, and D rotate around the Z-axis, and 4 excitation units A, E, C, and F rotate around the X-axis, where the excitation unit A and the excitation unit C are the excitation units shared by the rotation around the Z-axis and the rotation around the X-axis. Of course, because of the symmetric arrangement without difference in the X, Y, and Z directions, other interpretations can also be made, such as four excitation units rotating around the Z-axis and four rotating around the Y-axis, where two excitation units are shared by the rotation around the Z-axis and the Y-axis; or four excitation units rotating around the X-axis and four rotating around the Y-axis, where two excitation units are shared by the rotation around the X-axis and the Y-axis.

[0037] The induction units are 8 in number with exactly the same shape and size, evenly spaced and distributed on the surface of the rotor base body without contacting each other; the 8 induction units are symmetrically distributed in the 8 quadrants of the space rectangular coordinate system with the center of the rotor base body as the origin, the distances from the 8 induction units to the coordinate origin are equal, and the 8 induction units are spherically symmetrically distributed relative to the center of the sphere. The 8 induction units are located inside the sphere formed by the 6 excitation units, that is, the outer radius of the induction unit is less than the inner radius of the excitation unit.

[0038] Each excitation unit of the present invention is composed of a metal pole piece made of a conductive material, and the six metal pole pieces corresponding to the 6 excitation units are closely attached to the inner surface of the stator base body, that is, the outer surface radius of the excitation unit is equal to the inner surface radius of the stator base body. Similarly, each induction unit is composed of a metal pole piece made of a conductive material, and the eight metal pole pieces corresponding to the 8 induction units are closely attached to the outer surface of the rotor base body, that is, the inner surface radius of each induction unit is equal to the outer surface radius of the rotor base body.

[0039] Let the outer surface radius of the stator base body 1 be r S , and the thickness of the stator base body be d S , then the inner surface radius of the stator base body is r' S = r S - d S . The thickness of each excitation unit is d' S , then the inner surface radius of the excitation unit is r'' S＝ r' S - d' S . Let the angle size occupied by each excitation unit be θ S, the arc length of the excitation unit is w S = θ S × r S / 2. Since the center distance between two adjacent excitation units is 90°, the angle occupied by the interval at the closest position between two adjacent excitation units is δ S = π / 2 - θ S ; Let the angle occupied by each induction unit be θ R , then the angle occupied by the interval at the closest position between two adjacent induction units is δ R = π / 2 - θ R .

[0040] The rotor substrate 2 is a standard sphere with a hollow center. The hollow part is also a standard sphere. The radius of the hollow part, that is, the inner surface radius of the rotor substrate, is r'' R , the thickness of the rotor substrate is d' R , then the outer surface radius of the rotor substrate is r' R = r'' R + d' R . The thickness of each induction unit is d R , then the outer surface radius is r R = r' R + d R . The arc length of each induction unit is w R = θ R × r R / 2.

[0041] The outer contour shape of the excitation unit is preferably a spherical quadrilateral or a spherical circle, or a spherical annular structure formed by opening a corresponding quadrilateral hole or a circular hole at the center of the spherical quadrilateral or the spherical circle; the outer contour shape of the induction unit is a spherical triangle or a spherical circle, or a spherical annular structure formed by opening a circular hole at the center of the spherical triangle or the spherical circle.

[0042] For the structure with the excitation unit having a hollow center (i.e., a spherical annular structure formed by opening a corresponding quadrilateral hole or a circular hole at the center), there is an installation hole penetrating through the stator substrate. This installation hole is aligned with the hollow part of one of the excitation units, so that the surface of the rotor substrate communicates with the outside through this installation hole and the corresponding hollow part, thus facilitating the connection between the rotor and the external rotor drive turntable.

[0043] Embodiment 1: As shown in FIGS. 1 to 6, this embodiment is a spherical multi-dimensional rotation angle measurement time grating displacement sensor based on an alternating electric field. The stator substrate 1 and the rotor substrate 2 are concentrically installed with a spacing of d = 26 mm. The thickness d of the stator substrate S = 10 mm, the inner radius r' of the stator substrate S = 76 mm, and the thickness d' of the excitation unit provided on the inner surface of the stator substrate S = 2 mm. The thickness d' of the rotor substrateR = 40 mm, the outer radius r' of the rotor base R = 50 mm, the thickness d of the induction unit provided on the outer surface of the rotor base R = 2 mm.

[0044] As shown in FIGS. 2 and 5, six excitation units A, B, C, D, E, and F with exactly the same shape and size are provided on the inner surface of the stator base 1, and the angle occupied by a single excitation unit is θ S = π / 3, the gap δ between adjacent excitation units S = π / 2 - θ S = π / 6, and the six excitation units are concentrically installed.

[0045] The six excitation units are arranged at equal spatial angles around the Z-axis and around the X-axis respectively. The sinusoidal excitation signals applied to the four excitation units arranged in the rotational direction around the Z-axis are different, and the sinusoidal excitation signals applied to the four excitation units arranged in the rotational direction around the X-axis are different. The specific implementation method is as follows: The four excitation units A, B, C, and D arranged in the direction around the Z-axis are respectively applied with sinusoidal excitation signals Am*sin(ωt), Am*sin(ωt + π / 2), Am*sin(ωt + π), and Am*sin(ωt + 3π / 2). The four excitation units A, E, C, and F arranged in the direction around the X-axis are respectively applied with four sinusoidal excitation signals Am*sin(ωt), Am*sin(ωt + π / 2), Am*sin(ωt + π), and Am*sin(ωt + 3π / 2). Among them, the four excitation units arranged around the Z-axis and the four excitation units arranged around the X-axis share the excitation unit A and the excitation unit C. The four excitation units arranged around the Z-axis are respectively applied with four sinusoidal excitation signals with the same frequency and equal amplitude and a phase difference of 90°, forming an alternating electric field in space; the four excitation units arranged around the X-axis are respectively applied with four sinusoidal excitation signals with the same frequency and equal amplitude and a phase difference of 90°, forming an alternating electric field in space.

[0046] As shown in FIG. 3, eight induction units a, b, c, d, e, f, g, and h with exactly the same shape and size are provided on the outer surface of the rotor base 2. The shape of a single induction unit is a spherical triangle, and the angle occupied by a single induction unit is θ R = 5π / 12. The eight induction units are respectively located in the eight quadrants of the space rectangular coordinate system. The distances from the eight induction units to the coordinate origin are equal to the outer radius r' of the rotor base R = 50 mm, the eight induction units are located on the same spherical surface and do not touch each other, and the gap size between adjacent induction units is δ R = π / 2 - θ R = π / 12.

[0047] Coupling capacitances are formed between the eight induction units on the upper surface of the rotor substrate 2 and the six excitation units on the inner surface of the stator substrate 1. During measurement, four sinusoidal excitation signals with the same frequency and equal amplitude and a phase difference of π / 2 are sequentially applied to the six excitation units. A sinusoidal excitation signal of phase U A is applied to excitation unit A, and U A = Am*sin(ωt). Sinusoidal excitation signals of phase U B are applied to excitation units B and E, and U B = Am*sin(ωt + π / 2). A sinusoidal excitation signal of phase U C is applied to excitation unit C, and U C = Am*sin(ωt + π). Sinusoidal excitation signals of phase U D are applied to excitation units D and F, and U D = Am*sin(ωt + 3π / 2). The amplitude of the excitation signal A = 12V, the frequency f = 40kHz, and the angular frequency ω = 2πf = 8*10 4 π rad / s. When the rotor substrate 2 rotates relative to the stator substrate 1, eight sinusoidal induction signals Ua, Ub, Uc, Ud, Ue, Uf, Ug, Uh with the same frequency and equal amplitude are respectively generated by the a, b, c, d, e, f, g, h induction units through electric field coupling.

[0048] The signal processing method is shown in Figures 4 and 6. Ua, Ud, Ue, Uh and Ub, Uc, Uf, Ug are respectively summed through adders to obtain sine wave signals Uz+ and Uz- that only contain the angular displacement sine wave rotating around the Z axis; Ua, Ub, Uc, Ud and Ue, Uf, Ug, Uh are respectively summed through adders to obtain angular displacement signals Ux+ and Ux- that only contain the rotation around the X axis. Uz+ and Uz- are subtracted through a subtractor to obtain a sine wave signal Uz that only contains the angular displacement amount rotating around the Z axis; Ux+ and Ux- are subtracted through a subtractor to obtain a sine wave signal Ux that only contains the angular displacement amount rotating around the X axis. The expressions of the traveling wave signal Uz and the traveling wave signal Ux are as follows:

[0049] The traveling wave signal Uz that only contains the angular displacement amount rotating around the Z axis and the traveling wave signal Ux that only contains the angular displacement amount rotating around the X axis are formed into square waves through a shaping circuit and then sent into the FPGA for phase discrimination processing, and compared with a reference square wave U ref of the same frequency. The phase difference is represented by the number of high-frequency clock pulses interpolated, and after conversion, the rotational angular displacement α z of the rotor substrate 2 relative to the stator substrate 1 in the direction around the Z axis and the rotational angular displacement α x in the direction around the X axis are obtained.

[0050] Embodiment 2: The grid displacement sensor for measuring the spherical multi-dimensional rotation angle based on an alternating electric field in this embodiment has the same measurement principle and most of its structure as Embodiment 1. The difference is that as shown in Figure 7, the shape of the excitation unit is a spherical quadrilateral.

[0051] Embodiment 3: The grid displacement sensor for measuring the spherical multi-dimensional rotation angle based on an alternating electric field in this embodiment has the same measurement principle and most of its structure as Embodiment 1. The difference is that as shown in Figure 8, the shape of the excitation unit is a spherical quadrilateral with a hollow center, and the shape of the hollow part is a spherical quadrilateral.

[0052] Embodiment 4: The grid displacement sensor for measuring the spherical multi-dimensional rotation angle based on an alternating electric field in this embodiment has the same measurement principle and most of its structure as Embodiment 3. The difference is that as shown in Figure 9, the shape of the excitation unit is a spherical quadrilateral with a hollow center, and the shape of the hollow part is a spherical circle. Moreover, each excitation unit is composed of 4 metal pole pieces, forming a more uniform electric field. That is, the metal pole pieces Wa1, Wa2, Wa3, and Wa4 are connected by excitation signal leads to form excitation unit A; the metal pole pieces Wb1, Wb2, Wb3, and Wb4 are connected by excitation signal leads to form excitation unit B; the metal pole pieces Wc1, Wc2, Wc3, and Wc4 are connected by excitation signal leads to form excitation unit C; the metal pole pieces Wd1, Wd2, Wd3, and Wd4 are connected by excitation signal leads to form excitation unit D; the metal pole pieces We1, We2, We3, and We4 are connected by excitation signal leads to form excitation unit E; the metal pole pieces Wf1, Wf2, Wf3, and Wf4 are connected by excitation signal leads to form excitation unit F. In the same excitation unit, the gap between two adjacent metal pole pieces is δ' S = 1°.

[0053] Embodiment 5: The grid displacement sensor for measuring the spherical multi-dimensional rotation angle based on an alternating electric field in this embodiment has the same measurement principle and most of its structure as Embodiment 1. The difference is that as shown in Figure 10, each induction unit is composed of 6 metal pole pieces. Taking the induction unit a as an example, it is composed of metal pole pieces a1, a2, a3, a4, a5, and a6. The 6 metal pole pieces of each induction unit are connected together by wires. In the same induction unit, the gap between two adjacent metal pole pieces is δ' R = 1°.

[0054] Embodiment 6: The grid displacement sensor for measuring the spherical multi-dimensional rotation angle based on an alternating electric field in this embodiment has the same measurement principle and most of its structure as Embodiment 1. The difference is that as shown in Figure 11, the shape of each induction unit is a spherical circle, and the angle size occupied by each induction unit is θ R = 5π / 12.

[0055] Embodiment 7: The grid displacement sensor for measuring the spherical multi-dimensional rotation angle based on an alternating electric field in this embodiment has the same measurement principle and most of its structure as that in Embodiment 1. The difference lies in that as shown in Fig. 12, the shape of each induction unit is a spherical triangle with a hollow center, and the hollow part is a spherical circle.

[0056] Referring to Fig. 13, the present invention also provides an installation structure for the grid sensor for measuring the spherical multi-dimensional rotation angle. All the excitation units of the grid sensor for measuring the spherical multi-dimensional rotation angle are provided with hollow centers; a circular installation hole 3 that penetrates through the inside and outside is provided on the stator base 1, and this installation hole is aligned with the hollow part of one of the excitation units, so that the surface of the rotor base communicates with the outside through this installation hole and the corresponding hollow part. The stator base 1 is rotatably connected to the stator driving turntable through the stator support shaft 4, and the excitation electrode is connected to an external excitation source through a signal line penetrating the stator base housing; the rotor base 2 is rotatably connected to the rotor driving turntable through the rotor support shaft 5 and the rotor base is suspended inside the stator base; the signal line of the induction electrode is led out from the stator base through the rotor support shaft; the rotor support shaft 5 and the stator support shaft 4 are perpendicular to each other.

[0057] During actual installation, one end of the rotor support shaft is integrally formed with the surface of the rotor base and避开 the area where the induction units are located, and the other end of the rotor support shaft passes through the installation hole on the surface of the stator base and the corresponding hollow part in the middle and then is connected to the rotor driving turntable.

[0058] In order to facilitate the rotor support shaft to避开 the area where the induction units are located, all the induction units in the embodiment of the present invention are provided with hollow centers. One end of the rotor support shaft is integrally formed with the surface of the rotor base through the hollow area of one of the induction units, so as to避开 the area where the induction units are located. Of course, the rotor support shaft can also be connected to the rotor base in the gap area left by the four induction units at intervals.

[0059] One end of the stator support shaft of the present invention is integrally formed with the outer surface of the stator base, and the other end of the stator support shaft is connected to the stator driving turntable. The rotor support shaft of the present invention can rotate 360°, while the stator support shaft cannot. There is a rotational gap between the rotor support shaft and the installation hole on the surface of the stator base and the corresponding hollow part, and the rotation angle of the stator support shaft is limited by this rotational gap.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the applicant has described the present invention in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that any modification or equivalent replacement of the technical solutions of the present invention, without departing from the purpose and scope of the present technical solution, should be covered within the scope of the claims of the present invention.

Claims

1. A spherical multidimensional rotation angle measurement time grid sensor, comprising a stator base and a rotor base, wherein an excitation unit is disposed on the stator base and a sensing unit is disposed on the rotor base; characterized in that: The stator base is spherical, and the rotor base is spherical and located inside the spherical shell of the stator base. A gap is left between the surface of the rotor base and the inner surface of the stator base so that the rotor base is suspended and concentric with the stator base. The excitation unit consists of 6 identical shapes and sizes, evenly distributed on the inner surface of the stator base. The center of the 6 excitation units is located at the center of the six faces of a cube that is externally tangent to the inner surface of the stator base. The sensing units are eight identical in shape and size, evenly spaced on the surface of the rotor base; the eight sensing units are symmetrically distributed in the eight quadrants of a spatial rectangular coordinate system with the center of the rotor base as the origin.

2. The spherical multidimensional rotation angle measurement time grating sensor according to claim 1, characterized in that: Each excitation unit consists of a conductive metal electrode. The six metal electrodes corresponding to the six excitation units are tightly attached to the inner surface of the stator base. The outer surface radius of each excitation unit is equal to the inner surface radius of the stator base. Each sensing unit consists of a conductive metal electrode. The eight metal electrodes corresponding to the eight sensing units are tightly attached to the outer surface of the rotor substrate. The inner surface radius of each sensing unit is equal to the outer surface radius of the rotor substrate.

3. A spherical multidimensional rotation angle measurement grating sensor according to claim 1, characterized in that: The angle occupied by each excitation unit is θ. S The angle occupied by the interval between two adjacent excitation units is δ. S =π / 2-θ S ; The angle occupied by each sensing unit is θ. R The angle occupied by the interval between two adjacent sensing units is δ. R =π / 2-θ R .

4. A spherical multidimensional rotation angle measurement time grating sensor according to claim 1, characterized in that: The rotor base has a hollow center, and the hollow part is spherical.

5. A spherical multidimensional rotation angle measurement time grating sensor according to claim 1, characterized in that: The outer contour shape of the excitation unit is a spherical quadrilateral or a spherical circle, a spherical quadrilateral with a hollow center, or a spherical circle with a hollow center; the outer contour shape of the sensing unit is a spherical triangle or a spherical circle, or a spherical triangle or a spherical circle with a hollow center.

6. A spherical multidimensional rotation angle measurement grating sensor according to claim 1, characterized in that: All excitation units have a central cutout; the stator base has a through mounting hole that is directly opposite the cutout portion of one of the excitation units, so that the surface of the rotor base can communicate with the outside through the mounting hole and the corresponding cutout portion.

7. A mounting structure for a spherical multidimensional rotation angle measurement grating sensor, characterized in that: The spherical multidimensional rotation angle measurement time grid sensor is the spherical multidimensional rotation angle measurement time grid sensor as described in claim 6. The stator base is rotatably connected to the stator drive turntable via a stator support shaft. The excitation electrode is connected to an external excitation source via a signal line penetrating the stator base housing. The rotor base is rotatably connected to the rotor drive turntable via a rotor support shaft, and the rotor base is suspended within the stator base. The signal line of the sensing electrode is led out from the stator base via the rotor support shaft. The rotor support shaft and the stator support shaft are perpendicular to each other.

8. The mounting structure for a spherical multidimensional rotation angle measurement grating sensor according to claim 7, characterized in that: One end of the rotor support shaft is integrally formed with the surface of the rotor base and avoids the area where the sensing unit is located. The other end of the rotor support shaft passes through the mounting hole on the surface of the stator base and the hollow part corresponding to the mounting hole, and then connects to the rotor drive turntable.

9. The mounting structure for a spherical multidimensional rotation angle measurement grating sensor according to claim 8, characterized in that: All sensing units have a hollowed-out center, and one end of the rotor support shaft is integrally formed with the rotor base surface through the hollowed-out area of ​​one of the sensing units, thereby avoiding the area where the sensing unit is located.

10. A grating sensor mounting structure for spherical multidimensional rotation angle measurement according to claim 8 or 9, characterized in that: One end of the stator support shaft is integrally formed with the outer surface of the stator substrate, and the other end of the stator support shaft is connected to the stator drive turntable; There is a rotational clearance between the rotor support shaft and the mounting hole on the surface of the stator base and the corresponding hollow part, and the rotation angle of the stator support shaft is limited by the rotational clearance.

Images