CN103527620B - Spherical hinge and the method for measurement of angle of revolution measurement can be realized - Google Patents

Abstract

The invention discloses a kind of spherical hinge and the method for measurement that realize angle of revolution measurement, it is characterized in that: form by base and end cap the ball seat that inside has ball-and-socket, bulb is inserted in ball-and-socket, and exposes spherical crown at the opening of end cap, connects ball pivot bar at the spherical crown end face of bulb; Bulb and ball-and-socket are concentric, and bulb can rotate with one heart relative to ball-and-socket; Be embedded with permanent magnet on the lower semisphere surface of bulb, each permanent magnet is evenly distributed on the lower semisphere surface of bulb; Be embedded with magnetic effect sensor on the surface of ball-and-socket, each magnetic effect sensor is evenly distributed on the surface of ball-and-socket; The induction of magnetic effect sensor is utilized to output signal the direction judging relative position between bulb and ball-and-socket and relative movement.The present invention is not affecting ball-joint kinematic accuracy, mechanical property, under not destroying the prerequisite of its structure, realizes three-dimensional perspective and measures.

Description

Spherical hinge and the method for measurement of angle of revolution measurement can be realized

Technical field

The present invention relates to a kind of spherical hinge, be more particularly can angle of revolution, implementation space measure spherical hinge and method of measurement.

Background technique

Angle measurement is the most basic measurement, and in prior art, existing various angle transducer extensive use, comprising: grating, magnetic grid, inductosyn etc., but this kind of sensor all can only carry out the measurement of one dimension angle of revolution.In scientific research and industrial production, the way that multiple angle transducer can only be adopted to combinationally use when needing the angle of revolution measuring multiple directions.Such as in fine measuring instrument, joint arm measuring machine, laser tracker and precision digital turntable etc.These combination complex structures of angle measurement component, cost are high, equipment volume is large, subsequent conditioning circuit and data collection task amount large, application is subject to great restriction; Traditional angle transducer is all adopt equidistant groove on the disk or cylndrical surface of certain turning radius to realize measuring, its measuring accuracy relies on graduating accuracy in essence, subdivide technology can only be adopted compensated when precision is not enough, this fundamentally limits the further lifting of sensor accuracy, also reduces stability.

Recent two decades is widely used in fields such as lathe, robot, micro displacement workbench, coordinate measuring machines because paralleling mechanism has the advantages such as light, the natural error average effect of good rigidity, movement inertia.But in paralleling mechanism, the movement clearance error of a large amount of spherical hinge of using and ball-joint seriously constrains paralleling mechanism in the application of highi degree of accuracy occasion and popularization all the time, and spherical hinge is drive it to move by other motion and power source when using on paralleling mechanism, dawn cannot be obtained in real time in the angle of revolution in space of ball pivot bar.

Japanese river of rubbing proposes the pattern printing similar Quick Response Code on spherical hinge spheroid more, image recognition is carried out with ccd video camera, then compare according to the standard pattern relevant to the absolute angle in three coordinate axes of spheroid and calculate, drawing angle information (ZL200780043541.0).It this technological essence is the measuring method based on Machine vision, need to add lubricating ester to alleviate the friction between ball pivot bar and ball-and-socket during spherical hinge actual motion work, the existence of lubricating grease has a strong impact on quality of optical imaging, and is difficult to reduce in physical dimension and cannot be embedded into spherical hinge inside.

Zahnradfabrik Friedrichshafen of Germany proposes the ball-type universal joint with pivot angle sensor, the object of research and development is used on automobile chassis for detecting the distortion on chassis and the distortion in moving, basic principle embeds a permanent magnet magnet in the bottom of hinge spheroid, ball-and-socket embeds magnetoresistive transducer and is used for the swing of perception club and spheroid, this magnetoresistive transducer directly can obtain the direct value of the angle of the magnetic line of force through sensor, the method carries out sensing by magnetic effect, overcome the impact of lubricating grease, require also not harsh to Environmental Conditions, but only realize combination with a sensor and a permanent magnet, thus the scope that takes measurement of an angle inevitably is produced little, the defect that measuring accuracy is lower, the required precision of paralleling mechanism when highi degree of accuracy applications and range cannot be met.

Summary of the invention

The present invention is the deficiency for avoiding existing for above-mentioned prior art, there is provided a kind of realize wide range, high-precision angle of revolution measure spherical hinge and method of measurement, do not affecting ball-joint kinematic accuracy, mechanical property, under not destroying the prerequisite of its structure, realizing three-dimensional perspective and measure.

The present invention is that technical solution problem adopts following technological scheme:

The structural feature that the present invention can realize the spherical hinge that angle of revolution is measured is:

Form by base and end cap the ball seat that inside has ball-and-socket, the spherical crown portion of described ball-and-socket is formed as opening on end cap; Bulb is inserted in described ball-and-socket, and exposes spherical crown at the opening of end cap, connects ball pivot bar at the spherical crown end face of described bulb; Described bulb and ball-and-socket are concentric, and bulb can rotate with one heart relative to ball-and-socket;

Be embedded with permanent magnet on the lower semisphere surface of described bulb, and have m permanent magnet to be evenly distributed on the lower semisphere surface of described bulb; Be embedded with magnetic effect sensor on the surface of described ball-and-socket, and have n magnetic effect sensor to be evenly distributed on the surface of ball-and-socket; Wherein, n and m is all non-vanishing; The induction of described magnetic effect sensor is utilized to output signal the direction judging relative angular position between described bulb and ball-and-socket and relative movement.

The structural feature that the present invention can realize the spherical hinge that angle of revolution is measured also is: described permanent magnet cylindrical body, and is sleeved in the spacer be made up of nonmagnetic substance, and the related permanent magnet of described spacer is embedded in each blind cylindrical hole of bulb surface setting; The axis of described each permanent magnet is all through the centre of sphere of bulb.

Described bulb and ball pivot bar take ferromagnetic material as material.

Described each magnetic effect sensor is embedded in each gauge hole of described ball-and-socket surface setting, and on the sphere that each magnetic effect sensor is in centered by ball-and-socket center together, radius is R, the axis of each magnetic effect sensor is through ball-and-socket center; Arranging each gauge hole is step hole, and magnetic effect sensor is glued on the sensor holder that non-magnetic material makes, and described sensor holder related magnetic effect sensor is inlaid in described step hole.

The feature utilizing spherical hinge in the present invention to realize the method that angle of revolution is measured is: the revolution of going up in any direction around centre of sphere O for spherical hinge, the magnetic field that permanent magnet produces is rotated thereupon, calculate the magnetic induction intensity of spatial position, magnetic effect sensor place according to Equivalent Magnetic Charge model, draw the relation between the magnetic induction intensity component in magnetic effect sensor axis direction and spherical hinge angle of revolution; According to the input-output characteristic of magnetic effect sensor, set up the voltage output signal of each magnetic effect sensor and the function relation of spherical hinge angle of revolution; The function relation of each magnetic effect sensor of simultaneous sets up set of equation, utilizes method of least squares to realize solving of set of equation, draws spherical hinge angle of revolution.

Present inventor finds under study for action: in paralleling mechanism, spherical hinge gap is relevant with pose to ball pivot bar working space angle in essence, if the space rotating accuracy of Real-time Obtaining spherical hinge has important meaning and value for revising and compensate spherical hinge gap error and even improving paralleling mechanism kinematic accuracy.Namely the present invention is the intellectuality for realizing spherical hinge, and its structure is simple, reliable performance, can be applicable to Conventional robotic and to control and other has the occasion in multi-dimensional movement joint to realize the real-time measurement of its space angle.

Compared with the prior art, beneficial effect of the present invention is embodied in:

1, present invention achieves three-dimensional perspective to detect, also can be applied to engineering reality as independently surveying.

2, the present invention equidistantly divides the form obtaining angle measurement information compared to traditional space, redundancy angle information is obtained by the measurement in a closed series of multiple magnetic effect sensor, resolution and measuring accuracy can be improved, permanent magnet number can be configured according to actual needs with also range extension simultaneously.

3, traditional vernier reading is the method for a kind of mechanical type segmentation reading, and this principle of measurement is applied on sphere by the present invention, determines and optimize the number of permanent magnet and sensor chip and the space arrangement spacing on sphere with this.

4, the present invention adopts magnetic effect to carry out sensing, and when effectively overcoming spherical hinge actual use, outside environmental elements is on the interference of measuring accuracy and impact, and insensitive on the impact of lubricating grease.

5, structure of the present invention is simple, compact, and cost is low, also can make independent parts, the joint being directly configured in existing device realizes the measurement of any direction angle of revolution in its space, has larger application and popularization value.

Accompanying drawing explanation

Fig. 1 is the main TV structure schematic diagram of the present invention;

Fig. 2 is structural upright exploded perspective view of the present invention;

Fig. 3 is permanent magnet and magnetic effect sensor fitting structure schematic diagram in the present invention;

Fig. 4 cylindrical permanent magnet body Equivalent Magnetic Charge model schematic;

Fig. 5 is principle of measurement schematic diagram in the present invention;

Number in the figure: 1 base; 2 ball pivot bars; 3 bulbs; 4 permanent magnets; 5 magnetic effect sensors; 6 end caps; 7 bolt semiaxis; 8 spacers; 9 sensor holders.

Embodiment

See Fig. 1, Fig. 2 and Fig. 3, the structural type that can realize the spherical hinge that angle of revolution is measured in the present embodiment is:

Form by base 1 and end cap 6 ball seat that inside has ball-and-socket, the spherical crown portion of ball-and-socket is formed as opening on end cap 6; Bulb 3 is inserted in ball-and-socket, and exposes spherical crown at the opening of end cap 6, connects ball pivot bar 2 at the spherical crown end face of bulb 3; Bulb 3 and ball-and-socket are concentric, and bulb 3 can rotate with one heart relative to ball-and-socket.

Be embedded with permanent magnet 4 on the lower semisphere surface of bulb 3, and have m permanent magnet 4 to be evenly distributed on the lower semisphere surface of bulb 3; Be embedded with magnetic effect sensor 5 on the surface of ball-and-socket, and have n magnetic effect sensor 5 to be evenly distributed on the surface of ball-and-socket; Wherein, n and m is all non-vanishing; The induction of magnetic effect sensor 5 is utilized to output signal the direction judging relative angular position between bulb 3 and ball-and-socket and relative movement.

As shown in Figures 2 and 3, permanent magnet 4 is cylindrical body, and is sleeved in the spacer 8 be made up of nonmagnetic substance, and the related permanent magnet of spacer 84 is embedded in each blind cylindrical hole of bulb surface setting; The axis of each permanent magnet 4 is all through the centre of sphere of bulb 3; Bulb and ball pivot bar take ferromagnetic material as material.

Each magnetic effect sensor 5 is embedded in each gauge hole of ball-and-socket surface setting, and on the sphere that each magnetic effect sensor 5 is in centered by ball-and-socket center together, radius is R, the axis of each magnetic effect sensor 5 is through ball-and-socket center; Arranging each gauge hole is step hole, and magnetic effect sensor is glued on the sensor holder 9 that non-magnetic material makes, and the related magnetic effect sensor of sensor holder 9 is inlaid in step hole.

Ball pivot bar 2 and spherical journal 3 are formed through Overheating Treatment and precision cutting process by steel, it is ferromagnetic material, when permanent magnet 4 is embedded in spherical journal, its magnetic pole contacts with spherical journal 3, jointly on spheroid and around form the closed magnetic line of force and the magnetic field in given shape and space.Permanent magnet should select the magnetic material manufacture of high-quality, and alnico alloy 500 or barium ferrite or analog material can be selected to make.

Magnetic effect sensor according to the difference of measuring accuracy and range, can select Hall transducer and magnetic resistance and giant magneto-resistance sensor etc.

The method utilizing spherical hinge in the present embodiment to realize measuring angle of revolution is: the revolution of going up in any direction around centre of sphere O for spherical hinge, the magnetic field that permanent magnet produces is rotated thereupon, calculate the magnetic induction intensity of spatial position, magnetic effect sensor place according to Equivalent Magnetic Charge model, draw the relation between the magnetic induction intensity component in magnetic effect sensor axis direction and spherical hinge angle of revolution; According to the input-output characteristic of magnetic effect sensor, set up the voltage output signal of each magnetic effect sensor and the function relation of spherical hinge angle of revolution; The function relation of each magnetic effect sensor of simultaneous sets up set of equation, utilizes method of least squares to realize solving of set of equation, draws spherical hinge angle of revolution.In concrete enforcement, carry out as follows:

First set up measurement model, its theoretical foundation is Equivalent Magnetic Charge model.For the cylinder permanent magnet evenly magnetized vertically, owing to being uniform magnetization, body magnetic charge density ρ _mbe zero, permanent magnet border exists surface magnet charge density σ _m, and have following relation:

In formula (1) for the exterior normal unit vector of permanent magnet interface;

B _rfor the residual magnetic flux density of permanent magnet.According to the concept of scalar magnetic potential, the magnetic intensity that cylinder permanent magnet produces in any point of space be expressed as with the form of Line Integral:

$\stackrel{\→}{H}=\frac{B_r}{4\mathrm{\π}{\mathrm{\μ}}_0}\underset{s_{+}}{\∫\∫}\frac{{\stackrel{\→}{r}}_{+}}{{r_{+}}^3}\mathrm{ds}-\frac{B_r}{4\mathrm{\π}{\mathrm{\μ}}_0}\underset{s_{-}}{\∫\∫}\frac{{\stackrel{\→}{r}}_{-}}{{r_{-}}^3}\mathrm{ds}---\left(2\right)$

Magnetic induction intensity with magnetic intensity relation be:

$\stackrel{\→}{B}={\mathrm{\μ}}_0{\mathrm{\μ}}_r\stackrel{\→}{H}---\left(3\right)$

In formula (2) and formula (3): μ _rfor the relative permeability of Magnetized Material, μ ₀for the permeability in vacuum, r ₊, r _-source point for positive and negative magnetic charge is shown up distance a little, S ₊, S _-for the source area of positive and negative magnetic charge.

Equivalent Magnetic Charge model uses integration to try to achieve the magnetic intensity that permanent magnet produces in any point of space, then be converted to magnetic induction intensity.As shown in Figure 5, when spherical hinge around centre of sphere O in any direction upper rotary time, being embedded in the magnetic field that the permanent magnet on bulb produces will rotate thereupon, and the magnetic induction intensity of any point in space is changed.With spherical hinge gyration center for initial point O, with perpendicular to base upwards for Z-direction, set up basis coordinates system O-XYZ; For the position that ball pivot bar rotates arbitrarily in space, can be decomposed into and first turn α angle around X-axis, β angle is turned again around Y-axis, after ball pivot bar rotates, the position of permanent magnet moves on to M ' point by original M point, sets up kinetic coordinate system O-X ' Y ' Z ' according to the mode setting up basis coordinates system O-XYZ for the position after rotation.

Magnetic effect sensor is arranged in ball-and-socket inner ball surface, and as shown in Figure 5, there are four magnetic effect sensors position shown in Fig. 5, and its measuring surface center line is all orthogonal at centre of sphere O place, for one of them sensor, and setting sensor S ₁coordinate in basis coordinates system O-XYZ is (x ₀, y ₀, z ₀), its measuring surface normal is through centre of sphere O fixed directional Z " direction.

In kinetic coordinate system O-X ' Y ' Z ', according to Formula of Coordinate System Transformation, sensor S ₁coordinate is expressed as:

$\left\{\begin{array}{c}u=x_0\cos \mathrm{\β}+y_0\sin \mathrm{\α}\sin \mathrm{\β}-z_0\cos \mathrm{\α}\sin \mathrm{\β}\\ v=y_0\cos \mathrm{\α}+z_0\sin \mathrm{\α}\\ w=x_0\sin \mathrm{\β}-y_0\sin \mathrm{\α}\cos \mathrm{\β}+z_0\cos \mathrm{\α}\cos \mathrm{\β}\end{array}\right.$

Carrying out the major significance that coordinate rotates change is in kinetic coordinate system O-X ' Y ' Z ', and solve integration according to Equivalent Magnetic Charge model theory convenient, if in basis coordinates system O-XYZ, it is then more difficult to carry out Integration Solving.After permanent magnet turns to M ' position with ball pivot bar, sensor S ₁the magnetic induction intensity at place will change, and sensor S ₁the Three-Dimensional Magnetic induction component (B of magnetic induction intensity under O-X ' Y ' Z ' coordinate at place _x', B _y', B _z') be expressed as respectively according to formula (2) and formula (3):

$\begin{array}{c}{B_x}^{\text{'}}=\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}{\∫}_{-r}^r[{(u-\sqrt{r^2-y^{\text{'}2}})}^2+{(v-y^{\text{'}})}^2+{(w-a)}^2{]}^{-\frac{1}{2}}{\mathrm{dy}}^{\text{'}}-\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}{\∫}_{-r}^r{[{(u+\sqrt{r^2-y^{\text{'}2}})}^2+{(v-y^{\text{'}})}^2+{(w-a)}^2]}^{-\frac{1}{2}}{\mathrm{dy}}^{\text{'}}\\ -\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}{\∫}_{-r}^r{[{(u-\sqrt{r^2-y^{\text{'}2}})}^2+{(v-y^{\text{'}})}^2+{(w-b)}^2]}^{-\frac{1}{2}}{\mathrm{dy}}^{\text{'}}+\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}{\∫}_{-r}^r{[{(u+\sqrt{r^2-y^{\text{'}2}})}^2+{(v-y^{\text{'}})}^2+{(w-b)}^2]}^{-\frac{1}{2}}{\mathrm{dy}}^{\text{'}}\end{array}$

$\begin{array}{c}{B_y}^{\text{'}}=\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}{\∫}_{-r}^r{[{(u-x^{\text{'}})}^2+{(v-\sqrt{r^2-x^{\text{'}2}})}^2+{(w-a)}^2]}^{-\frac{1}{2}}{\mathrm{dx}}^{\text{'}}-\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}{\∫}_{-r}^r{[{(u-x^{\text{'}})}^2+{(v+\sqrt{r^2-x^{\text{'}2}})}^2+{(w-a)}^2]}^{-\frac{1}{2}}{\mathrm{dx}}^{\text{'}}\\ -\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}{\∫}_{-r}^r{[{(u-x^{\text{'}})}^2+{(v-\sqrt{r^2-x^{\text{'}2}})}^2+{(w-b)}^2]}^{-\frac{1}{2}}{\mathrm{dx}}^{\text{'}}+\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}{\∫}_{-r}^r{[{(u-x^{\text{'}})}^2+{(v+\sqrt{r^2-x^{\text{'}2}})}^2+{(w-b)}^2]}^{-\frac{1}{2}}{\mathrm{dx}}^{\text{'}}\end{array}$

$\begin{array}{c}{B_z}^{\text{'}}=\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}\underset{-r}{\overset{r}{\∫}}\frac{w-a}{{(v-y^{\text{'}})}^2+{(w-a)}^2}\×\frac{u+\sqrt{r^2-y^{\text{'}2}}}{\sqrt{{(u+\sqrt{r^2-y^{\text{'}2}})}^2+{(v-y^{\text{'}})}^2+{(w-a)}^2}}{\mathrm{dy}}^{\text{'}}\\ -\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}\underset{-r}{\overset{r}{\∫}}\frac{w-a}{{(v-y^{\text{'}})}^2+{(w-a)}^2}\×\frac{u-\sqrt{r^2-y^{\text{'}2}}}{\sqrt{{(u+\sqrt{r^2-y^{\text{'}2}})}^2+{(v-y^{\text{'}})}^2+{(w-a)}^2}}{\mathrm{dy}}^{\text{'}}\\ -\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}\underset{-r}{\overset{r}{\∫}}\frac{w-b}{{(v-y^{\text{'}})}^2+{(w-b)}^2}\×\frac{u+\sqrt{r^2-y^{\text{'}2}}}{\sqrt{{(u+\sqrt{r^2-y^{\text{'}2}})}^2+{(v-y^{\text{'}})}^2+{(w-b)}^2}}{\mathrm{dy}}^{\text{'}}\\ +\frac{B_r{\mathrm{\μ}}_r}{4\mathrm{\π}}\underset{-r}{\overset{r}{\∫}}\frac{w-b}{{(v-y^{\text{'}})}^2+{(w-b)}^2}\×\frac{u-\sqrt{r^2-y^{\text{'}2}}}{\sqrt{{(u-\sqrt{r^2-y^{\text{'}2}})}^2+{(v-y^{\text{'}})}^2+{(w-b)}^2}}{\mathrm{dy}}^{\text{'}}\end{array}$

In formula: u, v, w are sensor S ₁coordinate in kinetic coordinate system O-X ' Y ' Z '; R is the radius of permanent magnet, is definite value, and a is the distance of permanent magnet upper-end surface to coordinate center O point, and b is the distance of permanent magnet lower end surface to coordinate center O point, x ', y ' and, z ' is integration variable.

Calculating above on kinetic coordinate system O-X ' Y ' Z ' definite integral form is expressed, only relevant with every magnetic parameter of permanent magnet and size, irrelevant with corner α, β of ball pivot bar.Sensor S ₁can the direction of magnetic induction intensity of perception be the Normal direction of its measuring surface, be determined by the mounting point of sensor and angle, namely fixing Z " direction;

Utilize sensor S ₁three-dimensional component (the B of magnetic induction intensity under kinetic coordinate system O-X ' Y ' Z ' at place _x', B _y', B _z') convert as follows and calculate acquisition sensor S ₁the magnetic induction intensity at place is at Z " component on direction:

Step 1: by sensor S ₁three-dimensional component (the B of magnetic induction intensity under kinetic coordinate system O-X ' Y ' Z ' at place _x', B _y', B _z') conversion obtain the three-dimensional component (B under O-XYZ system of coordinates _x, B _y, B _z):

$\left\{\begin{array}{c}{B}_x={B_x}^{\text{'}}\cos \mathrm{\β}+{B_z}^{\text{'}}\sin \mathrm{\β}\\ B_y={B_x}^{\text{'}}\sin \mathrm{\α}\sin \mathrm{\β}+{B_y}^{\text{'}}\cos \mathrm{\α}-{B_z}^{\text{'}}\sin \mathrm{\α}\cos \mathrm{\β}\\ B_z=-{B_x}^{\text{'}}\cos \mathrm{\α}\sin \mathrm{\β}+{B_y}^{\text{'}}\sin \mathrm{\α}+{B_z}^{\text{'}}\cos \mathrm{\α}\cos \mathrm{\β}\end{array}\right.$

Step 2: the fixed-direction Z of sensor sensing " is equivalent to basis coordinates system O-XYZ and first turns over α around X-axis ₀angle, then turn over β around Y-axis ₀z axis direction behind angle;

By the magnetic induction intensity component (B under O-XYZ coordinate _x, B _y, B _z) be expressed as at O-XYZ the component B in " component under system of coordinates, wherein Z " direction _z' ' be expressed as:

B _z''=B _xsinβ ₀-B _ysinα ₀cosβ ₀+B _zcosα ₀cosβ ₀

" namely direction is the direction of sensor sensing to Z;

According to the input-output characteristic of magnetic effect sensor, no matter be select magnetoresistive transducer or Hall transducer, all can setting voltage output signal U and magnetic induction intensity component B _z" between pass be:

k in formula _ifor each rank coefficient, determined by the characteristic of each sensor;

Through above-mentioned integral and calculating and Coordinate Conversion, known each sensor voltage output signal U _iby relevant to angle of revolution α and β of ball pivot bar, U can be expressed as _i=f (α, β), mathematically, only need place two sensors, set up following Simultaneous Equations, can solve two unknown number α and β, be measurement result in magnetic field:

U ₁=f ₁(α,β)

U ₂=f ₂(α,β)

In concrete enforcement, be utilize computer-implemented signals collecting and data processing for measurement model, to obtain measurement result.

The present invention uses many sensors to measure simultaneously, there is information redundancy in reading, in set of equation, equation number is more than unknown number number, the methods such as least square are utilized to realize Solving Nonlinear Systems of Equations, this is a kind of average weighted means in essence, reduce measurement error, improve the reliability that resolution also improves system.Simultaneously, the scheme adopting many permanent magnets uniform not only can range extension, by rationally determining the difference of spacing between spacing and magnetic effect sensor between permanent magnet, is conducive to improving resolution, this is a kind of method of machinery segmentation, similar to the counting principle of vernier calliper.

For there being multidimensional rotation motion demand, and need the occasion measuring its multidimensional angle of revolution, the present invention all can apply.Such as wrist power robot, multi-freedom joint robot and joint coordinates measuring machine, precise rotating platform.On Large-Scale Equipment, need to measure its angle during boats and ships propeller Solid rocket engine, helicopter screw propeller controlling party to time also need to measure its aerial pose angle, also need when solar energy sailboard is opened on astrovehicle to detect its expanded angle and direction, even on vehicle front course changing control, also need similar angle transducer.

Claims (4)

1. utilize spherical hinge to realize a method for angle of revolution measurement, described spherical hinge refers to the spherical hinge that can realize angle of revolution and measure, and the structural type of described spherical hinge is:

Form the inner ball seat with ball-and-socket by base (1) and end cap (6), the spherical crown portion of described ball-and-socket is formed as opening on end cap (6); Bulb (3) is inserted in described ball-and-socket, and exposes spherical crown at the opening of end cap (6), connects ball pivot bar (2) at the spherical crown end face of described bulb (3); Described bulb (3) and ball-and-socket are concentric, and bulb (3) can rotate with one heart relative to ball-and-socket; Be embedded with permanent magnet (4) on the lower semisphere surface of described bulb (3), and have m permanent magnet (4) to be evenly distributed on the lower semisphere surface of described bulb (3); Be embedded with magnetic effect sensor (5) on the surface of described ball-and-socket, and have n magnetic effect sensor (5) to be evenly distributed on the surface of ball-and-socket; Wherein, n and m is all non-vanishing; The induction of described magnetic effect sensor (5) is utilized to output signal the direction judging relative angular position between described bulb (3) and ball-and-socket and relative movement;

It is characterized in that: the described method utilizing spherical hinge to realize measuring angle of revolution is:

For the revolution that spherical hinge is gone up in any direction around centre of sphere O, the magnetic field that permanent magnet produces is rotated thereupon, calculate the magnetic induction intensity of spatial position, magnetic effect sensor place according to Equivalent Magnetic Charge model, draw the relation between the magnetic induction intensity component in magnetic effect sensor axis direction and spherical hinge angle of revolution; According to the input-output characteristic of magnetic effect sensor, set up the voltage output signal of each magnetic effect sensor and the function relation of spherical hinge angle of revolution; The function relation of each magnetic effect sensor of simultaneous sets up set of equation, utilizes method of least squares to realize solving of set of equation, draws spherical hinge angle of revolution.

2. the method utilizing spherical hinge to realize angle of revolution measurement according to claim 1, it is characterized in that: in described spherical hinge, permanent magnet (4) is cylindrical body, and being sleeved in the spacer (8) be made up of nonmagnetic substance, described spacer (8) related permanent magnet (4) is embedded in each blind cylindrical hole of bulb surface setting; The axis of described permanent magnet (4) passes the centre of sphere of bulb (3).

3. the method utilizing spherical hinge to realize angle of revolution measurement according to claim 1, is characterized in that: in described spherical hinge, bulb and ball pivot bar take ferromagnetic material as material.

4. the method utilizing spherical hinge to realize angle of revolution measurement according to claim 1, it is characterized in that: in described spherical hinge, magnetic effect sensor (5) is embedded in the gauge hole of described ball-and-socket surface setting, on the sphere that magnetic effect sensor (5) is in centered by ball-and-socket center, radius is R, the axis of magnetic effect sensor (5) is through ball-and-socket center; Arranging gauge hole is step hole, and magnetic effect sensor is glued on the sensor holder (9) that non-magnetic material makes, and described sensor holder (9) related magnetic effect sensor is inlaid in described step hole.