CN112197698B - A method and system for measuring the axis of rotation cone angle amplification servo axis - Google Patents

Abstract

The invention discloses a method and a system for measuring a rotary cone angle amplification servo axis, wherein the method comprises the following steps: the target disc is magnetically attracted to the end faces of the servo inner ring bearing and the servo outer ring bearing; rotating the servo inner ring and the servo outer ring, and acquiring a plurality of spatial positions of the mark points rotating around the bearing through a binocular vision system; inputting the plurality of spatial positions into a computer to fit a revolution axis; and measuring normal vectors of a certain plane fixed on the shaft at a plurality of moments in the rotating process based on the revolution axis so as to fit the revolution center line vector of the conical surface. The invention has the advantages that: the realization is simple, and the device comprises a target disc which is used for being magnetically adsorbed on the end surfaces of the servo inner ring bearing and the servo outer ring bearing; the binocular vision system is used for collecting a plurality of spatial positions of the mark points rotating around the bearing when the inner and outer servo rings are rotated; and the processing module is used for fitting the conical surface rotation center line vector, realizing non-contact measurement of the virtual rotating shaft and solving the problem that the servo virtual rotating shaft cannot be directly measured.

Description

A method and system for measuring the axis of rotation cone angle amplification servo axis

technical field

The invention belongs to the fields of precision measurement and precision adjustment, and in particular relates to a method and a system for measuring a rotary taper angle amplifying servo axis.

Background technique

When the servo mechanism is assembled, it is often necessary to measure the spatial direction of the rotary shafts such as the inner ring and the outer ring. The rotary shaft is a virtual feature formed by the dynamic rotation of the bearings at both ends of the inner and outer rings, which cannot be directly obtained by simple means such as measuring tools. The size of the bearing end face is very small. If you want to arrange marking points on it, it will be very concentrated and the number of marking points will be small, and the axis fitting error will be large. The existing technical means are generally complex, cannot directly measure the virtual rotary axis of the servo, and cannot be well applied to the measurement of the spatial angle of the virtual rotary axis of the servo mechanism.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a method for measuring the servo axis by amplifying the rotary cone angle, which solves the problem that the servo virtual rotary axis cannot be directly measured.

In view of this, the technical solution provided by the present invention is: a method for measuring the servo axis of the rotary cone angle amplification, which is characterized in that, comprising:

First, the target disk is magnetically attached to the end faces of the inner and outer ring bearings of the servo;

Secondly, rotate the inner and outer rings of the servo, and collect multiple spatial positions of the marking points rotating around the bearing through the binocular vision system;

Then, inputting the computer to fit the axis of rotation according to the plurality of spatial positions;

Finally, the normal vectors of a certain plane fixed on the shaft at multiple times during the rotation process are measured based on the rotation axis, so as to fit the centerline vector of the rotation of the cone surface.

Further, the target disk is magnetically adsorbed on the end faces of the inner and outer ring bearings of the servo at a 5-15° angle.

Further, the binocular vision system acquires multiple spatial positions of the marked points rotating around the bearing, including: using the binocular vision system to acquire the image of the target disk during one rotation of the shaft at a constant speed.

Further, inputting the computer to fit the axis of rotation includes: fitting the normal vector of the target disk at each moment in the computer.

Further, measuring the normal vectors of a certain plane fixed on the shaft at multiple moments during the rotation process to fit the centerline vector of the cone surface rotation, including: by fitting the cone surface composed of the target disk normal vectors at multiple times The center line of revolution of , obtains the direction vector of the axis to be measured.

Further, fitting the normal vector of the target disk at each moment in the computer includes: using the image processing technology to perform edge extraction in the computer, and then identifying all the marked points in the image through the feature recognition algorithm.

Further, the feature recognition algorithm is an ellipse recognition algorithm.

Another object of the present invention is to provide a rotary cone angle amplification servo axis measurement system, characterized in that it includes:

The target plate is used for certain magnetic adsorption on the end faces of the inner and outer ring bearings of the servo;

The binocular vision system is used to collect multiple spatial positions of the marked points rotating around the bearing when the inner and outer rings of the servo are rotated;

The processing module is used for inputting the computer to fit the rotation axis according to the plurality of spatial positions, and measuring the normal vector of a certain plane fixed on the shaft at multiple moments during the rotation process based on the rotation axis, so as to fit the cone surface The centerline vector of gyration.

Further, on the surface of the circular galvanized thin iron sheet, a plurality of marking points are randomly and uniformly arranged on the surface.

Further, the target disk is a circular galvanized iron sheet with a diameter of 80 mm, and the surface of the target disk is randomly and evenly distributed with 5 mm marking points, and the distribution range is more than 60 mm.

The present invention achieves the following significant beneficial effects

The implementation is simple, including: magnetically attaching the target disk to the end faces of the inner and outer rings of the servo; rotating the inner and outer rings of the servo, and collecting multiple spatial positions of the marked points rotating around the bearing through a binocular vision system; The multiple spatial positions are input into the computer to fit the rotation axis; based on the rotation axis, the normal vectors of a certain plane fixed on the shaft at multiple times during the rotation process are measured to fit the cone surface rotation centerline vector. It can achieve the effect of non-contact measurement technology of virtual rotary axis based on binocular vision, and solve the problem that servo virtual rotary axis cannot be directly measured.

Description of drawings

FIG. 1 is a flow chart of a method for measuring a rotary cone angle amplification servo axis according to the present invention.

Fig. 2 is the target disk schematic diagram of the present invention;

FIG. 3 is a schematic diagram of the taper fitting principle of the present invention.

FIG. 4 is a flow chart of an embodiment of a method for measuring a rotary cone angle amplification servo axis according to the present invention.

reference numerals

1. Marking point 2. Target plate 3. The cone formed by the rotation of the normal vector of the target plate around the axis to be measured

4. The direction vector of the axis to be measured

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages and characteristics of the present invention will be more clearly understood from the following description and claims. It should be noted that, the accompanying drawings are all in a very simplified form and are all applied to inaccurate scales, and are only used to facilitate and clearly assist the purpose of explaining the embodiments of the present invention.

It should be noted that, in order to clearly illustrate the content of the present invention, the present invention provides multiple embodiments to further illustrate different implementations of the present invention, wherein the multiple embodiments are enumerated rather than exhaustive. In addition, for the sake of brevity of description, the content mentioned in the previous embodiment is often omitted in the latter embodiment, and therefore, the content not mentioned in the latter embodiment may refer to the former embodiment accordingly.

Although the invention can be expanded in various forms of modification and substitution, some specific embodiments are also listed and described in detail in the specification. It should be understood that the inventor's intent is not to limit the invention to the particular embodiments set forth, but on the contrary, the inventor's intent is to protect all improvements, equivalent substitutions, and modifications that come within the spirit or scope defined by this statement of claims . The same element part numbers may be used throughout the drawings to represent the same or similar parts.

Please refer to FIG. 1 to FIG. 4 , a method for measuring the servo axis of amplifying the rotation cone angle of the present invention includes:

Step S101, the target disk is magnetically adsorbed on the end faces of the inner and outer ring bearings of the servo;

Step S102, rotate the inner and outer rings of the servo, and collect a plurality of spatial positions of the mark points rotating around the bearing through a binocular vision system;

Step S103, inputting a computer to fit the axis of rotation according to the plurality of spatial positions;

Step S104 , based on the rotation axis, measure the normal vectors of a certain plane fixed on the shaft at multiple times during the rotation process, so as to fit the centerline vector of the rotation of the cone surface.

In one embodiment, the target disk is magnetically adsorbed on the end faces of the inner and outer ring bearings of the servo at 5-15°.

In one embodiment, the binocular vision system acquires a plurality of spatial positions of the marked points rotating around the bearing, including: using the binocular vision system to acquire an image of the target disk during one rotation of the shaft at a constant speed.

In one embodiment, inputting the computer to fit the rotation axis includes: fitting the normal vector of the target disk at each moment in the computer.

In one embodiment, measuring the normal vectors of a certain plane fixed on the shaft at multiple times during the rotation process to fit the centerline vector of the conical surface rotation, including: by fitting the target disk normal vectors at multiple times The direction vector of the axis to be measured is obtained from the center line of rotation of the conical surface.

In one embodiment, fitting the normal vector of the target disk at each moment in the computer includes: using image processing technology to perform edge extraction in the computer, and then identifying all the marked points in the image through a feature recognition algorithm.

In one embodiment, the feature recognition algorithm is an ellipse recognition algorithm.

Another object of the present invention is to provide a rotary cone angle amplification servo axis measurement system, comprising:

The target plate is used for certain magnetic adsorption on the end faces of the inner and outer ring bearings of the servo;

The binocular vision system is used to collect multiple spatial positions of the marked points rotating around the bearing when the inner and outer rings of the servo are rotated;

The processing module is used for inputting the computer to fit the rotation axis according to the plurality of spatial positions, and measuring the normal vector of a certain plane fixed on the shaft at multiple moments during the rotation process based on the rotation axis, so as to fit the cone surface The centerline vector of gyration.

In one embodiment, on the surface of the circular galvanized iron sheet, a plurality of marking points are randomly and evenly distributed on the surface.

In one embodiment, the target disk is a circular galvanized iron sheet with a diameter of 80 mm, and the surface of the target disk is randomly and evenly distributed with 5 mm marking points, and the distribution range is more than 60 mm. The invention realizes the technical effect of the non-contact virtual axis measurement based on the binocular vision system. The binocular vision system collects images at multiple moments of the marked point rotating around the bearing, and then inputs the images into the computer to fit the axis of rotation.

As a specific embodiment, a rotary cone angle amplification servo axis measurement system of the present invention includes: a target plate, the target plate is an auxiliary measurement tool, which is a circular galvanized iron sheet with a diameter of 80mm, and the surface is randomly and uniformly dispersed 5mm mark points are arranged, and the distribution range is more than 60mm.

As a specific embodiment, in the present invention, the target disk is magnetically adsorbed on the end faces of the inner and outer ring bearings of the servo at 5-15°.

As a specific embodiment, the present invention rotates the inner and outer rings of the servo, and uses a binocular vision system to collect the images of the target disk during the uniform rotation of the shaft for one cycle for subsequent data fitting, and collects the images of the target disk at 300 moments during the rotation process, Assuming that the time for the shaft to rotate evenly for one cycle is t, the frame rate of binocular vision system acquisition is set to 300/t. For example, if the rotation time of a servo mechanism axis is 10 seconds, the frame rate of binocular vision system acquisition is set to 30 frames/second.

As a specific embodiment, the present invention counts each acquisition moment in the rotation process as a state, and each state has a pair of images collected by the two cameras of the binocular vision system. Extraction, and then through feature recognition algorithms such as ellipse recognition, all the marked points in the image can be identified, and then fit the space coordinates of the target disk plane in each state, and then calculate the normal vector of the target disk plane in each state.

As a specific embodiment, the present invention is based on the principle of conical surface fitting, that is, any plane fixed on the axis will rotate around the axis during the rotation of the axis, and the mathematical expression is that the unit normal vector of the surface at any time is in the direction of the axis. The direction vector is centered on the cone. The direction vector of the axis to be measured can be obtained by fitting the center line of rotation of the cone composed of the normal vectors of the target disk at 300 moments.

As a specific example, in the present invention, since any plane fixed on the shaft will rotate around the shaft during the rotation of the shaft, the mathematical expression is that the unit normal vector of the face at any time is on the conical surface centered on the axis direction vector superior. Using this principle, the normal vector of a certain plane fixed on the shaft can be measured at multiple times during the rotation process, and then the centerline vector of the rotation of the cone surface can be fitted, which is the measured direction vector of the axis to be measured. Based on this principle, the present invention designs a target disk for auxiliary measurement, and magnetically adsorbs the target disk on the bearing end face at a 5-15° angle to obtain a better measurement effect.

As a specific embodiment, in the present invention, the auxiliary measurement tooling target disk is adsorbed on the end faces of the inner and outer ring bearings of the servo. Rotate the inner and outer rings of the servo, and use the binocular vision system to collect the image of the target disk during one cycle of the shaft at a constant speed for subsequent data fitting, and finally fit the rotation centerline of the cone composed of the normal vectors of the target disk at multiple times. Get the direction vector of the axis to be measured.

As a specific embodiment, the target disk of the present invention is magnetically adsorbed on the end faces of the inner and outer ring bearings of the servo at 10°.

As a specific example, in the present invention, a total of 300 target disk images need to be collected during one rotation of the shaft, and the time for one rotation of the shaft is set to be t, and the frame rate of binocular vision system acquisition is set to 300/t.

As a specific embodiment, the present invention inputs images collected by binocular vision into a computer for processing.

As a specific embodiment, the present invention uses image processing technology to extract edges in a computer, and then uses feature recognition algorithms such as ellipse recognition to identify all marked points in the image, and then fits the plane space coordinates of the target disk in each state. , and then calculate the normal vector of the target disk plane in each state.

The present invention also provides a rotary cone angle amplification servo axis measurement system, comprising:

The target plate is used for certain magnetic adsorption on the end faces of the inner and outer ring bearings of the servo;

The binocular vision system is used to collect multiple spatial positions of the marked points rotating around the bearing when the inner and outer rings of the servo are rotated;

The processing module is used for inputting the computer to fit the rotation axis according to the plurality of spatial positions, and measuring the normal vector of a certain plane fixed on the shaft at multiple moments during the rotation process based on the rotation axis, so as to fit the cone surface The centerline vector of gyration.

As a specific embodiment, the system of the present invention adopts a binocular camera, a computer, and a target disk. The target disk is a circular galvanized thin iron sheet with a diameter of 80mm, with 5mm black and white two-color marking points randomly and evenly arranged on the surface, with a distribution range of more than 60mm, and the target disk is magnetically adsorbed on the end face of the shaft to be measured at 5°-15°. A binocular camera is used to collect the mark point data of the target disk, input it into the computer for processing, and finally fit the spatial angle of the virtual axis.

The surface of the circular galvanized thin iron sheet is randomly and evenly distributed with a plurality of marking points.

As a specific example, the target disk is a circular galvanized iron sheet with a diameter of 80 mm, and the surface of the target disk is randomly and evenly distributed with 5 mm marking points, and the distribution range is more than 60 mm.

As a specific example to rotate the inner and outer rings of the servo, the binocular vision system is used to collect the images of the target disk during the rotation of the shaft at a constant speed for subsequent data fitting, and the images of the target disk at 300 moments during the rotation process are collected. The time for one rotation is t, and the frame rate of binocular vision system acquisition is set to 300/t. For example, if the rotation time of a servo mechanism axis is 10 seconds, the frame rate of binocular vision system acquisition is set to 30 frames/second.

As a specific embodiment, the specific measurement process of a rotary cone angle amplification servo axis measurement system of the present invention is:

The first step: magnetically attach the target disk to the end faces of the inner and outer ring bearings of the servo at a 5-15° angle.

Step 2: Rotate the inner and outer rings of the servo, and use the binocular vision system to collect the images of the target disk during the rotation of the shaft at a constant speed for subsequent data fitting. Generally, it is necessary to collect the images of the target disk at 300 moments during the rotation process. The time for a uniform rotation is t, and the frame rate of binocular vision system acquisition is set to 300/t. For example, if the rotation time of a servo mechanism axis is 10 seconds, the frame rate of binocular vision system acquisition is set to 30 frames/second.

Step 3: Count each acquisition moment in the rotation process as a state, then each state has a pair of images collected by the two cameras of the binocular vision system, and the edge is extracted by using image processing technology in the computer, and then through the binocular vision system. Feature recognition algorithms such as ellipse recognition can identify all the marked points in the image, then fit the space coordinates of the target disk plane in each state, and then calculate the normal vector of the target disk plane in each state.

Step 4: According to the principle of conical surface fitting, that is, any plane fixed on the axis will rotate around the axis during the rotation of the axis. The mathematical expression is that the unit normal vector of the surface at any time is centered on the axis direction vector. on the cone surface. The direction vector of the axis to be measured can be obtained by fitting the center line of rotation of the cone composed of the normal vectors of the target disk at 300 moments.

The present invention achieves the following significant beneficial effects

The implementation is simple, including: magnetically attaching the target disk to the end faces of the inner and outer rings of the servo; rotating the inner and outer rings of the servo, and collecting multiple spatial positions of the marked points rotating around the bearing through a binocular vision system; The multiple spatial positions are input into the computer to fit the rotation axis; based on the rotation axis, the normal vectors of a certain plane fixed on the shaft at multiple times during the rotation process are measured to fit the cone surface rotation centerline vector. It can achieve the effect of non-contact measurement technology of virtual rotary axis based on binocular vision, and solve the problem that servo virtual rotary axis cannot be directly measured.

According to the technical solution and concept of the present invention, any other suitable modifications can also be made. For those of ordinary skill in the art, all these replacements, adjustments and improvements should fall within the protection scope of the appended claims of the present invention.

Claims (7)

1. A method of rotating cone angle amplified servo axis measurement, comprising:

firstly, magnetically adsorbing a target disc at 5-15 degrees to the end faces of inner and outer ring bearings of a servo;

secondly, rotating the inner and outer servo rings, and acquiring a plurality of spatial positions of the mark points rotating around the bearing through a binocular vision system;

then, inputting the plurality of spatial positions into a computer to fit a revolution axis;

and finally, measuring normal vectors of a certain plane fixed on the shaft at a plurality of moments in the rotating process based on the revolution axis so as to fit the revolution center line vector of the conical surface.

2. The method of gyratory cone angle amplification servo axis measurement according to claim 1, wherein the binocular vision system acquires a plurality of spatial positions of the marker points rotating about the bearing, including: and acquiring an image of the target disc during the uniform rotation of the shaft for one circle by using a binocular vision system.

3. The method of claim 1, wherein inputting a computer to fit the slew axis comprises: and fitting the normal vector of each moment of the target disk in the computer.

4. The method of claim 3, wherein measuring normal vectors of a plane fixed to the shaft at a plurality of times during rotation to fit the cone centerline of revolution vector comprises: and obtaining the direction vector of the shaft to be measured by fitting the rotation center line of the conical surface formed by the normal vectors of the target plate at a plurality of moments.

5. The method of claim 4, wherein fitting the normal vector to the target disk at each time in the computer comprises: and (3) extracting edges in a computer by using an image processing technology, and identifying all the mark points in the image by using a feature identification algorithm.

6. The method of claim 5, wherein the feature recognition algorithm is an ellipse recognition algorithm.

7. A rotary cone angle amplified servo axis measurement system, comprising:

the target disc is used for being magnetically adsorbed on the end faces of the servo inner ring bearing and the servo outer ring bearing at an angle of 5-15 degrees;

the binocular vision system is used for collecting a plurality of spatial positions of the mark points rotating around the bearing when the servo inner ring and the servo outer ring are rotated;

and the processing module is used for inputting the fitting rotation axis of the computer according to the plurality of spatial positions, measuring normal vectors of a certain plane fixed on the shaft at a plurality of moments in the rotating process based on the rotation axis, and fitting the rotation center line vector of the conical surface.

Images