CN105668286B - Three-stage synchronous alignment control method - Google Patents

Abstract

The invention discloses a three-stage synchronous alignment control method. The hardware includes two sets of transmission processing rollers, two alignment zero points, two rotary encoders, three alignment sensors and several processing mechanisms. The present invention divides the control process into three stages, which are the zero-point correction stage, the same-speed adjustment stage, and the alignment adjustment stage according to the sequence of the flow. The functions of the zero-point correction stage and the same-speed adjustment stage are to prepare for the synchronous alignment. Eliminate most of the adjustment amount. The alignment adjustment stage is responsible for precise adjustment to achieve the objective result of synchronous alignment. Through three-stage adjustments, the long flexible workpiece can be synchronized on the two transmission processing roller stations. Counterpoint processing overcomes the problem of product process size error caused by elastic deformation of long flexible workpieces or mechanical mechanism processing and assembly accuracy, and realizes automatic production while ensuring high processing accuracy of products.

Description

A three-stage synchronous alignment control method

technical field

The invention belongs to the field of synchronous alignment control, and in particular relates to a control method which divides the control process into three stages and enables two processing rollers for conveying and processing long flexible workpieces to perform synchronous alignment operation.

Background technique

With the development of society and the advancement of science and technology, the use of automated production lines is becoming more and more common, and the production process of its products is becoming more and more complex. In the production process, it is often seen that two or more different processes are performed on the same part of the workpiece, and different processes are carried out by different equipment. In order to ensure processing quality, improve production efficiency, and strictly realize unmanned, these equipments on the production line must have the ability of synchronous alignment, and several different equipments must ensure highly accurate spatial positions, highly coordinated time, and Highly synchronized movement.

For a production line that processes rigid workpieces, it is relatively easy to achieve synchronous alignment, because the size and shape of the processed workpieces are not easy to change, and it is relatively easy to realize the positioning of a certain point on the processed workpiece. However, for production lines that process flexible workpieces, it is very difficult to achieve synchronous alignment, especially for production lines that use rollers to convey and process long flexible workpieces. The elastic deformation of long flexible workpieces is very large and difficult to control. A slightly larger restraining force on the long flexible workpiece will lead to elongation, deformation or even breaking of the long flexible workpiece, and a slightly smaller restraint tension on the long flexible workpiece will cause the long flexible workpiece to be processed The parts are bent and piled up, making it difficult to apply force "just right".

The above situation makes it difficult to automate the production line for processing long flexible workpieces. Many processes that require synchronous alignment can only be completed by manual control, and the production efficiency and quality cannot be improved. Now there is a need for a control method that can be applied to the production line that uses rollers to convey and process long flexible workpieces, so that the production line can have the ability of synchronous alignment, and the equipment in the production line can be accurate, coordinated, and synchronized. To truly unmanned and automated.

Contents of the invention

In view of this, aiming at the deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a three-stage synchronous alignment control method, which divides the control process into three stages, which are the zero-point correction stage, the same-speed In the adjustment stage and the alignment adjustment stage, the two rollers for conveying and processing long flexible workpieces can achieve synchronous alignment and realize the automation of the production line.

In order to achieve the above object, the present invention has the following structural composition: on the conveying track line (3) of the processed workpiece, a transmission processing roller 1 (1) and a transmission processing roller 2 (2) are successively arranged along the positive direction of the X axis. The transmission processing roller 1 (1) is equipped with a counterpoint zero point 1 (11), a rotary encoder 1 (13), and several processing mechanisms 1 (14) uniformly arranged in a ring shape, and the transmission processing roller 1 (1) A registration sensor 1 (12) is arranged near the drive processing roller 2 (2), which is equipped with a registration zero point 2 (21), a rotary encoder 2 (23), and several processing rollers evenly arranged in a ring shape. Mechanism 2 (24), the alignment sensor 2 (22) is arranged near the transmission processing roller 2 (2), located between the transmission processing roller 1 (1) and the transmission processing roller 2 (2) A registration sensor 3 (4) is arranged on it, and the corresponding position of the registration sensor 3 (4) on the conveying track line (3) of the workpiece is the synchronous registration point 1 (61), and the transmission processing roller The position corresponding to 2(2) on the conveying track line (3) of the workpiece is the synchronous alignment point 2(62).

Based on the above-mentioned structure, the control flow of the present invention is as follows: the control is divided into three stages, which are the zero point correction stage, the same speed adjustment stage, and the alignment adjustment stage according to the sequence of the flow. In the zero-point correction stage, the drive processing roller 1 (1) rotates to align the alignment zero point 1 (11) with the alignment sensor 1 (12), and at the same time drives the processing roller 2 (2) to rotate to align the alignment zero point 2 (21 ) and alignment sensor 2 (22), the zero point calibration is completed. In the same-speed adjustment stage, the transmission processing roller 1 (1) and the transmission processing roller 2 (2) start to accelerate from static to rotate counterclockwise at the same time, when the transmission processing roller 1 (1) and the transmission processing roller When the rotational speed of 2(2) reaches the preset speed at the same time and remains stable, the adjustment at the same speed is completed, and the rotational speed of the transmission processing roller 1(1) is detected by the rotary encoder 1(13), and the transmission processing roller 2 The rotational linear velocity of (2) is detected by the rotary encoder 2 (23). In the alignment adjustment stage, the control system calculates the dynamic coordinates of all processing mechanisms 2 (24) in real time through the rotary encoder 2 (23), and every time the alignment zero point 2 (21) and the alignment sensor 2 (22) are aligned, The dynamic coordinates of all the processing mechanisms 2 (24) are calibrated once according to the structural dimensions. Assuming that the distance between the synchronous alignment point 1 (61) and the synchronous alignment point 2 (62) is L, when the alignment sensor 3 (4) is triggered, the control system calculates that the processing roller 1 is driven at this moment. The linear speed of rotation of (1) walks through the time required for the stroke of length L, assuming that the time is t, and calculates according to the linear speed of rotation of the transmission processing roller 2 (2) at this moment after the elapsed time t The estimated coordinates of all processing mechanisms 2 (24), judge the processing mechanism 2 (24) closest to the synchronous alignment point 2 (62) from the estimated coordinates, and then the control system changes and controls the transmission processing roller 2 (2) Rotate the linear speed so that the processing mechanism 2 (24) is just at the corresponding position of the synchronous alignment point 2 (62) after the elapse of time t. The alignment adjustment stage can run in a continuous cycle to realize continuous synchronous alignment.

The advantages of the present invention are as follows: the transmission processing roller 1 (1) and the transmission processing roller 2 (2) can run synchronously, and the transmission processing roller 2 (2) has independent adjustment and correction capabilities, and the three-stage adjustment makes the The long flexible workpiece is processed synchronously on the two transmission processing roller stations, which overcomes the problem of product process dimension error caused by the elastic deformation of the long flexible workpiece or the processing and assembly accuracy of the mechanical mechanism, and realizes Automated production also ensures that the product has high processing accuracy. The function of the zero-point correction stage and the same-speed adjustment stage is to prepare for the synchronous alignment, and the role of the alignment adjustment stage is to achieve the result of synchronous alignment objectively. This three-stage division method makes the control process more efficient. Reasonably, the first two stages deal with most of the adjustments of the spatial position and velocity, and the third stage only needs to precisely adjust the spatial position and velocity within a small range, making the process of precise adjustment more efficient. It is stable and more controllable, greatly improving the accuracy of adjustment results, similar to the relationship between "rough machining" and "finish machining".

Description of drawings

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

FIG. 1 is a schematic diagram of zero point correction of a three-stage synchronous alignment control method.

FIG. 2 is a schematic diagram of the same-speed adjustment of a three-stage synchronous alignment control method.

FIG. 3 is a schematic diagram of alignment adjustment in a three-stage synchronous alignment control method.

FIG. 4 is a schematic diagram of successful processing of a three-stage synchronous alignment control method.

In the figure, 1—transmission processing roller 1, 11—alignment zero point 1, 12—alignment sensor 1, 13—rotary encoder 1, 14—processing mechanism 1, 2—transmission processing roller 2, 21—alignment Zero point 2, 22—alignment sensor 2, 23—rotary encoder 2, 24—processing mechanism 2, 3—transport trajectory of workpiece to be processed, 4—alignment sensor 3, 5—workpiece to be processed, 51—alignment processing point, 52—the alignment processing point after processing, 61—the synchronous alignment point 1, and 62—the synchronous alignment point 2.

detailed description

A typical specific implementation is as follows: assuming that the production process is as follows, the workpiece (5) is a long flexible piece, and the workpiece (5) moves in the positive direction of the X axis along the conveying track line (3) of the workpiece, and the power of the movement is given by The transmission processing roller 1 (1) and the transmission processing roller 2 (2) are provided by rotation, and during the rotation of the transmission processing roller 1 (1), the processing mechanism 1 (14) will be on the workpiece (5 ) to carry out the processing operation to generate the counterpoint processing point (51), when the counterpoint processing point (51) reaches the area where the transmission processing roller 2 (2) is located, during the rotation process of the transmission processing roller 2 (2), the processing Mechanism 2 (24) needs to process the alignment processing point (51), and the alignment processing point (51) becomes the alignment processing point (52) after processing. Before feeding the production line, the control system first enters the zero point calibration stage, as shown in Figure 1, the transmission processing roller 1 (1) rotates to align the alignment zero point 1 (11) with the alignment sensor 1 (12), and the transmission processing Roller 1 (1) stops and stops, and at the same time drives the processing roller 2 (2) to rotate to align the alignment zero point 2 (21) with the alignment sensor 2 (22), and drives the processing roller 2 (2) to stop and stand still , the zero-point calibration is over. At this time, all processing mechanisms 1 (14) and all processing mechanisms 2 (24) have clear position correspondences. The control system records the coordinates of all processing mechanisms 2 (24) at this time and sets as the initial value. After the zero point correction, the control system enters the same-speed adjustment stage, as shown in Figure 2, the transmission processing roller 1 (1) and the transmission processing roller 2 (2) start to rotate counterclockwise with the same acceleration from rest at the same moment , when the rotational linear speeds of the transmission processing roller 1 (1) and the transmission processing roller 2 (2) both reach the preset speed and remain stable, the same-speed adjustment ends. Assuming that the preset speed is v, due to the manufacturing and installation error of mechanical equipment, the performance difference of the motor and its transmission mechanism, the inertia of the actuator itself, and the influence of the environment, the transmission processing roller 1 (1) and the transmission processing roller 2 (2) It is difficult to accurately control the actual rotating line speed at the value of the preset speed v, but it is within a small range, and at this time it is regarded as reaching the preset speed v. In order to achieve precise control, it is assumed that the rotational speed of transmission processing roller 1 (1) is v ₁ , the rotational speed of transmission processing roller 2 (2) is v ₂ , and the rotation speed of transmission processing roller 1 (1) is The linear velocity is detected by the rotary encoder 1 (13), and the rotational linear velocity of the transmission processing roller 2 (2) is detected by the rotary encoder 2 (23). After the same-speed adjustment, the control system enters the alignment adjustment stage. As shown in Figure 3, the production line starts to load materials, and the workpiece (5) is driven by the transmission processing roller 1 (1) and the transmission processing roller 2 (2). The bottom moves to the positive direction of the X-axis along the conveying track line (3) of the workpiece. In the alignment adjustment stage, the rotational speed of the transmission processing roller 2( ₂ ) can be changed within a small range of v2 under the control of the control system. The control system measures and calculates all processing The dynamic coordinates of the mechanism 2 (24), and every time the alignment zero point 2 (21) and the alignment sensor 2 (22) are aligned, the dynamic coordinates of all the processing mechanisms 2 (24) are based on the transmission of the processing roller 2 (2) The inherent structural size is calibrated once, and the calibration method is that when the alignment zero point 2 (21) and the alignment sensor 2 (22) are aligned, the dynamic coordinates of all processing mechanisms 2 (24) return to the initial value, thus ensuring that the processing mechanism 2 ( 24) The cumulative error of the dynamic coordinates is cleared every time the transmission processing roller 2 (2) rotates once, so that the dynamic coordinates of the processing mechanism 2 (24) always maintain an accurate value. The corresponding position of the alignment sensor 3 (4) on the conveying track line (3) of the workpiece is the synchronous alignment point 1 (61), and the transmission processing roller 2 (2) is on the conveying trajectory line (3) of the workpiece The corresponding position is the synchronous alignment point 2 (62), and the distance between the synchronous alignment point 1 (61) and the synchronous alignment point 2 (62) is L, and L is the structural size produced after the production line is installed. After measurement, it is a fixed constant value. The selection principle of L is: according to the control algorithm described later, ensure that the control system has sufficient response time, and on this basis, it should be as short as possible. During the rotation of the drive processing roller 1 (1), the processing mechanism 1 (14) performs processing operations on the workpiece (5) to generate an alignment processing point (51), and the alignment processing point (51) is represented by v ₁ The speed moves to the positive direction of the X axis along the conveying trajectory line (3) of the workpiece. When the alignment processing point (51) reaches the synchronous alignment point ₁ (61), the alignment sensor 3 (4) is triggered. At this time, the control system cooperates with the speed time displacement formula to calculate the The time required to complete the stroke of length L is assumed to be t, the formula is L/v ₁ =t, and according to the rotational linear velocity v ₂ of the processing roller 2 (2) at this moment, the matching speed The time displacement formula calculates the arc length L ₁ passed by the processing mechanism 2 (24) after the elapsed time t, the formula is v ₂ t=L ₁ , and calculates all the processing mechanisms 2 (24) at the elapsed time according to L ₁ The estimated coordinates after t, and the arc length ΔL _i from the estimated coordinates of each processing mechanism 2 (24) to the synchronous alignment point 2 (62), (i=1, 2, 3...), and then judge Find the processing mechanism 2 (24) whose estimated coordinates are closest to the synchronous alignment point 2 (62), that is, min|ΔL _i |, (i=1, 2, 3...). Assume that the arc length from the actual coordinates of the processing mechanism 2 (24) to the synchronous alignment point 2 (62) when the alignment sensor 3 (4) is triggered is L ₂ , if the processing mechanism 2 (24) passes through After the time t, the synchronous alignment point 2 (62) is just reached, that is, the processing mechanism 2 (24) travels with an arc length of L ₂ at the time t, and the goal of synchronous alignment is achieved. Now given a simultaneous formula:

Among them, a is the linear acceleration of the transmission processing roller 2 (2) when performing the alignment adjustment action, and the linear acceleration a is obtained after the installation of the production line through experimental measurement, analysis and calculation to ensure that the transmission processing roller 2 (2) The optimal value for the smooth, accurate and efficient alignment adjustment action is a fixed constant value; △t is the time when the transmission processing roller 2(2) is affected by the linear acceleration a, and the control system is based on the above-mentioned simultaneous Calculated by the formula; v _t is the rotational linear velocity of the transmission processing roller 2 (2) after the linear acceleration a, which is calculated by the control system according to the above simultaneous formula; the positive and negative sign determination method in the simultaneous formula : When L ₂ -L ₁ >0, the sign is positive; when L ₂ -L ₁ <0, the sign is negative. The practical significance of the simultaneous formula is that from the moment when the registration sensor 3(4) is triggered, the transmission processing roller 2( ₂ ) takes v2 as the initial rotational speed and a as the linear acceleration to reach the rotational speed after time △t v _t , and then rotate at a constant speed of v _t (t-△t) for a period of time, and the arc length travel of the final drive processing roller 2(2) at time t is L ₂ . As shown in Figure 4, the effect obtained is that when the alignment processing point (51) arrives at the synchronous alignment point 2 (62), a processing mechanism 2 (24) arrives at the synchronous alignment point 2 (62), and then the The processing mechanism 2 (24) processes the alignment processing point (51), and the alignment processing point (51) becomes the processed alignment processing point (52). After entering the alignment adjustment stage, the control system will execute the alignment adjustment stage cyclically to realize continuous synchronous alignment until the production line stops production.

The working principle of the present invention is analyzed in detail as follows: in the control process of the present invention, the driving processing roller 2 (2) is made synchronously aligned with respect to the driving processing roller 1 (1) and the workpiece (5). The result is to realize the alignment of spatial position at a certain point in time, and the manipulated variables are spatial position and speed. Because there are unpredictable and unnegligible random dimensional errors in the long flexible workpiece, coupled with the influence of equipment performance, the simple control of the transmission processing roller 1 (1) and the transmission processing roller 2 (2) at the same speed The method of rotation is difficult to achieve accurate synchronous alignment, so the transmission processing roller 2 (2) must have independent adjustment and correction capabilities to overcome the dimensional error problem caused by the elastic deformation of the long flexible workpiece. The zero-point correction stage enables the transmission processing roller 1 (1) and the transmission processing roller 2 (2) to have a clear spatial position correspondence, eliminating most of the adjustment amount of the spatial position. The same-speed adjustment stage makes the transmission processing roller 1 (1) and the transmission processing roller 2 (2) have a clear line speed corresponding relationship, eliminating most of the adjustment amount of the line speed. The alignment adjustment stage is responsible for precise adjustment and realization of the objective result of synchronous alignment, the spatial position and speed of the alignment processing point (51) is the synchronous alignment target, and the spatial position and speed of the transmission processing roller 2 (2) is the adjustment object , use alignment sensor 3 (4), rotary encoder 1 (13), rotary encoder 2 (23), production line structure size, alignment sensor 2 (22), alignment zero point 2 (21) to determine the synchronous alignment target and the adjustment amount between the adjustment object, and then control the adjustment object to realize the synchronous alignment with the synchronous alignment target according to the adjustment amount. In the alignment adjustment stage, the adjusted rotational linear velocity of the transmission processing roller 2 (2) is v _t , although it is different from the velocity v ₁ of the alignment processing point (51), but because the linear velocity is eliminated in the same-speed adjustment stage Most of the adjustment amount, so in fact, the difference between v _t and v ₁ is very small, which can be fully tolerated by the flexible characteristics of the long flexible workpiece, and will not cause the tearing of the long flexible workpiece .

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Apparently, those skilled in the art can make various changes and deformations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and equivalent technologies, the present invention also includes these modifications and variations.

Claims (4)

1. a kind of three stage synchronization aligning control method, it is characterised in that：The structure composition that control method is relied on is as follows, in quilt Transmission processing roller 1 (1) and transmission processing roller 2 (2) are successively disposed with along X-axis positive direction on workpiece conveying trajectory (3), The number for being provided with para-position 0. 1 (11), rotary encoder 1 (13), being evenly arranged with ring-type on the transmission processing roller 1 (1) Individual organisation of working 1 (14), being disposed about to level sensor 1 (12) for the transmission processing roller 1 (1) is described to be driven processing The several organisation of workings 2 for para-position 0. 2 (21), rotary encoder 2 (23) are provided with roller 2 (2), being evenly arranged with ring-type (24), the transmission processing roller 2 (2) has been disposed about to level sensor 2 (22), in the transmission processing roller 1 (1) and Transmission processing roller 2 (2) between position on be disposed with to level sensor 3 (4), it is described to level sensor 3 (4) in work piece Corresponding position is synchronous loci 1 (61) in conveying trajectory (3), and the transmission processing roller 2 (2) is conveyed in work piece Corresponding position is synchronous loci 2 (62) in trajectory (3)；The structure composition is relied on, control flow is divided into three phases, It it is zero correction stage, synchronized metamorphosis stage, para-position metamorphosis stage by flow process sequencing.

2. a kind of three stage synchronization aligning control method according to claim 1, it is characterised in that：In the zero correction In the stage, the transmission processing roller 1 (1) is rotated to be made para-position 0. 1 (11) and level sensor 1 (12) is aligned, while the biography Dynamic processing roller 2 (2) is rotated to be made para-position 0. 2 (21) and level sensor 2 (22) is aligned.

3. a kind of three stage synchronization aligning control method according to claim 1, it is characterised in that：In the synchronized adjustment Stage, the transmission processing roller 1 (1) and transmission processing roller 2 (2) are started to accelerate to side counterclockwise in synchronization from static To rotation, make the transmission processing roller 1 (1) and transmission process roller 2 (2) linear velocity and meanwhile reach pre-set velocity and Keep stable, the linear velocity of the transmission processing roller 1 (1) is detected by rotary encoder 1 (13), the transmission processing roller The linear velocity of cylinder 2 (2) is detected by rotary encoder 2 (23).

4. a kind of three stage synchronization aligning control method according to claim 1, it is characterised in that：In para-position adjustment Stage, control system calculates in real time the dynamic coordinate of all organisation of workings 2 (24) by the rotary encoder 2 (23), and Para-position 0. 2 (21) and level sensor 2 (22) is often aligned once, the dynamic coordinate of all organisation of workings 2 (24) is with regard to root Calibrate once according to physical dimension；If the distance between synchronous loci 1 (61) and synchronous loci 2 (62) are L, when para-position is sensed When device 3 (4) is triggered, control system is calculated to be covered length at moment and is with the linear velocity of this transmission processing roller 1 (1) Time required for the stroke of L, if the time is t, and according to the rotational line of this moment transmission processing roller 2 (2) What velometer calculated after elapsed time t all organisation of workings 2 (24) estimates coordinate, judges that described to estimate coordinate distance same The nearest organisation of working 2 (24) of loci 2 (62) is walked, then control system changes and control the transmission processing roller 2 (2) Linear velocity, makes the organisation of working 2 (24) after elapsed time t just at the corresponding position of synchronous loci 2 (62) Put；The para-position metamorphosis stage can continuously circular flow, realize continuous synchronization para-position.