JP2022178404A - Control system, control method and program - Google Patents

Abstract

To provide a technique for realizing, in a device including a plurality of movable members, control for moving the plurality of movable members synchronously so that a speed at the end of a moving track of each movable member becomes a target speed.SOLUTION: A control system for a device including a plurality of movable members capable of moving, includes: moving-track calculating means that calculates a moving track for each of the plurality of movable members; moving-time calculating means that calculates a moving time by which a target end speed can be realized, for each of the plurality of movable members; common-moving-time determining means that determines one common moving time by which each of the plurality of movable members can realize the target end speed, based on the moving times respectively calculated for each of the plurality of movable members; and control command means that causes the device to perform a control including a speed control for moving each of the plurality of movable members from a point on each of the specific moving tracks to the end point in the common moving time.SELECTED DRAWING: Figure 1

Description

The present invention relates to the control of devices comprising a plurality of movable members capable of movement in at least two dimensions.

2. Description of the Related Art Conventionally, devices that work by coordinating a plurality of movable members (hereinafter also referred to as axis groups) have been widely used. There are various types and uses of such devices. There is an X-ray inspection device that creates dimensional data and inspects the internal structure of the inspection location.

In such an X-ray inspection apparatus, X-rays are emitted from an X-ray source to an inspected portion of an object to be inspected, and the transmitted X-rays are photographed by an X-ray camera. A plurality of X-ray images are captured while relatively changing the positional relationship among the X-ray source, the object to be inspected, and the X-ray camera. At this time, at least one of the X-ray source, the object to be inspected, and the X-ray camera is rotated to change their relative positions. It is moved to a photographing position for photographing the examination location, and is further rotated. Conventionally, the movable member such as the X-ray source is temporarily stopped at the timing of the transition between the moving motion and the rotating motion, that is, before and after the rotating motion, and then the next moving motion/rotating motion is started again. was

By the way, such a stop operation itself becomes a factor that prolongs the total inspection time. Since it is likely to vibrate and the imaging quality deteriorates, there is an empty transport period during which an inspection image cannot be captured until the vibration subsides, which further prolongs the inspection time.

Therefore, it is conceivable to reduce the inspection time by eliminating the stop time before and after the turning motion and connecting the turning motion and the moving motion with a continuous speed (acceleration, jerk). However, since the X-ray source and the X-ray camera must be placed facing each other with respect to the object to be inspected, in order to eliminate the stop time and to match the start timing of the turning movement of the X-ray source and the X-ray camera, , the travel time of both must be the same.

In order to specify the movement time between two points and to smoothly connect them so that the acceleration does not become discontinuous, the movable member is moved by a trajectory using a quintic interpolation trajectory as disclosed in Non-Patent Document 1, for example. can be considered. However, the moving distances of the X-ray source and the X-ray camera do not necessarily match, and if one of the moving distances is short, the moving trajectory generated to adjust the moving time expands more than necessary, There is a risk of exceeding the movable range of.

In this regard, Patent Literature 1 describes a technique for preventing the generation of a movement trajectory that deviates from the control vector by specifying the movement trajectory between two points with a Bezier curve defined by the control vector. there is Further, it is also described that the moving speed for realizing the target speed and the target acceleration of the moving object at the end point of the movement is calculated in real time for each control cycle and the control is performed. According to the technique described in Patent Literature 1, the trajectory between the starting point vector and the end point vector is specified only, and the velocity (acceleration) at the end point of the locomotion does not become discontinuous. It is possible to smoothly connect the start point and the end point.

JP-A-2012-83982

Tsuneo Yoshikawa, "Robot Control Fundamentals", Corona Publishing, 1988, p. 132-133

The technique described in Patent Document 1 relates to an apparatus with one axis group, but as described above, in the X-ray inspection apparatus, a plurality of axis groups (of the X-ray source and the X-ray camera) are operated synchronously. There is a need. That is, it is necessary to equalize the movement times of the movement sections of the respective axis groups, but since the movement times suitable for realizing the target speed at the end point of the movement section differ for each axis group, synchronous control becomes difficult. This problem could not be solved by the technique described in Patent Document 1.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to generate an appropriate movement trajectory for each movable member in an apparatus having a plurality of movable members, and to prevent movement of each movable member. It is an object of the present invention to provide a technique for realizing control for moving a plurality of movable members in synchronization such that the speed at the track end point becomes a target speed.

The present invention for solving the above problems employs the following configuration. Namely
A control system for a device comprising a plurality of movable members, comprising:
movement trajectory calculation means for calculating, for each of the plurality of movable members, a specific movement trajectory that is a path connecting a start point and an end point related to movement of the movable member and is specified using a polynomial;
The time required for each of the plurality of movable members to move from one point on the specific movement trajectory to the end point, and the movement that allows the movable member to achieve a target terminal velocity, which is a predetermined speed to be maintained at the end point. travel time calculation means for calculating time;
Common travel time identification for determining one common travel time at which each of the plurality of movable members can achieve the target terminal velocity at the end point based on the plurality of travel times calculated for each of the plurality of movable members. means and
and control command means for causing the device to execute control including speed control for moving each of the plurality of movable members from the one point on each of the specific movement trajectories to the end point in the common movement time. there is
A control system characterized by:

According to this, in an apparatus having a plurality of movable members, an appropriate movement trajectory is generated for each movable member, and the speed at the end point of the movement trajectory of each movable member becomes a target speed. can be controlled to move synchronously.

Further, the common travel time specifying means may determine the longest travel time among the plurality of travel times calculated for each of the plurality of movable members as the common travel time. According to this, it is possible to set a common movement time that allows all the movable members to move reasonably and most efficiently for the apparatus as a whole.

Further, the movement time calculation means calculates a remaining trajectory movement time required for each of the plurality of movable members to reach the end point from the current position at each predetermined control cycle during movement control of the movable member,
The common travel time determining means determines and updates one common remaining track travel time for each control cycle based on the remaining travel time for each movable member calculated for each control cycle. ,
The control command means controls the device to move each of the plurality of movable members from the current position to the end point with the latest common remaining track movement time updated every control cycle. It may be something that causes

With such a configuration, it is possible to perform synchronous control of a plurality of movable members in real time. Therefore, it is possible to control the movement of the movable member without calculating the movement time in advance. Also, even if it becomes impossible for the movable member to complete the movement within the calculated movement time for some reason, the movement time is corrected in real time and the synchronous control of the multiple movable members is continued. it becomes possible to

Further, the movement time calculation means calculates the remaining trajectory using the current velocity of the movable member, the target terminal velocity, and the remaining trajectory length from the current position of the movable member to the end point of the specific movement trajectory. Orbit travel time may be calculated. The remaining trajectory length may be measured using a sensor, for example, or may be obtained by calculation using an elementary function or the like.

In addition, the control system controls, in each control cycle, the target acceleration or The control command means is adapted to move each of the plurality of movable members so as to satisfy the target acceleration or the target jerk calculated for each control cycle. Control may be performed by the device.

Further, the acceleration calculation means
The target acceleration is accRefNonLimited, the target terminal velocity is refVelEnd, the current velocity is actVel, the common remaining trajectory movement time is tLeft, and the target terminal velocity can be realized with the common remaining trajectory movement time. The end point of the specific movement trajectory If Vnec is the speed required to reach
accRefNonLimited=(2*Vnec-refVelEnd-actVel)/tLeft
The target acceleration may be calculated by the following formula.

Further, the acceleration calculation means uses a predetermined acceleration correction coefficient α to
The target acceleration is accRefNonLimited, the target terminal velocity is refVelEnd, the current velocity is actVel, the common remaining trajectory movement time is tLeft, and the target terminal velocity can be realized with the common remaining trajectory movement time. The end point of the specific movement trajectory If Vnec is the speed required to reach
accRefNonLimited=(Vnec−actVel+α×(Vnec−refVelEnd))/tLeft
The target acceleration may be calculated by the following formula.

By updating the common travel time with the remaining track travel time calculated for each control cycle, the acceleration at the end point of the specific travel trajectory may increase. In this respect, as described above, the acceleration correction coefficient α is used to calculate an acceleration that is greater than the acceleration required to achieve the target terminal velocity, and the velocity of the movable member is increased in advance. Discontinuity of acceleration (rapid change in acceleration) at the end point of the trajectory can be prevented.

Further, the acceleration calculating means may output the limit value as the target acceleration or the target jerk when the calculated target acceleration or the target jerk exceeds a predetermined limit value. With such a configuration, the acceleration/jerk can be clipped so as not to exceed a predetermined limit value set based on the load on the device.

Further, the common remaining trajectory moving time may be determined as an integral multiple of the control period. If the calculated movement time is not an integral multiple of the control period, the acceleration at the track connection points (the start and end points of the specific movement track) becomes discontinuous, and abnormal noise is generated at the track connection points. Such a configuration is preferable.

The movement time calculation means calculates an entire trajectory movement time, which is a movement time from the start point to the end point of the specific movement trajectory, for each of the plurality of movable members before movement control of the movable members, and calculates the common movement. The time determination means may determine one common total track movement time based on the plurality of total track movement times calculated for each of the plurality of movable members. According to this, it is possible to smoothly control the movement after calculating the movement time of the movable member in advance.

Further, the movement time calculation means uses as input information at least a target initial velocity, which is a predetermined velocity to be maintained by the movable member at the starting point, and the target terminal velocity, and the movable member moves along the specific movement trajectory. may be calculated as the movement time during which the acceleration from the target initial velocity to the target terminal velocity is constant when moving from the start point to the end point. According to this, since the acceleration is constant and continuous from the start point to the end point of the movement trajectory, it becomes possible for the movable member to more smoothly transition from the end point of the movement trajectory to the next operation.

Further, the movement time calculation means inputs the target initial velocity, the target terminal velocity, and a limit acceleration, which is a limit value of the acceleration until the movable member reaches the target terminal velocity from the target initial velocity, as input information. The travel time may be calculated by searching for the travel time at an acceleration that does not exceed the limit acceleration.

Further, the limited acceleration is defined as a limited target acceleration refAcc for the movable member to reach the target terminal velocity from the target initial velocity, the target terminal velocity is refVelEnd, the target initial velocity is refVelStart, and the acceleration in the specific movement trajectory is refVelEnd. When the remaining trajectory length to the end point is resLen,
The limited target acceleration may be determined by the formula refAcc=(refVelEnd ² -refVelStart ² )/(2×resLen).

Also, the polynomial may represent a Bezier curve or a clothoid curve. According to this, it becomes possible to easily design a movement trajectory in which each movable member does not deviate from a predetermined movement range.

Further, the apparatus includes an X-ray source that generates X-rays that irradiate an object to be inspected, an X-ray camera that captures an X-ray image of the X-rays that are irradiated from the X-ray source to the object to be inspected, and the object to be inspected. An X-ray inspection apparatus comprising a holding unit that holds the
The plurality of movable members may include at least any two or more of the X-ray source, the X-ray camera, and the holding section. The present invention is suitable for such devices.

The present invention also provides a control method for an apparatus having a plurality of movable members, comprising:
a movement trajectory calculating step of calculating, for each of the plurality of movable members, a specific movement trajectory that is a path connecting a start point and an end point related to movement of the movable member and is specified using a polynomial;
The time required for each of the plurality of movable members to move from one point on the specific movement trajectory to the end point, and the movement that allows the movable member to achieve a target terminal velocity, which is a predetermined speed to be maintained at the end point. a travel time calculation step of calculating the time;
common travel time determination for determining one common travel time that enables each of the plurality of movable members to achieve the target terminal velocity at the end point based on the plurality of travel times calculated for each of the plurality of movable members; a step;
and a control command step for causing the device to execute control including speed control for moving each of the plurality of movable members from the one point on each of the specific movement trajectories to the end point in the common movement time. It can also be regarded as a control method characterized by

The present invention can also be regarded as a program for causing a computer to execute each of the above steps, or a computer-readable recording medium on which such a program is non-temporarily recorded.

It should be noted that each of the above configurations and processes can be combined with each other to form the present invention as long as there is no technical contradiction.

According to the present invention, in an apparatus having a plurality of movable members, an appropriate movement trajectory is generated for each movable member, and the speed at the end point of the movement trajectory of each movable member becomes a target speed. It is possible to provide a technique for realizing control for moving the movable members synchronously.

FIG. 1 is a diagram showing an outline of an X-ray inspection apparatus according to an embodiment of the present invention. FIG. 2A is a diagram showing the relationship between the turning motion and the moving motion of an X-ray source or an X-ray camera in a conventional example. FIG. 2B is a diagram showing the relationship between the turning motion and the moving motion of the X-ray source or X-ray camera in the embodiment of the present invention. FIG. 3 is a diagram showing an example of trajectories of turning motion and moving motion of an X-ray source or an X-ray camera in an embodiment of the present invention. FIG. 4 is a diagram for explaining the movement trajectory of the X-ray source or X-ray camera during movement in the embodiment of the present invention. 5A and 5B are diagrams for explaining processing related to movement time calculation during movement of the X-ray source or the X-ray camera in the embodiment of the present invention. 6A and 6B are diagrams for explaining processing related to movement time calculation during movement of the X-ray source or the X-ray camera in the embodiment of the present invention. FIG. 7A is a diagram showing an example of a movement trajectory during movement of the X-ray source or X-ray camera in the embodiment of the present invention. FIG. 7B is a graph showing an example of the relationship between speed and movement time during movement of the X-ray source or X-ray camera in the embodiment of the present invention. FIG. 8A is a diagram showing an example of a movement trajectory during movement of the X-ray source 10 in the embodiment of the present invention. FIG. 8B is a graph showing the relationship between the moving speed and moving time of the X-ray source 10 in the embodiment of the present invention. FIG. 8C is a diagram showing an example of a movement trajectory during movement of the X-ray camera 20 according to the embodiment of the present invention. FIG. 8C is a graph showing the relationship between the moving speed and moving time of the X-ray camera 20 in the embodiment of the present invention. FIG. 9A is a diagram showing an example of a movement trajectory during movement of the X-ray source 10 in the embodiment of the present invention. FIG. 9B is a graph showing the relationship between the moving speed and moving time of the X-ray source 10 in the embodiment of the present invention. 10A and 10B are diagrams for explaining processing related to remaining trajectory movement time calculation during movement of the X-ray source or X-ray camera in the embodiment of the present invention. 11A and 11B are diagrams for explaining processing related to remaining trajectory movement time calculation during movement of the X-ray source or X-ray camera in the embodiment of the present invention. FIG. 12A is a diagram illustrating processing related to remaining trajectory movement time calculation during movement of the X-ray source or X-ray camera in the embodiment of the present invention. FIG. 12B is a diagram illustrating processing related to remaining trajectory movement time calculation during movement of the X-ray source or X-ray camera in the embodiment of the present invention. FIG. 13 is a block diagram showing the flow of information processing for current position calculation during movement of the X-ray source or X-ray camera in the embodiment of the present invention. FIG. 14 is a flow chart showing the flow of processing related to synchronous movement of the X-ray source 10 and X-ray camera 20 in the embodiment of the present invention.

<Application example>
An outline of an application example of the present invention will be described below with reference to some of the drawings. The present invention can be applied to an X-ray inspection apparatus 1 as shown in FIG. In the X-ray inspection apparatus 1, an X-ray source 10 irradiates an object S to be inspected with X-rays, and an X-ray camera 20 captures an X-ray image based on the amount of transmission. The X-ray source 10 and the X-ray camera 20 orbit on orbital circles 121 and 122, respectively, and take X-ray images of the inspection object S at a plurality of positions on the orbit. After that, both the X-ray source 10 and the X-ray camera 20 move to the next turning circle in order to inspect another inspection point, and take an X-ray image while making a turning movement on the turning circle. . Note that the X-ray source 10 and the X-ray camera 20 may also be referred to as "movable member" or "axis group" below.

Here, when the X-ray source 10 and the X-ray camera 20 shift from turning motion to moving motion, conventionally, as shown in FIG. Accompanying this, an acceleration motion and a deceleration motion on a turning circle are added before and after the turning motion. In this application example, as shown in FIG. 2B, there is no stop section when the X-ray source 10 and the X-ray camera 20 shift from turning motion to moving motion. This eliminates extra stops and extra pivoting motions, allowing the X-ray source 10 and X-ray camera 20 to move more quickly from one pivot circle to the next.

In addition, in this application example, as shown in FIG. 3, the locus of movement when moving from the n-th turning circle Cn to the (n+1)-th turning circle Cn+1 is the n-th turning circle Cn and the (n+1)-th turning circle Cn. A trajectory that smoothly connects Cn+1 at the turn end point and the turn start point is generated, and a movable trajectory during movement is used. As a result, the X-ray source 10 and the X-ray camera 20 can be moved more quickly without excessive acceleration or impact.

The movement trajectory that smoothly connects the turning end point and the turning starting point is such that the speed, acceleration, and movement range of the X-ray source 10 and the X-ray camera 20 do not exceed the allowable limits. There is a need.

In this application example, in order to obtain a movement trajectory that does not exceed the allowable limit of the movement range, as shown in FIG. A movement trajectory is designed using a curve (cubic Bezier curve) obtained by designating four points. According to the movement trajectory generation shown in FIG. 4, control vectors can be intuitively set so as not to deviate from the allowable limits (positional restrictions) of the movement ranges of the X-ray source 10 and the X-ray camera 20 . According to this, it is possible to obtain a curved movement trajectory that smoothly connects the turn end point and the turn start point without deviating from the control vector set according to the allowable limit of the movement range.

By the way, even if the movement trajectory can be obtained for each of the X-ray source 10 and the X-ray camera 20 as described above, the movement time suitable for satisfying the permissible values of the velocity and acceleration at the end point of the movement trajectory is X The radiation source 10 and the X-ray camera 20 may differ. On the other hand, in order to eliminate the stop interval in the transition from turning motion to moving motion, the times at which the X-ray source 10 and the X-ray camera 20 each reach the end point of the moving trajectory (that is, the starting point of the next turning circle) must be synchronized. must have been

For this reason, in this application example, for each of the X-ray source 10 and the X-ray camera 20, a suitable travel time that does not deviate from the restricted range of speed and acceleration is calculated, and the longer travel time is calculated. It was decided to adopt the moving time of the movable member of 1 as the common moving time. That is, of the X-ray source 10 and the X-ray camera 20, the movable member whose calculated movement time is shorter (that is, reaches the end point of the movement trajectory earlier) actually has a movement time equal to that of the other movable member. It is controlled to reach the end point of the movement trajectory in the same movement time. Specifically, speed control is performed so that the target speed at the end point of the movement trajectory can be achieved while reducing the speed during movement in order to match the movement time to the end point of the movement trajectory with that of the other movable member. done. In this application example, the rated speed of the servo motor is used as the speed limit. A travel time obtained based on speed may be used as a common travel time.

Here, based on FIG. 14, the flow of the processing described above will be described. FIG. 14 is a flow chart showing the flow of processing related to the synchronous movement of the X-ray source 10 and the X-ray camera 20 performed in the X-ray inspection apparatus 1. As shown in FIG. As shown in FIG. 14, in the X-ray inspection apparatus 1, movement trajectories defined by polynomials are first calculated for each of the X-ray source 10 and the X-ray camera 20 (S101). Next, for each of the X-ray source 10 and the X-ray camera 20, a suitable moving time is calculated so as not to deviate from the limited range of speed and acceleration (S102), and the moving member having the longer calculated moving time is calculated. is determined as the common travel time (S103). Then, movement control of the X-ray source 10 and the X-ray camera 20 is performed so that the movement trajectory calculated in this way is moved within the common movement time (S104).

According to this application example as described above, in an X-ray inspection apparatus having a plurality of movable parts including the X-ray source 10 and the X-ray camera 20, an appropriate moving range of each movable member that does not deviate from the allowable limit is obtained. A movement trajectory can be generated. In addition, each movable member is moved so that the speed at the end point of the movement trajectory of each movable member becomes a predetermined target speed (that does not deviate from the allowable limit), and the time when the plurality of movable members reach the end point of the movement trajectory is synchronized. Control to move can be realized.

As shown in the application example, the present invention can be applied to an X-ray inspection apparatus 1 in which an object S to be inspected is fixed and the X-ray source 10 and the X-ray camera 20 are rotated above and below it. It is also possible to apply to an X-ray inspection apparatus in which the radiation source 10 is fixed and the X-ray camera 20 and the object S to be inspected are rotated.

<Example 1>
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments for carrying out the present invention will be exemplarily described in detail below based on examples with reference to each drawing (including the drawings once described in the application example above). However, the specific configurations described in this embodiment are not intended to limit the scope of the present invention only to them, unless otherwise specified.

An X-ray inspection apparatus 1 according to the first embodiment of the present invention is, for example, an apparatus for judging the soldering state of electronic components soldered to a printed circuit board and the quality of bumps of a ball grid array (BGA). More specifically, X-ray imaging is performed multiple times while the X-ray source and the object to be inspected are relatively moved, the internal state of the inspection target location is acquired, and a cross-sectional image is generated at an appropriate position. Then, the quality is inspected based on the cross-sectional image.

(Device configuration)
FIG. 1 shows a layout diagram of an X-ray source 10, a holding section 40 for holding an inspection object S, and an X-ray camera 20 in an X-ray inspection apparatus 1 according to Embodiment 1 of the present invention. In the X-ray inspection apparatus 1, three-dimensional data is obtained by capturing X-ray images at a plurality of imaging positions for each inspection point on the inspection object S conveyed by a conveying roller (not shown) and held by the holding unit 40. get. Specifically, the X-ray source 10 irradiates the object S to be inspected with X-rays, and the X-ray camera 20 captures an X-ray image of transmitted light. Both the X-ray source 10 and the X-ray camera 20 are movable by a stage (not shown). The X-ray source 10 and the X-ray camera 20 are moved on turning circles 121 and 122 by these stages, respectively, and imaging is performed at a plurality of positions on the turning circles.

Control of each section in the X-ray inspection apparatus 1 is performed based on a control signal from the control section 100 . The X-ray inspection apparatus 1 includes a camera XY stage controller 101 , a camera controller 102 , and an X-ray source XY stage controller 107 as a controller 100 . In addition, a height measurement unit 103, an inspection target position control unit 104, an X-ray source control unit 105, and an imaging height control unit 106 are provided. Furthermore, the X-ray inspection apparatus 1 includes a calculation unit 111 , a main storage unit 112 , an auxiliary storage unit 113 , an input unit 114 and an output unit 115 .

The camera XY stage control unit 101 transmits control signals for driving the camera XY stage (not shown) and moving the X-ray camera 20 in the horizontal direction. The camera control unit 102 transmits a control signal for capturing an X-ray image with the X-ray camera 20 . The height measurement unit 103 receives a signal from the displacement meter 30 and measures the height of the inspection point of the inspection object S. The inspection object position control unit 104 transmits a control signal to the conveying roller and the holding unit 40 of the inspection object S, and controls the horizontal and vertical positions of the inspection object S to the optimum positions for photographing.

The X-ray source control unit 105 transmits a signal for starting and ending X-ray irradiation by the X-ray source 10 and for adjusting the X-ray intensity. The imaging height control unit 106 transmits signals for height control of the X-ray source 10 and the X-ray camera 20 . The X-ray source XY stage control unit 107 transmits signals for driving the X-ray source XY stage (not shown) and moving the X-ray source 10 in the horizontal direction. Signals output from camera XY stage controller 101, camera controller 102, inspection object position controller 104, X-ray source controller 105, imaging height controller 106, and X-ray source XY stage controller 107 are calculated. It is determined based on the calculation result of the unit 111 and the information stored in the main storage unit 112 and the auxiliary storage unit 113 .

As will be described later, the calculation unit 111 includes functional modules of a trajectory calculation unit 111a, a travel time calculation unit 111b, a common travel time determination unit 111c, and an acceleration calculation unit 111d. Information such as setting information and inspection results is exchanged with the user via the input unit 114 and the output unit 115 .

The X-ray camera 20 is a two-dimensional X-ray detector that detects X-rays emitted from the X-ray source 10 and transmitted through the object S to be inspected. As the X-ray camera 20, an I.D. I. (Image Intensifier) tube or FPD (Flat Panel Detector) can be used. Although only one X-ray camera 20 is employed here, a plurality of X-ray cameras may be used.

The displacement meter 30 measures the distance to the object S to be inspected at a plurality of positions on the object S to be inspected. Therefore, it is possible to measure the warpage and inclination of the object S to be inspected by the displacement meter 30 . During the manufacturing process of the inspected object S, warping and tilting may occur, and the amount varies depending on the individual. Therefore, the warpage and inclination of each object S to be inspected are measured, and the height position of the holding unit 40 is adjusted so that appropriate X-ray imaging can be performed.

With the above configuration, the X-ray inspection apparatus 1 can control the positions of the X-ray source 10 and the X-ray camera 20 so that the board can be imaged from various directions. In this embodiment, based on the imaging results from various directions as described above, three-dimensional data of the inspected portion of the object S to be inspected is generated using a three-dimensional data generating method called CT (Computed Tomography). .

Note that a general general-purpose arithmetic unit called a CPU (Central Processing Unit) can be used as the arithmetic unit 111 . A memory such as a RAM can be used as the main storage unit 112 . Auxiliary storage unit 113 can use a ROM, an HDD, or the like. The input unit 114 is any device such as a keyboard, button, switch, mouse, etc., through which a user can input instructions to the calculation unit 111 . The output unit 115 is an arbitrary device, such as a display and a speaker, capable of presenting the output from the calculation unit 111 to the user through video, audio, or the like. That is, these functions can be realized using a general computer system. By reading and executing the program stored in the auxiliary storage unit 113 by the calculation unit 111, each function module of the trajectory calculation unit 111a, the travel time calculation unit 111b, the common travel time determination unit 111c, and the acceleration calculation unit 111d performs X Movement control of the radiation source 10 and the X-ray camera 20 is performed. Note that the calculation unit 111 in this embodiment is capable of parallel calculation, and may include a plurality of CPUs, or may include a plurality of parallel calculation functions in one CPU.

Here, as shown in FIG. 1, the X-ray source 10 and the X-ray camera 20 are controlled by a turning circle 121 based on control signals from the X-ray source XY stage controller 107 and the camera XY stage controller 101, respectively. , 122 and X-ray images are taken at a plurality of positions on the trajectory. By making a turning motion on the turning circles 121 and 122 with respect to each inspection point on the object to be inspected S, it is possible to create a three-dimensional image of the inspection point. When the object S to be inspected is to be inspected, since there are a plurality of positions to be inspected, the X-ray source 10 and the X-ray camera 20 are rotated once over 360 degrees (also referred to as the n-th rotation). ) to acquire an X-ray image of the inspection location, the robot moves to a position where the next inspection location can be imaged. Then, from that position, the next 360-degree turning movement (also referred to as n+1-th turning movement) is started.

(Calculation of movement trajectory)
FIG. 2 shows the trajectory of the movable member when the movable member that hits the X-ray source 10 or the X-ray camera 20 makes the n-th turning motion, moves, and then makes the (n+1)-th turning motion. At that time, according to the prior art, as shown in FIG. 360 degrees) is completed, deceleration motion is performed and then stopped. After that, movement is performed along a predetermined trajectory. This is because, during the turning motion of the movable member, it is necessary to perform a uniform circular motion at high speed in order to obtain high-quality X-ray images at high speed.

Similarly, after the moving movement of the movable member is completed and stopped, the accelerating movement is performed again, and the movable member is accelerated to a predetermined speed before reaching the starting point of the turning movement, and then the n+1th turning movement. (360 degrees) is started. In other words, the movable member provides a deceleration braking distance and temporarily stops after imaging in the n-th turning motion is completed, performs a movement accompanied by acceleration and deceleration in preparation for the (n+1)-th turning, and stops after moving. After that, it accelerates along the turning trajectory so that n+1 shots can be taken. As described above, in the conventional control, it is necessary to stop the movable member and to rotate the movable member for acceleration and deceleration before and after the stop.

In contrast, in the present embodiment, as shown in FIG. 2B, there is no stop section during the movement from the n-th turning motion to the (n+1)-th turning motion, and in addition to the turning motion for taking the X-ray image, In addition, it was decided not to perform turning motion for acceleration/deceleration before and after stopping. Further, the trajectory of the moving motion is a curve that smoothly connects the turning circle of the n-th turning motion and the turning circle of the (n+1)-th turning motion at the turning end point and turning start point. Then, in this embodiment, the trajectory calculator 111a derives such a movement trajectory as a polynomial using a mathematical method. More specifically, a Bezier curve obtained by using a start point, an end point, and two control points (all of which are specified as three-dimensional coordinates) as input information is calculated as the trajectory of the movement of the movable member. Hereinafter, the movement trajectory of the movable member calculated in this manner is also referred to as a specific movement trajectory.

FIG. 4 shows a diagram for explaining the specific movement trajectory calculated by the trajectory calculator 111a. In FIG. 4, the start point P1 is, for example, the end point of the n-th orbital movement of the movable member, and the end point P4 is the start point of the (n+1)th orbital movement. Control points P2 and P3 are then set to provide a control vector between the start point P1 and the end point P4. That is, a control vector 1 is given as a line segment connecting the start point P1 and the control point P2, and a control vector 2 is given as a line segment connecting the control point P3 and the end point P4. Since the specific movement trajectory is determined as a curve that does not deviate from these control vectors 1 and 2, the user can determine the specific movement trajectory from the viewpoint of the space of the X-ray inspection apparatus 1, the range of motion of each XY stage, etc. It is possible to intuitively and easily design a curve that does not deviate from the restricted range of movement.

(Calculation of travel time)
Here, the trajectory that smoothly connects the turning circle of the n-th turning motion and the turning circle of the (n+1)-th turning motion is a trajectory in which the linear velocity of the movable member is continuous at the turning end point and/or the turning start point. may Alternatively, it is desirable that the trajectory is such that the linear velocity and acceleration of the movable member are continuous at the turning end point and/or turning starting point. Also, when the acceleration is continuous, it is ideal that the acceleration is 0.

The movement time calculation unit 111b calculates the suitable movement when moving from the start point to the end point on the specific movement trajectory for each of the X-ray source 10 and the X-ray camera 20 while satisfying such speed and acceleration conditions. Calculate the time (entire orbit moving time) Te. Various methods can be adopted as a method for calculating such travel time.

For example, input information includes the speed (target initial speed) that the movable member should maintain at the start point of the specific movement trajectory and the speed (target terminal speed) that the movable member should maintain at the end point of the specific movement trajectory. , and the required time when connecting them at a constant acceleration can be set as the movement time Te. FIG. 5 is an explanatory diagram showing the relationship between the velocity, acceleration, and elapsed time of the movable member in such a case.

Further, for example, on the condition of maximum acceleration constraint Amax provided for each movable member (or movable axis included in the movable member), the maximum acceleration Amax and the maximum acceleration on the trajectory generated by giving the provisional movement time. It can be obtained by a simulation calculation in which the travel time at which the difference is 0 is taken as the travel time Te. Specifically, the movement time Te is searched for by a simulation using the target initial velocity, the target terminal velocity, and the tentative movement time as input information. Since the trajectory length from the start point to the end point of the specific movement trajectory is fixed, the acceleration corresponding to time and position can be obtained based on the above input information. FIG. 6 shows simulation results of the position, velocity, acceleration, and jerk of the movable member when the temporary movement time (Te) is 0.74 seconds.

Here, the maximum acceleration constraint Amax can also be said to be the target acceleration refAcc for minimizing the movement time Te of the movable member. When the target acceleration is refAcc, the target terminal velocity is refVelEnd, the target initial velocity is refVelStart, and the remaining trajectory length to the end point of the specific movement trajectory is resLen, the target acceleration is expressed by the following formula: refAcc=(refVelEnd ² -refVelStart ² )/ (2×res
Len) (1)
It may be obtained by Note that the target acceleration here corresponds to the restricted target acceleration.

Alternatively, the target initial velocity and the target terminal velocity are set to be the same for each movable part, and the target acceleration is set to 0 m/s^2 (i.e., the velocity is kept constant) to obtain the movement time required to move along the specific movement trajectory. good. FIG. 7 shows an example of simulation when the target initial velocity and target terminal velocity are 0.7 m/s and the target acceleration is 0 m/s^2. FIG. 7A is a diagram showing the trajectory of a specific movement trajectory connecting the n-th turning circle of the movable member and the (n+1)-th turning circle, and FIG. 7B shows the relationship between the speed and movement time of the specific movement trajectory of the movable member. graph.

The travel time calculator 111b thus calculates the travel time Ten for each of the X-ray source 10 and the X-ray camera 20 . FIG. 8 shows the relationship between the movement time and the specific movement trajectory obtained in this manner for the X-ray source 10 and the X-ray camera 20 . FIG. 8A is a diagram showing the trajectory of the specific movement trajectory connecting the n-th turning circle of the X-ray source 10 and the (n+1)-th turning circle, and FIG. It is a graph which shows the relationship of Te1. FIG. 8C is a diagram showing the trajectory of the specific movement trajectory connecting the n-th turning circle of the X-ray camera 20 and the (n+1)-th turning circle. It is a graph which shows the relationship of Te2.

As shown in FIG. 8, the X-ray source 10 has a target initial velocity and a target terminal velocity of 1.4 m/s, and a target acceleration of 0 m/s^2. A simulation result of moving the trajectory was obtained. On the other hand, when the X-ray camera 20 has a target initial velocity and a target terminal velocity of 0.7 m/s and a target acceleration of 0 m/ŝ2, the travel time Te2 is 1.066 seconds. The results were obtained.

(Determination of Common Travel Time)
Here, although the calculated movement times of the X-ray source 10 and the X-ray camera 20 are different, the X-ray source 10 and the X-ray camera 20 each reach the end point of the movement trajectory (that is, the start point of the next turning circle). must be synchronized. Therefore, the common travel time determination unit 111c performs processing for determining one common travel time Tec that is applied to both the X-ray source 10 and the X-ray camera 20. FIG. Specifically, of the movement time Te1 of the X-ray source 10 and the movement time Te2 of the X-ray camera 20, the longer one, here the movement time Te2 of the X-ray camera 20 requiring 1.066 seconds, is used as the common movement. Determine the time (common total trajectory travel time) Tec.

(Movement control command)
When the control unit 100 (camera XY stage control unit 101, X-ray source XY stage control unit 107) performs movement control of the X-ray source 10 and the X-ray camera 20, the X-ray source 10, the X-ray Control is performed to move each of the cameras 20 from the start point to the end point of the specific movement trajectory at the common movement time Tec. At this time, the X-ray source 10 has a specific In the middle of the movement on the movement trajectory, the speed will be reduced and the movement will be performed.

FIG. 9 shows the relationship between the movement time/speed of the X-ray source 10 and the specific movement trajectory when moving with the common movement time Tec of 1.066 seconds. FIG. 9A is a diagram showing the trajectory of the specific movement trajectory connecting the n-th turning circle of the X-ray source 10 and the (n+1)-th turning circle, and FIG. It is a graph which shows the relationship of time. As shown in FIG. 9, the target initial velocity and target terminal velocity of the X-ray source 10 are 1.4 m/s. It becomes necessary to reduce the

(Modification during movement control execution)
As described above, it is possible to calculate the moving speed and moving time of each movable member by simulation in advance, and perform control based on this. However, if a certain movable member needs to perform an unexpected action such as obstacle avoidance during actual movement control, there arises a problem that all the movable members cannot be synchronized.

For this reason, the movement time calculation unit 111b calculates the remaining trajectory movement time required to reach the end point of the specific movement trajectory so that the target terminal velocity can be achieved for each movable member based on the current position of the movable member on the specific movement trajectory. This process is executed every predetermined control cycle. Then, the common movement time determination unit 111c determines the longest remaining trajectory movement time as the common remaining trajectory movement time among the remaining trajectory movement times for each movable member calculated in each control cycle, and determines the common movement time. And a process of updating the common remaining track travel time determined in the immediately preceding control cycle is executed in each control cycle. Then, the control unit 100 (the camera XY stage control unit 101 and the X-ray source XY stage control unit 107) controls the X-ray source 10 and the X-ray camera 20 with the latest common remaining trajectory movement time determined for each control cycle. movement control. By doing so, the common movement time is updated in real time, and even if a situation arises in which it is not possible to reach the end point of the specific movement trajectory within the initially given movement time, each movable member can be synchronized to reach the target. The terminal velocity can be feasibly movement controlled.

By the way, it takes time to search for the travel time that satisfies the maximum acceleration constraint for all movable members, and it is not realistic to continue calculating the travel time while performing such searches in real time. On the other hand, in order to achieve synchronization in real time, even if the movement time Te is not fixed, all the movable members need only have a common remaining track movement time from the present time. Therefore, the travel time calculation unit 111b calculates the time required for connecting the current speed and the target terminal speed of each movable member at a constant acceleration as the remaining track travel time. Here, for each of the plurality of movable members, the acceleration calculation unit 111d calculates a target acceleration (the above constant acceleration) for reaching the end point of the specific movement trajectory so that the target terminal velocity can be achieved in the common remaining trajectory movement time. calculate.

FIG. 10 is an explanatory diagram showing the relationship between the speed of the movable member and the elapsed time when calculating the remaining track movement time in this way. As shown in FIG. 10, the target acceleration refAcc here is obtained by the following equation using the current velocity actVel of the movable member, the target terminal velocity refVelEnd, and the remaining trajectory length resLen until reaching the end point of the specific movement trajectory. refAcc=(refVelEnd2-actVel2)/(2*resLen) (2)
sought by That is, the remaining trajectory travel time is calculated by using the current velocity of the movable member, the target terminal velocity, and the remaining trajectory length until reaching the end point of the specific travel trajectory.

(Suppression of track terminal acceleration)
Note that when the movement time is dynamically changed, the acceleration at the end point of the specific movement trajectory becomes too large to satisfy the target terminal velocity, and is discontinuous with the acceleration (0 m/s^2) during the next turning movement. There is a risk of becoming Since this is not desirable from the viewpoint of the load on the device and the quality of the captured image, it is necessary to suppress the acceleration at the end point of the movement trajectory when the remaining trajectory movement time is changed.

Therefore, the acceleration calculation unit 111d performs calculation using a predetermined correction coefficient when calculating the target acceleration, increases the speed of the movable member in advance, and gently decreases the acceleration near the end point of the specific movement trajectory. calculates a possible target acceleration. Specifically, the target acceleration is accRefNonLimited, the target terminal velocity is refVelEnd, the current velocity of the movable member is actVel, the common remaining trajectory movement time is tLeft, and the specific movement trajectory is set so that the target terminal velocity can be achieved with the common remaining trajectory movement time. The following formula accRefNonLimited=(Vnec-actVel+α×(Vnec-refVelEnd))/tLeft (3)
The target acceleration can be calculated by

The required speed Vnec is obtained by the following formula Vnec=2×resLen/tLeft-actVel (4)
can be obtained by

FIG. 11 shows an explanatory diagram relating to calculation of the target speed when the correction coefficient α is set to "3". FIG. 12A is an explanatory diagram showing the speed change of the movable member when the correction coefficient α is set to "1", and FIG. 12B is an explanatory diagram showing the speed change of the movable member when the correction coefficient α is set to "3". respectively.

As shown in FIG. 12, when the correction coefficient is 1 (when no correction is performed in calculating the target acceleration), the reduced speed begins to rise in the latter half of the movement time, and the target terminal speed is achieved. Furthermore, it can be seen that the acceleration cannot be reduced even near the end point of the moving trajectory. On the other hand, when the correction coefficient is set to 3, the reduced speed begins to rise from the first half of the movement time, and it can be seen that the acceleration can be smoothly reduced near the end point of the movement trajectory.

(Current position calculation of moving part)
Note that, as described above, in order to calculate the remaining track movement time, the position information of the movable member (on the specific movement track) for each control cycle is required. Below, based on FIG. 13, the processing for obtaining the position of the movable member for each such control period will be described. FIG. 13 is a block diagram showing the flow of information processing for calculating the current position of the movable member.

As shown in FIG. 13, first, in the commanded acceleration calculation module 301, the remaining trajectory length resLen, the remaining travel time tLeft, the target terminal velocity refVelEnd, the current velocity actVel, and the acceleration correction coefficient α are input, and the commanded (target) acceleration before constraint is calculated. accRefNonLimited is calculated. Subsequently, in the commanded acceleration upper/lower limit module 302, it is determined whether or not the commanded acceleration before constraint deviates from predetermined upper/lower limits. Here, if the upper and lower limits are not exceeded, the pre-restricted commanded acceleration is determined as the commanded acceleration accRef. On the other hand, if the pre-constraint commanded acceleration deviates from the upper and lower limits, the deviating limit value is determined as the commanded acceleration.

Next, in the command speed calculation module 303, the command acceleration accRef, the current speed actVel, and the predetermined control cycle Ts are input, and the pre-restricted command speed velRefNonLimited is calculated. Subsequently, in the speed upper/lower limit module 304, it is determined whether or not the pre-restricted commanded speed is within predetermined upper/lower limits. Here, if the upper and lower limits are not exceeded, the pre-restriction command speed is determined as the command speed velRef. On the other hand, if the pre-restriction command speed deviates from the upper and lower limits, the deviating limit value is determined as the command speed.

Next, in the control period movement amount calculation module 305, the control period period movement amount (delta L) is calculated by inputting the command speed velRef and the control period Ts. Then, in the Bezier curve parameter increase amount calculation module 306, the amount of movement during the control period and the Bezier curve parameter value R are input, and the Bezier curve parameter increase amount (delta R) is calculated. Then, a Bezier curve parameter value R is calculated in the Bezier curve parameter value calculation module 307 .

Here, the Bezier curve parameter value R satisfies 0≦R≦1. Referring to FIG. The variable value R will increase. Then, if the amount of movement during the control cycle is known, the amount of increase in the parameter value R corresponding to it can also be calculated.

Then, the Bezier curve calculation module 308 uses the Bezier curve parameter value R obtained in this way and the coordinates (or control vectors) of the start point P1, the end point P4, and the control points P2 and P3 as inputs to calculate the movable member. A position P is obtained for each control cycle.

According to the X-ray inspection apparatus 1 shown in the present embodiment as described above, it is possible to intuitively design the movement trajectory of the movable member without departing from the movement range, and to control the speed of the connection point between the turning movement and the movement movement. Synchronous control of a plurality of movable members can be realized while maintaining the same. Also, synchronous control of a plurality of movable members can be executed in real time without a prior trajectory generation process. Therefore, it is possible to improve the inspection speed while reducing the load on the apparatus.

<Others>
The above description of the embodiments is merely illustrative of the present invention, and the present invention is not limited to the above specific forms. Various modifications and combinations are possible for the present invention within the scope of its technical idea. For example, in the present embodiment, the X-ray inspection apparatus 1 has a configuration that also serves as a control system. I don't mind. Also, the configuration may be such that the components of the control system are distributed among a plurality of terminals.

Further, in the above embodiment, the acceleration calculation unit 111d uses the correction coefficient to calculate the target acceleration, but it is not necessary to calculate the target acceleration using such a formula. For example, if the target acceleration is accRefNonLimited, the target terminal velocity is refVelEnd, the current velocity is actVel, the common remaining trajectory movement time is tLeft, and the required velocity is Vnec, then the following formula accRefNonLimited=(2×Vnec−refVelEnd−actVel)/ tLeft (5)
The target acceleration may be calculated by

In each of the above examples, the movement trajectory of the movable member is a Bezier curve, but it may be another curved trajectory defined using a polynomial, such as a clothoid curve. Further, in each of the above examples, the common movement time is determined according to the longest movement time among the movement times of the movable members, but the method of determining the common movement time is not limited to this. For example, within the permissible range of the device, the earliest travel time may be adopted, or the average value or median value of a plurality of travel times may be used as the common travel time.

Further, in the above-described embodiment, before starting movement control of the device, the movement time was calculated by simulation based on the starting point of the specific same trajectory. , the movement time may be calculated using the current position and current speed of the movable member as input information. That is, at the starting point of the specific movement trajectory, the process of calculating the movement time with the total length of the specific movement trajectory as the remaining trajectory length may be performed, and the movement control may be executed.

In addition, although the X-ray inspection apparatus has been described as an example in each of the above examples, the present invention can naturally be applied to various apparatuses other than this.
Control) can also be preferably applied to machine tools.

<Appendix 1>
A control system (1) for a device comprising a plurality of movable members (10, 20), comprising:
movement trajectory calculation means (111a) for calculating, for each of the plurality of movable members, a specific movement trajectory, which is a path connecting a start point and an end point relating to movement of the movable member and is specified using a polynomial;
The time required for each of the plurality of movable members to move from one point on the specific movement trajectory to the end point, and the movement that allows the movable member to achieve a target terminal velocity, which is a predetermined speed to be maintained at the end point. Travel time calculation means (111b) for calculating time;
common travel time determination for determining one common travel time that enables each of the plurality of movable members to achieve the target terminal velocity at the end point based on the plurality of travel times calculated for each of the plurality of movable members; means (111c);
a control command means (100) for causing the device to execute control including speed control for moving each of the plurality of movable members from the one point on each of the specific movement trajectories to the end point in the common movement time; have a
A control system characterized by:

<Appendix 2>
A control method for a device comprising a plurality of movable members, comprising:
a movement trajectory calculating step (S101) for calculating, for each of the plurality of movable members, a specific movement trajectory, which is a path connecting a start point and an end point of movement of the movable member and is specified using a polynomial;
The time required for each of the plurality of movable members to move from one point on the specific movement trajectory to the end point, and the movement that allows the movable member to achieve a target terminal velocity, which is a predetermined speed to be maintained at the end point. a travel time calculation step (S102) for calculating the time;
common travel time determination for determining one common travel time that enables each of the plurality of movable members to achieve the target terminal velocity at the end point based on the plurality of travel times calculated for each of the plurality of movable members; a step (S103);
a control command step (S104) for causing the device to execute control including speed control for moving each of the plurality of movable members from the one point on each of the specific movement trajectories to the end point in the common movement time (S104); have a
A control method characterized by:

DESCRIPTION OF SYMBOLS 1, 11... X-ray inspection apparatus 10... X-ray source 20... X-ray camera 30... Displacement meter 40... Holding part 100... Control part 111... Calculation part 111a. Trajectory calculator 121 X-ray source turning movement turning circle 122 X-ray camera turning movement turning circle 123 Moving movement trajectory S Object to be inspected (substrate)

Claims (17)

A control system for a device comprising a plurality of movable members, comprising:
movement trajectory calculation means for calculating, for each of the plurality of movable members, a specific movement trajectory that is a path connecting a start point and an end point related to movement of the movable member and is specified using a polynomial;
The time required for each of the plurality of movable members to move from one point on the specific movement trajectory to the end point, and the movement that allows the movable member to achieve a target terminal velocity, which is a predetermined speed to be maintained at the end point. travel time calculation means for calculating time;
common travel time determination for determining one common travel time that enables each of the plurality of movable members to achieve the target terminal velocity at the end point based on the plurality of travel times calculated for each of the plurality of movable members; means and
and control command means for causing the device to execute control including speed control for moving each of the plurality of movable members from the one point on each of the specific movement trajectories to the end point in the common movement time. there is
A control system characterized by: The common travel time determination means,
2. The control system according to claim 1, wherein the longest moving time among the plurality of moving times calculated for each of the plurality of movable members is determined as the common moving time. The movement time calculation means calculates a remaining track movement time required for each of the plurality of movable members to reach the end point from the current position at each predetermined control cycle during movement control of the movable member,
The common movement time determining means determines and updates one common remaining track movement time for each control cycle based on the remaining track movement time for each movable member calculated for each control cycle;
The control command means controls the device to move each of the plurality of movable members from the current position to the end point with the latest common remaining track movement time updated every control cycle. let
3. A control system according to claim 1 or 2, characterized in that: The movement time calculation means uses the current velocity of the movable member, the target terminal velocity, and the remaining trajectory length from the current position of the movable member to the end point of the specific movement trajectory to move the remaining trajectory. calculate the time,
4. The control system according to claim 3, characterized in that: Acceleration for calculating a target acceleration or a target jerk for each of the plurality of movable members to reach the end point of the specific movement trajectory so as to achieve the target terminal velocity in the common remaining trajectory movement time for each of the control cycles. further comprising calculating means;
The control command means causes the device to execute movement control that satisfies the target acceleration or the target jerk calculated for each of the control cycles for each of the plurality of movable members.
5. A control system according to claim 3 or 4, characterized in that: The acceleration calculation means is
accRefNonLimited for the target acceleration, refVelEnd for the target terminal velocity, actVel for the current velocity of the movable member, tLeft for the common remaining trajectory movement time, and tLeft for the common remaining trajectory movement time, and the specific movement trajectory for realizing the target terminal velocity with the common remaining trajectory movement time. When the speed required to reach the end point of is Vnec,
accRefNonLimited=(2*Vnec-refVelEnd-actV
el)/tLeft
Calculate the target acceleration by the formula of
6. The control system according to claim 5, characterized in that: The acceleration calculation means uses a predetermined acceleration correction coefficient α to
accRefNonLimited for the target acceleration, refVelEnd for the target terminal velocity, actVel for the current velocity of the movable member, tLeft for the common remaining trajectory movement time, and tLeft for the common remaining trajectory movement time, and the specific movement trajectory for realizing the target terminal velocity with the common remaining trajectory movement time. When the speed required to reach the end point of is Vnec,
accRefNonLimited=(Vnec−actVel+α×(Vnec−refVelEnd))/tLeft
Calculate the target acceleration by the formula of
6. The control system according to claim 5, characterized in that: the acceleration calculating means outputs the limit value as the target acceleration or the target jerk when the calculated target acceleration or the target jerk exceeds a predetermined limit value;
8. A control system according to any one of claims 5 to 7, characterized in that: 9. The control system according to any one of claims 3 to 8, characterized in that said common remaining orbit moving time is determined as a value that is an integral multiple of said control period. The movement time calculation means calculates a total trajectory movement time, which is a movement time from the start point to the end point of the specific movement trajectory, for each of the plurality of movable members before movement control of the movable members,
The common travel time determination means determines one common total track travel time based on a plurality of the total track travel times calculated for each of the plurality of movable members.
10. A control system according to any one of claims 1 to 9, characterized in that: The travel time calculation means is
The movable member moves on the specific movement trajectory from the start point to the end point using at least a target initial speed, which is a predetermined speed that the movable member should maintain at the start point, and the target terminal speed as input information. the time during which the acceleration from the target initial velocity to the target terminal velocity is constant is calculated as the movement time;
11. The control system of claim 10, wherein: The travel time calculation means is
The target initial velocity, the target terminal velocity, and an acceleration limit, which is a limit value of the acceleration until the movable member reaches the target terminal velocity from the target initial velocity, as input information, and an acceleration that does not exceed the limit acceleration. calculating the travel time by looking up the travel time at
12. The control system of claim 11, wherein: Let the limited acceleration be a limited target acceleration refAcc until the movable member reaches the target terminal speed from the target initial speed, the target terminal speed be refVelEnd, the target initial speed be refVelStart, and reach the end point of the specific movement trajectory. refAcc=(refVelEnd ² -refVelStart ² )/(2×resLen), where resLen is the remaining trajectory length of
13. A control system according to claim 12, characterized in that: 14. Control system according to any one of the preceding claims, characterized in that the polynomials represent Bezier curves or clothoid curves. The apparatus includes an X-ray source that generates X-rays to irradiate an object to be inspected, an X-ray camera that captures an X-ray image of the X-rays irradiated from the X-ray source to the object to be inspected, and the object to be inspected. An X-ray inspection apparatus comprising a holding unit for
The plurality of movable members include at least any two or more of the X-ray source, the X-ray camera, and the holding section.
15. A control system according to any one of claims 1 to 14, characterized in that: A control method for a device comprising a plurality of movable members, comprising:
a movement trajectory calculating step of calculating, for each of the plurality of movable members, a specific movement trajectory that is a path connecting a start point and an end point related to movement of the movable member and is specified using a polynomial;
The time required for each of the plurality of movable members to move from one point on the specific movement trajectory to the end point, and the movement that allows the movable member to achieve a target terminal velocity, which is a predetermined speed to be maintained at the end point. a travel time calculation step of calculating the time;
common travel time determination for determining one common travel time that enables each of the plurality of movable members to achieve the target terminal velocity at the end point based on the plurality of travel times calculated for each of the plurality of movable members; a step;
and a control command step for causing the device to execute control including speed control for moving each of the plurality of movable members from the one point on each of the specific movement trajectories to the end point in the common movement time. there is
A control method characterized by: A program for causing a computer to perform the steps of the method of claim 16.

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