JP2008049459A - System, method and program for controlling manipulator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely hold and move an object to be held while preventing the object to be held from being slipped from a manipulator when the manipulator holds the object to be held having an unknown weight and without being broken even when the object to be held is brittle. <P>SOLUTION: The manipulator operation support system is equipped with a material measured in a noncontact manner with a component analyzer 13 provided on a holding part 10 of the manipulator 11, a three-dimensional data measured in a noncontact manner with a shape measuring sensor 14 provided on the holding part 10, a PC42 for processing a shape measurement which calculates the weight of the object A based on the data of a body information database 43b, and calculates a holding force for holding the object A by the holding part 10 from the weight of the object A to be calculated, and a PC41 for controlling for operating the manipulator 11 with the holding force obtained by the PC 42 for processing the shape measurement. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a manipulator control system, a manipulator control method, and a program for gripping and moving a gripping object with a manipulator.

  Manipulators are used to hold an object that cannot be operated by being directly grasped by a hand, instead of the person, to move or operate the object.

  When working with a manipulator, the object to be grasped is often specified, and information such as the object shape, weight, grasping position, necessary grasping force, and object installation position is treated as known. There are many.

  When the installation position and shape of the gripping object are unknown, the gripping position and posture can be corrected by measuring the installation position and shape of the target object in combination with an image processing system or a measurement system that replaces it.

  Conventionally, as a method of appropriately adjusting the gripping force of the manipulator when the weight of the gripping object is unclear, for example, the friction coefficient is estimated from the pressing force and the frictional force by sliding the gripping object within the finger. There is a method for determining the gripping force (see, for example, Patent Document 1).

There is also a method of measuring the amount of slip of an object from the fixed state of the curved elastic body attached to the fingertip of the manipulator and the grasped object and utilizing it for adjusting the grasping force (see, for example, Patent Document 2).
JP-A-2005-144573 JP 2000-254884 A

  In the case of the above-described conventional manipulator object gripping force adjustment method, since the manipulator gripping force adjustment is performed based on the unique information of the gripping object, it is generally possible to perform a gripping operation only on a known object.

  In this case, it is difficult to set information specific to each object in advance when it is assumed that there is no versatility and gripping work of various objects, and the manipulator can also work on an unknown object. It is desirable to be able to respond flexibly so that it can be done.

For this purpose, it is necessary to automatically determine not only the shape of the object to be grasped but also the weight, the grasping position suitable for it, the grasping force, and the like.
The outer shape (shape) of an object can be measured three-dimensionally by conventional techniques such as a stereo viewing technique using a camera and a laser scan measurement technique.

  However, when an object having an unknown shape is handled by performing shape measurement, there is a problem in that an appropriate gripping force cannot be determined because the weight of the object is unknown.

  If the manipulator grips an object with an excessive gripping force during the gripping operation of the object, the object will be crushed. On the other hand, if the gripping force is insufficient, the object may slide down. For this reason, it is important to determine an appropriate gripping force according to the weight of the gripping object.

  Although the techniques found in the prior art described above enable the weight to be estimated and the gripping force to be adjusted appropriately even for a gripping target whose weight is unknown, slipping within the finger after gripping the object is possible. Therefore, if there is a large error in the initial estimated value when it comes into contact with the gripping object, the gripping object slips down due to insufficient gripping force, or conversely excessive gripping force. For this reason, the object may be crushed.

  The present invention has been made to solve such problems. When a manipulator grips a gripping object with an unknown weight with the gripping part, the gripping object does not slide down from the gripping part of the manipulator and is gripped. An object of the present invention is to provide a manipulator control system, a manipulator control method, and a program capable of reliably grasping and moving a fragile object without breaking it.

  In order to solve the above-described problems, a manipulator control system according to the present invention includes a manipulator having a gripping unit for gripping and moving a gripping target, and the gripping target that is provided in the gripping unit and approaches the gripping target A component analyzer that emits light or radiation to measure the material thereof in a non-contact manner, and a three-dimensional shape that is provided in the gripping unit and radiates light or radiation to the gripping object that is approached, without contact. A shape measuring sensor to measure, a volume calculating unit for calculating the volume of the gripping object from the material of the gripping object measured by the component analyzer and the three-dimensional shape measured by the shape measuring sensor, and a known A database in which object information including the shape of the gripping object, substance density information, gripping position, and gripping force is accumulated, and the volume of the gripping object calculated by the volume calculation unit, A weight calculation unit that calculates the weight of the gripping object from the density information of the substance read from the database using the material of the gripping object measured by the component analyzer as a key, and the weight calculation unit that calculates the weight A gripping force calculation unit that calculates a gripping force of the gripping target from the weight of the gripping target, and a control unit that operates the manipulator with the gripping force calculated by the gripping force calculation unit. To do.

  The manipulator control method of the present invention is a manipulator control method for gripping / moving a gripping object by controlling a manipulator having a gripping part for gripping / moving the gripping object, and a component analyzer provided in the gripping part. However, the step of emitting light or radiation to the approaching gripping object and measuring the material thereof in a non-contact manner, and the shape measurement sensor provided in the gripping part is applied to the approaching gripping object. The computer grasps the three-dimensional shape by emitting light or radiation without contact, and the grasping material measured by the component analyzer and the three-dimensional shape measured by the shape measurement sensor. The step of calculating the volume of the object, the calculated volume of the gripping object, and the measured material of the gripping object from the database The computer calculates the weight of the grasped object from the density information of the protruding substance, and the computer grasps the grasped object for the manipulator to grasp the grasped object from the calculated weight of the grasped object. A step of calculating a force; and a step of causing the computer to operate the manipulator with the calculated gripping force.

  The program of the present invention is a program for a computer to control a manipulator having a gripping part for gripping / moving a gripping object, wherein the component analyzer provided in the gripping part is the gripping object. The material measured by non-contact by emitting light or radiation to the object and the three-dimensional measurement measured by the shape measuring sensor provided on the gripping unit without emitting light or radiation to the gripping object A volume calculation unit that calculates the volume of the grasped object from the shape, a database that accumulates object information including the shape of the known grasped object, the density information of the substance, the grasping position, and the grasping force, and the volume calculating unit. The density information of the substance read from the database using the calculated volume of the grasped object and the material of the grasped object measured by the component analyzer as keys. A weight calculation unit that calculates the weight of the gripping object from the weight, a gripping force calculation unit that calculates a gripping force of the gripping object from the weight of the gripping object calculated by the weight calculation unit, and the gripping force It is made to function as a control part which operates the said manipulator with the gripping force calculated by the calculation part.

  That is, in the present invention, when a grasping object with an unknown weight is grasped with a manipulator, the shape and mass of the grasping object are measured in a non-contact manner by emitting light or radiation, and the grasping object is determined from the measurement result and the mass. The weight of the object is obtained by calculation, and an appropriate gripping force for gripping the gripping object is determined, and then the gripping object is gripped by the manipulator. That is, the gripping force of the manipulator is appropriately adjusted in advance with respect to the gripping target whose weight is unknown.

  According to the present invention, when a manipulator grips a gripping object whose weight is unknown, the gripping object does not slide down from the gripping part of the manipulator, and even if the gripping object is fragile, it can be reliably destroyed. Can be gripped and moved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
First, a manipulator work support system that is one embodiment of a manipulator control system will be described with reference to FIG. FIG. 1 is a diagram illustrating a configuration of a manipulator work support system according to the first embodiment.

  The manipulator work support system according to the first embodiment includes a manipulator 11, a manipulator controller 30 connected to the manipulator 11 via a communication cable 20, and a plurality of manipulator controllers 30 connected to the manipulator controller 30 via a network such as a LAN 21. Computer (control computer 41, shape measurement processing computer 42, object information database computer 43, status display computer 44).

  Hereinafter, the computer is referred to as “PC”. Each PC includes a CPU, a ROM, a memory such as a RAM, a storage device such as a hard disk device, an input device such as a mouse and a keyboard, and an output device such as a display and an external interface.

  The hard disk device stores an operating system (hereinafter referred to as “OS”) for operating the CPU, a control program, and the like. The mouse, keyboard, etc. accept various instruction operations by the operator and input the instructions to the CPU.

  The manipulator 11 includes a plurality of joints 11a, 11b, and 11c, arm portions 11d and 11e, a drive portion 11f that drives the joints 11a, 11b, and 11c in each direction, and a grip portion 10 provided at the tip of the arm portion 11e. And have.

  A gripper portion 12 is provided at the tip of the grip portion 10. The gripper unit 12 has a finger-shaped tip 12a for gripping a gripping target A (hereinafter referred to as "target A"), and opens and closes the two tip 12a. A can be gripped or released. The gripper unit 12 is provided with a gripping force measurement sensor (not shown) that measures the gripping force of the distal end portion 12a.

  The grip portion 10 is provided with a six-axis force sensor 15 that measures an external force (force and moment) applied to the tip of the gripper portion 12, that is, the hand. On the six-axis force sensor 15, a component analyzer 13 and a shape measurement sensor 14 are provided toward the tip of the gripper unit 12.

  As the component analyzer 13, for example, a component of the object A is analyzed without touching the object A (without contact) using a radiation or an optical system such as a fluorescent X-ray analyzer or an infrared spectrophotometer. Then, an apparatus that can identify the configuration is used.

  The X-ray fluorescence analyzer is an apparatus that irradiates a measurement object A with X-rays generated from an X-ray tube and receives and analyzes the fluorescent X-rays emitted from the measurement object A. Since the energy of the fluorescent X-ray emitted from the measurement object A has an energy value specific to the element, the type of the element contained in the measurement object is specified by measuring the fluorescent X-ray. It is possible.

  Infrared spectrophotometry device irradiates an object with infrared light, and separates transmitted light, reflected light, or scattered light from the object, and obtains a transmission spectrum, a reflection spectrum, or a diffusion spectrum, respectively. This is a method for obtaining physical property information of an object. The obtained spectrum is peculiar to the substance, so that the constituent material can be identified.

  The shape measurement sensor 14 recognizes a three-dimensional shape (three-dimensional shape) by using, for example, a stereo viewing technique using two CCD cameras or a laser scanning technique. An apparatus for performing laser scanning has a mechanism for measuring a distance from the object A based on a time difference from when the measurement object is irradiated with laser light until the laser light is reflected back to the measurement object. The three-dimensional shape of the object is measured by two-dimensional scanning using direct or mirror reflection. Here, description will be made assuming that a CCD camera is used.

  Note that the types of the component analyzer 13 and the shape measurement sensor 14 are not limited to those exemplified here, and other means may be used for the same purpose. Further, although the 6-axis force sensor 15 is used as an external force measurement sensor, the present invention is not limited to this, and a load cell may be used instead of the 6-axis force sensor 15 depending on the work / operation contents.

  The manipulator controller 30 includes a CPU 31, a memory 32, a control interface 34, a communication interface 35, and the like.

  The memory 32 of the manipulator controller 30 stores motor drivers, control software, and the like for controlling the motors that drive the joints 11a, 11b, and 11c.

  The control interface 34 is an interface for connecting the communication cable 20 to the manipulator controller 30, and transmits a control signal for operating the manipulator 11 to the manipulator 11 through the communication cable 20.

  The control interface 34 receives the measurement data measured by the component analyzer 13 and the shape measurement sensor 14 of the manipulator 11 through the communication cable 20 and passes them to the CPU 31.

  The communication interface 35 is a LAN connection board or the like, and connects the manipulator controller 30 to the LAN 21. The communication interface 35 receives an operation command from the control PC 41 and passes it to the CPU 31.

  The CPU 31 transmits the operation command passed from the communication interface 35 to the manipulator 11 through the control interface 34 as a control signal for the manipulator 11.

  Further, the CPU 31 transmits the measurement data received by the control interface 34 to each PC (control PC 41, shape measurement processing PC 42, object information database PC 43, status display PC 44) from the communication interface 35 through the LAN 21.

  The control PC 41 determines the operation of the manipulator 11 and gives an operation command for each axis to the manipulator controller 30. The control PC 41 displays the determined operation of the manipulator 11 and the operation command of each axis for the manipulator controller 30 on the display 41a.

  The CPU of the control PC 41 calculates the volume of the object A from the material of the object A measured by the component analyzer 13 and the three-dimensional shape (three-dimensional shape) of the object A measured by the shape measurement sensor 14. Functions as a volume calculation unit.

  The CPU of the control PC 41 reads from the object information database 43b of the object information database PC 43 using the volume of the object A calculated by the volume calculation unit and the material of the object A measured by the component analyzer 13 as keys. It functions as a weight calculation unit that calculates the weight of the object A from the density information of the substance.

  The CPU of the control PC 41 functions as a gripping force calculation unit that calculates a gripping force for the manipulator 11 to grip the target A from the weight of the gripping target calculated by the weight calculation unit.

  The CPU of the control PC 41 functions as a control unit that operates the manipulator 11 with the gripping force calculated by the gripping force calculation unit.

  The CPU of the shape measurement processing PC 42 calculates (calculates) three-dimensional shape data of the object A based on the information of the shape measurement result of the object A obtained from the shape measurement sensor 14 of the hand (gripper unit 12). The three-dimensional shape data of the calculation result (calculation result) is displayed on the display 42a.

The object information database PC 43 registers (accumulates) information specific to a known gripping object (three-dimensional shape data, material density information, gripping position, gripping force, weight, center of gravity position, grippable position, etc.). Has an object information database 43b.
The object information database 43b can search related information from one keyword. For example, the density of a substance is obtained using the calculated volume of the gripping object and the material of the gripping object measured by the component analyzer 13 as keys. Information can be read out.

  The CPU of the object information database PC 43 uses a search unit that searches the object information database 43b for data (characteristic data, etc.) of the target object A using the measured shape data of the target object A as a search key, It functions as an output unit that displays (outputs) the data (characteristic data, etc.) of the object A searched by the search unit on the display 43a.

  When the information of the target A does not exist in the object information database 43b as a result of the search by the search unit, the CPU of the object information database PC 43 uses the target A as an unknown object to obtain information (shape) Data, material, etc.) function as a registration unit for additionally registering in the object information database 43b.

  As a result of the search by the search unit, the CPU of the object information database PC 43 determines that the object A is an unknown object when the information on the object A does not exist in the object information database 43b. It functions as a data selection unit that reads data (such as characteristic data) of an object similar to the shape from the object information database 43b and uses the data (such as characteristic data) as data of the object A.

  The CPU of the object information database PC 43 uses the gripping position and the gripping force stored in advance in the object information database 43b (as a key) based on the characteristic data of the similar object that is the object A by the data selection unit. Functions as a gripping force determining unit that determines an appropriate gripping position and gripping force.

  The state display PC 44 obtains a position in the three-dimensional space where the gripping unit 10 of the manipulator 11 grips the object A based on the shape of the object A measured by the shape measurement sensor 14. Then, the state display PC 44 displays the posture of the manipulator 11 and the positional posture relationship between the gripping unit 10 and the object A on the screen of the display 44a in a three-dimensional computer graphic (hereinafter referred to as “CG”).

  The PCs 41 to 44 are connected to the LAN 21 and can transmit and receive information to and from each other. Here, an example is shown in which a PC is installed separately for each process, but the processing functions of each PC may be combined into one PC.

  Next, the operation of the manipulator work support system according to the first embodiment will be described with reference to FIG. FIG. 2 is a flowchart showing the processing operation of the manipulator work support system of the first embodiment.

  In the case of the manipulator work support system according to the first embodiment, the CPU of the control PC 41 performs three-dimensional image processing on the object A by performing image processing on the image obtained from the distal end portion 12a of the gripping portion 10, that is, the CCD camera at the hand. The position (coordinates) in the space is recognized, an instruction for operating the manipulator 11 is sent to the manipulator controller 30, and the manipulator 11 is first operated to move its tip 12 a, that is, the hand to the vicinity of the object A. It moves (step 101 in FIG. 2) and approaches the object A. Note that a step means a processing step, and hereinafter, the step is referred to as “S”.

  At this time, the position (coordinates) of the object A in the rough three-dimensional space may be registered in advance in the object information database 43b, or may be recognized by image processing based on the image of the hand CCD camera. good.

  Next, the three-dimensional shape of the object A is measured by the shape measurement sensor 14 provided at the hand of the manipulator 11 (S102).

  The shape measurement sensor 14 may measure only a part of the object A from a fixed viewpoint with a fixed hand position when performing image processing by stereo vision or measurement by a laser scanning device.

  For this reason, the CPU of the control PC 41 moves the tip of the manipulator 11 so as to go around the object A. Along with this movement, the CPU of the shape measurement processing PC 42 obtains three-dimensional shape data of the object A by synthesizing the measurement results obtained by measuring the appearance of the object A.

  Next, the CPU of the shape measurement processing PC 42 calculates the volume of the object A using the obtained three-dimensional shape data of the object A (S103).

  Since the data obtained by the shape measurement at this time is a measurement point group having three-dimensional position information, the CPU of the shape measurement processing PC 42 generates a solid model having these point groups as surfaces. The method for calculating the volume from the solid model is widely used in three-dimensional CAD and the like, and the same method is used.

  Next, the CPU of the shape measurement processing PC 42 calculates the distance between the hand position and the object A based on the information of the shape measurement sensor 14, and brings the hand closer to the object A.

  Thereafter, the CPU of the shape measurement processing PC 42 analyzes the component of the object A by the component analyzer (S104).

  In the component analysis, first, the intensity of fluorescent X-rays emitted from the object A is measured by irradiating X-rays with a fluorescent X-ray analyzer mounted on the hand.

  Next, the CPU of the shape measurement processing PC 42 selects the constituent material of the object A by referring to the object information database 43b from the measured intensity spectrum value of the fluorescent X-ray, and further uses the material as a keyword for further object detection. The density of the object A is calculated by referring to the density information of the substance registered in the information database 43b (S105).

  Further, the CPU of the shape measurement processing PC 42 reads out the value of the friction coefficient of the object by referring to the object information database 43b for a general object constituted by the substance. In the present embodiment, the object A is assumed to be composed of a uniform material.

  Next, the CPU of the shape measurement processing PC 42 calculates the weight of the object A from the relational expression of weight = volume × density using the calculated volume and density information of the object (S106).

  Next, the CPU of the shape measurement processing PC 42 determines a suitable gripping force from the calculated weight of the object A and the friction coefficient value of the object obtained by referring to the object information database 43b (S107). The gripping force thus obtained is notified to the control PC 41 through the LAN 21.

  Next, the CPU of the control PC 41 notified of the gripping force confirms the position and orientation of the object A using the shape measurement sensor 14, and moves the tip end portion 12 a of the gripper unit 12 to a position where the object A can be gripped. Move (S108), close the tip 12a while grasping the object A while adjusting the grasping force with the measured value obtained from the grasping force measurement sensor (not shown) so as to obtain the previously determined grasping force. (S109).

  Finally, after lifting the object A, the accurate weight of the object A is measured by the 6-axis force sensor 15 attached to the gripper unit 12, and the measurement result is compared with the calculated weight. The gripping force corresponding to the error is adjusted (corrected) (S110).

  For example, if the actual weight is heavier than the calculated weight, the object A is prevented from sliding off from the finger portion of the gripper portion 12 by increasing the gripping force. On the other hand, it is also effective to mount a sliding tactile sensor on the finger and increase the gripping force when the sliding of the object A is detected.

  As described above, according to the first embodiment, since the shape of the object A is recognized and the weight is estimated (calculated) before the manipulator 11 holds the object A, the gripper 12 first uses the object A. The object A can be grasped with an appropriate grasping force from when the object A is grasped, and the change of the installation position of the object A can be autonomously handled, and the manipulator 11 can be grasped when the object A is grasped / moved. It is possible to eliminate errors such as the object A falling because the force is too weak or the gripping force of the manipulator 11 being too strong to crush (break) the object A.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIG. FIG. 3 is a flowchart showing the processing operation of the manipulator work support system of the second embodiment. In the following embodiments, the same configurations and operation steps as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  This second embodiment is an example of an operation of searching for a position where the gripper can be gripped and automatically setting it by measuring the shape of the object A in the configuration of the manipulator work support system shown in the first embodiment. is there.

  In the manipulator work support system according to the second embodiment, the CPU of the shape measurement processing PC 42 estimates the weight by the same process as in the first embodiment, that is, obtains the weight by calculation (S101 to S106), and then the object A The center-of-gravity position of the object A is obtained by calculation from the obtained three-dimensional shape data (S207).

  Next, the CPU of the shape measurement processing PC 42 specifies (determines) a position in the vicinity of the obtained gravity center position of the object A and that can be gripped by the gripper unit 12 (S208). The vicinity of the center of gravity refers to a range in which the distance from the center of gravity is set in advance.

  Although the grippable position depends on the finger shape of the gripper unit 12, for example, in the case of the gripper unit 12 including a simple two-finger opening / closing mechanism, it is determined from the opening width of the finger and the contact area of the gripping unit.

  If gripping is impossible at a position near the center of gravity, a grippable position is searched and determined as close to the center of gravity as possible.

  Next, the CPU of the shape measurement processing PC 42 determines a gripping force suitable for the object A from the weight of the object A obtained by calculation (S209). At this time, if the gripping position deviates from the center of gravity, the gripping force is determined using the value of the rotational moment generated by having the gripping position as one of the parameters, and the determined gripping force is notified to the control PC 41.

  The CPU of the control PC 41 that has received the notification of the gripping force operates the manipulator 11 while confirming the position and orientation of the object A based on the measurement values measured by the shape measurement sensor 14, and measures the shape of the gripper unit 12 (hand). It moves to the grippable position determined by the processing PC 42 (S210), and grips the object A by the gripper unit 12 at that position (S211).

  At this time, the CPU of the control PC 41 adjusts the gripping force of the gripper unit 12 so that the gripping force measurement value of a gripping force measurement sensor (not shown) becomes the previously determined force. Close the (hand) and hold the object A.

  Note that when the 6-axis force sensor 15 is used as a sensor for measuring the external force applied to the hand, not only the force component but also the moment component can be measured, so the center of gravity position of the object A is measured from the magnitude of the moment. It is possible to correct (correct) the position of the center of gravity obtained by calculation (S212).

  As described above, according to the second embodiment, in addition to the function of the first embodiment, it is possible to grip an object that can autonomously determine and correct the position of an object A whose grip position is uncertain.・ Movement work can be realized.

(Third embodiment)
Next, a third embodiment will be described with reference to FIG. FIG. 4 is a flowchart showing the processing operation of the manipulator work support system of the third embodiment.
In the third embodiment, the characteristic data of the object to be grasped is stored in the object information object information database 43b of the object information database PC 43 shown in the first embodiment.

  As shown in FIG. 4, object-specific information such as the accurate shape, weight, center of gravity position, grippable position, friction coefficient of gripping position, and appropriate gripping force of each target object is registered in the object information database 43b. Keep it.

  Next, during the gripping operation by the manipulator 11, the CPU of the shape measurement processing PC 42 measures the three-dimensional shape of the object A measured by the shape measurement sensor 14 of the grip unit 12 (hand) as in the first embodiment. Data is acquired (S302), and the density of the object A is calculated by referring to the object information database 43b based on the three-dimensional shape data (S303).

  Then, the CPU of the shape measurement processing PC 42 determines an appropriate gripping force by searching the object information database 43b and acquiring corresponding object-specific information, and the CPU of the control PC 41 determines the determined gripping force. Then, the manipulator 11 is operated to move the grip portion 12 (hand) to the position of the object A (S304), and the object A is gripped (S305).

  As an example of a search method using the three-dimensional shape measurement data of the object A, there is a method of performing comparison by comparing the positional relationship and size of the vertices representing the shape characteristics of the object A expressed in the three-dimensional space. .

  In this case, information unique to the object can be registered in the object information database 43b, so that not only information related to the gripping but also information on how to use the object A can be registered.

  For example, if the object A is a tool such as a screwdriver, information on how to use the tool, such as pressing the tip against a screw thread and rotating it in the longitudinal axis direction, is acquired from the object information database 43b and used for work. Can do.

  As described above, according to the third embodiment, the accurate shape, weight, center of gravity position, grippable position, friction coefficient of the gripping position, appropriate gripping force, etc. of the known gripping target are registered in the object information database 43b. By doing so, detailed information about the object A can be obtained, and an accurate gripping operation can be performed. In addition, the present invention can be applied not only to a gripping operation but also to work in a state where the object A is gripped.

(Fourth embodiment)
Next, a fourth embodiment will be described with reference to FIG. FIG. 5 is a flowchart showing the processing operation of the manipulator work support system of the fourth embodiment.

  In the third embodiment, information in the object information database 43b needs to be input and registered in advance by a human hand, and can only deal with a known object A.

  Therefore, in the fourth embodiment, data such as the shape and weight of the unknown object A acquired by the functions of the first embodiment and the second embodiment, an appropriate gripping force, and the like are registered in the object information database 43b. The object A that can be handled is automatically added.

  That is, in the manipulator work support system of the fourth embodiment, the CPU of the shape measurement processing PC 42 estimates the weight by the same processing as in the first embodiment (S101 to S106), and then obtains it from the object A. The center-of-gravity position of the object A is obtained by calculation from the three-dimensional shape data (S207).

  Next, the CPU of the shape measurement processing PC 42 specifies (determines) a position in the vicinity of the obtained gravity center position of the object A and that can be gripped by the gripper unit 12 (S208). The vicinity of the center of gravity means within a predetermined number of centimeters.

  Although the grippable position depends on the finger shape of the gripper unit 12, for example, in the case of the gripper unit 12 including a simple two-finger opening / closing mechanism, it is determined from the opening width of the finger and the contact area of the gripping unit.

  If gripping is impossible near the position of the center of gravity, the grippable position is searched and determined as close to the center of gravity as possible.

  Next, the CPU of the shape measurement processing PC 42 determines a gripping force suitable for the object A from the weight of the object A obtained by calculation (S209). At this time, if the gripping position deviates from the center of gravity, the gripping force is determined using the value of the rotational moment generated by having the gripping position as one of the parameters, and the determined gripping force is notified to the control PC 41.

  The CPU of the control PC 41 that has received the notification of the gripping force operates the manipulator 11 while confirming the position and orientation of the object A based on the measurement values measured by the shape measurement sensor 14, and measures the shape of the gripper unit 12 (hand). It moves to the grippable position determined by the processing PC 42 (S210), and grips the object A by the gripper unit 12 at that position (S211).

  At this time, the CPU of the control PC 41 adjusts the gripping force of the gripper unit 12 so that the gripping force measurement value of a gripping force measurement sensor (not shown) becomes the previously determined force. Close the (hand) and hold the object A.

  Note that when the 6-axis force sensor 15 is used as a sensor for measuring the external force applied to the hand, not only the force component but also the moment component can be measured, so the center of gravity position of the object A is measured from the magnitude of the moment. It is possible to correct (correct) the position of the center of gravity obtained by calculation (S212).

  Finally, the CPU of the shape measurement processing PC 42 registers the acquired data such as the shape and weight of the unknown object A, an appropriate gripping force, and the like in the object information database 43b, and updates the contents of the object information database 43b ( S413).

  As described above, according to the fourth embodiment, in addition to the information specific to the object A being known, the unknown information is measured and calculated, and the object information calculated is additionally registered in the object information database 43b. Thus, when gripping the same object again, the object can be gripped / moved with an appropriate gripping force even with respect to an object that is not manually registered in the database by referring to the object information database 43b.

(Fifth embodiment)
Next, a fifth embodiment will be described.
The fifth embodiment relates to the fourth embodiment, and approximates an object whose shape does not match the data of the object registered in the object information database 43b, that is, when the shape is similar, the similar object The characteristics of the object A are obtained by calculation based on the above data, and the manipulator 11 is controlled to hold the object A.

  For example, there are many similar tools of different sizes such as a screwdriver. Moreover, even if these tools differ in shape, the usage method as a tool is the same.

  As shown in the fourth embodiment, as a result of shape measurement, the object A does not match the shape existing in the object information database 43b, and the object A has an unknown shape, but the object information database 43b has a similar shape. If there is data, the CPU of the shape measurement processing PC 42 calculates the weight of the unknown object A from the information of the object having similar shape data, and estimates and determines the grip position, grip force, etc. At the same time, the usage method for the unknown object A is additionally registered in the object information database 43b as being the same as the known object.

  By calculating the characteristic data of the object A as shown in the first embodiment and the second embodiment, the characteristic estimation accuracy can be further improved.

  In addition, after actually carrying out the gripping work, the characteristic information of the object is added to the object information database 43b and registered so that it can be reused.

  As described above, according to the fifth embodiment, if object information having a shape similar to that in the object information database 43b exists even if the unique information of the object A is unknown, based on the object information. The characteristics of the object A can be obtained by calculation to determine parameters related to gripping, and it is possible to realize object gripping / moving work with improved estimation accuracy together with characteristic estimation based only on measurement.

(Sixth embodiment)
Next, a sixth embodiment according to the present invention will be described with reference to FIG. FIG. 6 is a diagram showing the configuration of the manipulator of the sixth embodiment.
In the sixth embodiment, in addition to the configuration shown in the first embodiment, the reader / writer 61 of the non-contact IC tag mounted on the hand portion (gripping portion 10) of the manipulator 11 and the reader / writer 61 write data. The information tag 60 as a non-contact IC tag is composed of a tag installation mechanism 62 for attaching the information tag 60 to the object A.

  The reader / writer 61 functions as an information writing unit that stores the characteristic data of the object A in the information tag 60.

  Further, the reader / writer 61 reads the characteristic data of the object A from the information tag 60 attached to the object A by wireless communication using light or radio waves and passes it to the shape measurement processing PC 42 which is a gripping force determination unit. It functions as a reading unit.

  An adhesive is applied to one side of the information tag 60. The tag installation mechanism 62 has a tubular portion 62a that can be expanded and contracted. The cylindrical portion 62a is an adsorption nozzle, and the other surface of the information tag 60 to which no adhesive is applied is adsorbed to the tip thereof by suction or the like.

  The tag installation mechanism 62 functions as an attachment portion for attaching the information tag 60 in which the characteristic data is written by the reader / writer 61 to the object A.

  In the case of this tag installation mechanism 62, the information tag 60 is affixed to the object A by pressing the information tag 60 against the object A and stopping the suction.

  In the method for searching and referring to the object information database 43b shown in the first to fifth embodiments, processing time is generated at the time of collation, and operation / management of the object information database 43b is required.

  Therefore, in the sixth embodiment, the reader / writer 61 writes characteristic data of the object once estimated to the information tag 60, and the tag setting mechanism 62 affixes the information tag 60 to the grasped object. The information tag 60 may be attached with a magnet or the like as well as being pasted.

  By doing so, the next time the same object A is gripped, the reader / writer 61 reads (reads) the characteristic data stored in the information tag 60 attached to the object A, and the shape measurement processing PC 42 is read. , The CPU of the shape measurement processing PC 42 can instantaneously determine parameters related to gripping such as an appropriate gripping position and gripping force of the object A without using measurement and calculation.

  As the information tag 60, in addition to an electrically readable / writable IC tag as in this example, a two-dimensional barcode may be printed and used on the spot. Since reading of the two-dimensional barcode is performed by a visual sensor, the shape measurement camera is mounted on the gripping unit 10. Further, instead of writing the characteristic data itself into the information tag 60, the address or path of the reference destination of the object information database 43b may be stored in the information tag 60.

  As described above, according to the sixth embodiment, the characteristic data relating to the grasping of the object A once estimated, that is, the parameters or the like are pasted on the object A to be written on the information tag 60, so that the next grasping operation can be performed. Without performing measurement, calculation, reference to the object information database 43b, and the like, it is possible to acquire the characteristics of the object instantaneously, hold the object A with an appropriate gripping force, and perform a moving operation.

(Seventh embodiment)
Next, a seventh embodiment will be described with reference to FIG. FIG. 7 is a diagram illustrating an example of a status display screen according to the seventh embodiment.
In the seventh embodiment, in the configuration shown in the first embodiment, the operator who operates the manipulator 11 confirms the state display displayed on the display 44a of the state display PC 44 and performs an operation, whereby the state of the manipulator 11 is Confirmation and instructions can be given.

  The CPU of the state display PC 44 displays the posture of the manipulator 11 itself, the position and posture of its hand, and the surrounding environmental structure on the display 44a by three-dimensional graphic processing so that it can be easily understood visually.

  On the status display screen 71 of the display 44a, the outer shape of the object A and the surrounding environmental structure are displayed realistically. When the operator moves the operation cursor 72 of the state display screen 71 with a mouse or the like and selects the display of the object A, the CPU of the state display PC 44 pops up the object information display window 73.

  In the object information display window 73, characteristic data such as material and weight of the object A registered in the object information database 43b and characteristic data such as material and weight of the object A measured by each measuring device are displayed. .

  Here, as the characteristic data to be displayed, the measurement results obtained by the component analysis device 13 and the shape measurement device 14 and the calculation results obtained by the shape measurement processing PC 42 shown in the first to third embodiments are used, and object information is displayed. The object information registered in the object information database 43b of the database PC 43 is read out by search and displayed.

  In addition, when the display of the object A on the status display screen 71 is selected by a mouse or the like, the CPU of the status display PC 44 transmits a trigger signal for starting gripping work to the control PC 41 via the LAN 21 and outputs the trigger signal. The received CPU of the control PC 41 may issue a control command for starting a gripping operation to the manipulator controller 30.

  As described above, according to the seventh embodiment, the operator can visually grasp the state of the robot and the characteristic data of the object A, and can select the object A displayed on the screen. Thus, since the characteristic data such as the material and weight of the object A is displayed, the operator can grasp and move the object while watching this.

  As described above, according to the above-described embodiment, the application range of the gripping operation of the manipulator 11 can be expanded. For example, the present invention can be applied to a robot that performs work in a space where various objects such as a home environment exist. It is possible to connect.

  In addition, this invention is not limited only to the said embodiment, A deformation | transformation is possible. In each of the above-described embodiments, the multi-axis and multi-joint manipulators 11 are used. However, the present invention is not limited to the above-described embodiment, and may be a single-axis (no joint) and grips an object. It can be widely applied to the mechanism.

  Moreover, although the example which mounts the measuring device which measures the material and shape of the target object A on the hand of the manipulator 11 was shown in the said embodiment, the mounting position of a measuring device is limited to the position of the hand of the manipulator 11. You may install in the position different from the part other than the hand of the manipulator 11, and the manipulator 11 instead of a thing.

  Furthermore, various embodiments described above can be combined as appropriate, and various modifications can be made without departing from the spirit of the present invention.

The figure which shows the structure of the manipulator control system of one Embodiment of this invention. The flowchart which shows the process of the manipulator control system of 1st Embodiment. The flowchart which shows the process of the manipulator control system of 2nd Embodiment. The flowchart which shows the process of the manipulator control system of 3rd Embodiment. The flowchart which shows the process of the manipulator control system of 4th Embodiment. The flowchart which shows the process of the manipulator control system of 6th Embodiment. The figure which shows the status display screen of the display in 7th Embodiment.

Explanation of symbols

A ... Object to be grasped 10 ... Gripping part 11 ... Manipulator 12 ... Gripper part 13 ... Component analyzer 14 ... Shape measuring device 15 ... 6-axis force sensor 17 ... Work table 18 ... Signal line / Power line 20 ... Communication line 21 ... LAN
30 ... Manipulator controller 41 ... Control computer (PC for control)
42 ... Computer for shape measurement processing (PC for shape measurement processing)
43 ... Object information database computer (object information database PC)
44 ... Status display computer (status display PC)
60 ... Information tag 61 ... Reader / writer 62 ... Tag installation mechanism 71 ... Status display screen 72 ... Operation cursor 73 ... Object information display window

Claims (10)

A manipulator having a gripping part for gripping and moving a gripping object;
A component analyzer that is provided in the gripping unit and that emits light or radiation to the gripping object that is approached to measure the material in a non-contact manner;
A shape measuring sensor that is provided in the grip portion and radiates light or radiation to the gripped object that is approached to measure the solid shape in a non-contact manner;
A volume calculation unit that calculates the volume of the gripping object from the material of the gripping object measured by the component analyzer and the three-dimensional shape measured by the shape measurement sensor;
A database that stores object information including the shape of a known object to be grasped, density information of a substance, grasping position, and grasping force;
The weight of the gripping object is calculated from the volume of the gripping object calculated by the volume calculation unit and the density information of the substance read from the database using the material of the gripping object measured by the component analyzer as a key. A weight calculating unit for calculating;
A gripping force calculator that calculates a gripping force of the gripping object from the weight of the gripping object calculated by the weight calculator;
And a control unit that operates the manipulator with the gripping force calculated by the gripping force calculation unit.   2. A means for obtaining a position in a three-dimensional space where a gripping part of the manipulator grips the gripping object based on the shape of the gripping object measured by the shape measuring sensor. The described manipulator control system. Using the measured shape of the gripping object as a search key, a search unit that searches for characteristic data of the gripping object from the object information database;
The manipulator control system according to claim 1, further comprising means for outputting characteristic data of the grasped object searched by the search unit.   As a result of the search by the search unit, if the information on the grasped object does not exist in the database, a registration unit is provided for additionally registering the measured and calculated information on the unknown object in the database. The manipulator control system according to claim 3. If the information of the gripping object does not exist in the database as a result of the search by the search unit, the data of the object similar to the shape of the gripping object is read from the database for the measured and calculated unknown object. And a data selection unit having the characteristic data as data of the gripping object,
A gripping force determining unit that determines an appropriate gripping position and a gripping force from among gripping positions and gripping forces stored in advance in the database on the basis of characteristic data of the gripping object. 3. The manipulator control system according to 3. An information writing unit for storing characteristic data of the gripping object in an information tag;
The manipulator control system according to any one of claims 1 to 5, further comprising an attachment unit that attaches the information tag written by the information writing unit to the grasped object.   6. An information reading unit that reads data of the gripping object from an information tag attached to the gripping object by wireless communication using light or radio waves and passes the data to the gripping force determination unit. The described manipulator control system. Display means for three-dimensionally displaying the positions and postures of the manipulator and the gripping object;
8. The apparatus according to claim 1, further comprising at least one of display means for displaying calculated values or estimated values of the shape, weight, and characteristics of the grasped object, or information read from the database. Manipulator control system. In a manipulator control method for gripping / moving the gripping object by controlling a manipulator having a gripping part for gripping / moving the gripping object,
A component analyzer provided in the gripping unit emits light or radiation to the gripping object that is approached, and measures the material in a non-contact manner;
A shape measuring sensor provided in the gripping unit radiates light or radiation to the gripping object that is approached, and measures the three-dimensional shape without contact;
A computer calculating a volume of the gripping object from a material of the gripping object measured by the component analyzer and a three-dimensional shape measured by the shape measurement sensor;
The computer calculates the weight of the gripping object from the calculated volume of the gripping object and the density information of the substance read from the database using the measured material of the gripping object as a key;
The computer calculates a gripping force for the manipulator to grip the gripping object from the calculated weight of the gripping object;
And a step of causing the computer to operate the manipulator with the calculated gripping force. In a program for a computer to control a manipulator having a gripping part for gripping and moving a gripping object,
The computer,
The component analyzer provided in the gripping part emits light or radiation to the gripping object and measured without contact, and the shape measurement sensor provided in the gripping part includes the gripping object. On the other hand, a volume calculation unit that calculates the volume of the grasped object from a three-dimensional shape that is measured in a non-contact manner by emitting light or radiation;
A database that stores object information including the shape of a known object to be grasped, density information of a substance, grasping position, and grasping force;
The weight of the gripping object based on the volume of the gripping object calculated by the volume calculation unit and the density information of the substance read from the database using the material of the gripping object measured by the component analyzer as a key. A weight calculation unit for calculating
A gripping force calculator that calculates a gripping force of the gripping object from the weight of the gripping object calculated by the weight calculator;
A program that functions as a control unit that operates the manipulator with the gripping force calculated by the gripping force calculation unit.

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