JP2014121788A - Robot and robot system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a robot capable of quickly and correctly positioning a treatment device at a target position and performing desired treatment.SOLUTION: A robot comprises: a gripping part 10 for gripping an object E; an arm 20 for relatively moving the object E and the gripping part 10; an inertia sensor 40 for detecting difference of inertia force acting on the gripping part 10 and inertia force acting on the object E; and a control device 60 for relatively moving the gripping part 10 toward the object E by controlling the arm 20, calculating deviation of a relative position between the gripping part 10 and the object E by using detection result of the inertia sensor 40 and adjusting the relative position between the gripping part 10 and the object E so as to compensate the deviation by controlling the arm 20 on the basis of calculation result.

Description

  The present invention relates to a robot having a movable part such as an arm mechanism.

  Conventionally, horizontal articulated robots (SCARA robots), orthogonal robots, and the like have been developed as industrial robots, and these robots are selected in accordance with applications that suit each feature. In these robots, a processing device having various functions is moved to a target position, and the processing device performs various types of processing on the object and processing for conveying the object.

  Usually, in such an industrial robot, it is required to move the processing device quickly and accurately in order to shorten the working time. For example, in the robot of Patent Document 1, a sensor is attached in front of the movement direction of the processing device, and highly accurate movement control is performed based on a future target value calculated based on output information from the sensor.

JP-A-9-267281

  However, the robot having such a movable part has a problem that the processing apparatus vibrates due to the movement of the movable part, and the deviation of the processing apparatus from the target position becomes large.

  For example, in a robot having an arm mechanism, high positional accuracy can be realized by using an actuator such as a motor and an angle sensor with high resolution called an encoder. However, since it is difficult to detect the vibration caused by the movement of the arm using only the angle sensor, it is difficult to perform an operation in which the positional accuracy is ensured unless sufficient time has passed until the vibration is stopped. Conventionally, the rigidity of the housing in which the robot is installed is increased so that vibration itself does not occur. However, such a method increases the size of the device and increases the cost. There's a problem.

  In addition, in order to detect a deviation of the processing apparatus with respect to the target position, a method using an optical detection unit has been studied. However, for example, in an imaging apparatus such as a camera as the detection means, the imaging rate becomes the limit of detection of positional deviation, and a rapid change in positional deviation due to vibration cannot be detected.

  Furthermore, a configuration in which a laser light source and an optical sensor are used as detection means and the position of the processing apparatus is detected with high accuracy by laser scanning is also conceivable. However, with such a configuration, the cost of the detection device becomes high, and a spatial restriction is imposed on the arrangement position of the laser light source so that the processing device does not enter the blind spot from the laser light source.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a robot capable of quickly and accurately positioning a processing device at a target position and performing a desired process. .

In order to solve the above problems, a robot according to the present invention includes a processing device that performs a predetermined process on an object, a moving device that relatively moves the object and the processing device, and inertia that acts on the processing device. A detection device that detects a difference between a force and an inertial force acting on the object, and the moving device is controlled to move the processing device relative to the object, and the detection result of the detection device is used to A relative position shift between the processing device and the object is calculated, and the moving device is controlled based on the calculation result, so that the shift is canceled out. And a control device for adjusting the relative position.
According to this configuration, since the generated vibration is detected as an inertial force by the detection device, it is possible to detect a vibration state such as a vibration direction and intensity with a simple configuration without using an expensive sensor. Further, unlike an optical imaging means, a change in vibration can be detected quickly and with high accuracy by using a normally known inertial force detection device. Then, by controlling so as to cancel out the deviation using the detection result by such a detection device, a robot that can quickly and accurately position the processing device at a target position and perform a desired processing can be obtained. It becomes possible.

In this invention, it has a support stand which supports the said object, and the said detection apparatus detects the inertial force which acts on the said processing apparatus, and the 2nd which detects the inertial force which acts on the said support base. Preferably, the control device calculates the deviation based on outputs of the first detection device and the second detection device.
According to this configuration, even if the support base that indicates the object vibrates due to the driving of the robot, it is possible to detect the vibration of the support base, and the relative relationship between the processing apparatus and the support base. The vibration amplitude can be calculated by detecting the vibration. By calculating the relative position shift between the processing device and the object using the value calculated in this way, the shift can be canceled with higher accuracy and the processing using the processing device can be performed with high position accuracy. Can do.

In the present invention, the moving device includes a first moving device that moves the processing device, and the control device moves the processing device by the first moving device so that the deviation is offset. desirable.
According to this configuration, it is possible to cancel the positional deviation of the processing apparatus while leaving the object stationary.

In this invention, the said moving apparatus contains the 2nd moving apparatus which moves the support stand which supports the said target object, The said control apparatus is the said support stand by the said 2nd move apparatus so that the said shift | offset | offset may be offset. It is good also as moving.
According to this configuration, it is possible to cancel the positional deviation of the processing apparatus by moving the object together with the support base. Furthermore, when the shift is canceled by moving both the processing apparatus and the object, the movement amounts of the processing apparatus and the support base are small, and the shift can be quickly canceled.

In this invention, it has the 1st support stand and 2nd support stand which support the said target object, The said detection apparatus detects the inertial force which acts on the said processing apparatus, The said 1st support A second detection device for detecting an inertial force acting on the table; and a third detection device for detecting an inertial force acting on the second support table; and a position detection means for detecting the position of the processing device, The control device detects the difference based on outputs of the first detection device and the second detection device when the first detection device is on the first support base, and the first detection device When it is on the second support, it is desirable to detect the difference based on the outputs of the first detection device and the third detection device.
According to this configuration, a detection device to be used for detecting a positional shift of the relative position between the processing device and the object is appropriately selected according to the position of the processing device, and the position between the processing device and the object is surely determined. The deviation can be detected and canceled.

In the present invention, the moving device includes a second moving device that moves the first support base and a third moving device that moves the second support stand, and the control device includes the first detection device. When the apparatus is on the first support base, the first support base is moved by the second moving device so that the deviation is offset, and when the first detection device is on the second support base It is desirable that the second support base is moved by the third moving device so that the deviation is offset.
According to this configuration, it is possible to cancel the positional deviation of the processing apparatus by moving the object. Furthermore, when the shift is canceled by moving both the processing device and the object, the movement amount of each of the processing device and the first and second support bases is small, and the shift can be canceled quickly. It becomes.

1 is a schematic configuration diagram illustrating a robot according to a first embodiment of the present invention. It is explanatory drawing which shows the robot of 1st Embodiment of this invention. It is a schematic block diagram which shows the robot of 2nd Embodiment of this invention. It is a top view which shows the robot of 2nd Embodiment of this invention.

[First Embodiment]
The robot according to the first embodiment of the present invention will be described below with reference to FIGS. In all the drawings below, the dimensions and ratios of the constituent elements are appropriately changed in order to make the drawings easy to see.

  In the following description, an xyz orthogonal coordinate system is set, and the positional relationship of each member will be described with reference to this xyz orthogonal coordinate system. Here, the predetermined direction in the horizontal plane is the x-axis direction, the direction orthogonal to the x-axis direction in the horizontal plane is the y-axis direction, and the direction orthogonal to each of the x-axis direction and the y-axis direction (that is, the vertical direction) is the z-axis direction. And

  FIG. 1 is a schematic configuration diagram illustrating a robot according to the present embodiment. As shown in the figure, the robot 1 of the present embodiment includes a gripping unit (processing device) 10 that grips an object E, an arm (moving device, first moving device) 20 that has the gripping unit 10 at the tip, and a target. The support 30 on which the object E is placed, the inertial sensor (detection device) 40 provided on the grip 10 and the support 30, the base 50 that supports the arm 20 and the support 30, and the operation of the robot 1 itself And a control device 60 that controls the control device 60 and an input device 70 that gives an input instruction to the control device 60.

  The arm 20 includes a first arm 21, a second arm 22, and a third arm 23 connected in this order. The first arm 21 has a columnar main shaft 24 having a rotation axis in the z-axis direction and a substantially rectangular shape in plan view. The base 50 is connected to the base 50. The first arm 21 rotates in the forward and reverse directions around the rotation axes L1 and L2 in the horizontal direction (in the xy plane) at the connection point with the main shaft 24 and the second arm 22 at the connection point with the first arm 21, respectively. It is provided as possible. The third arm 23 is provided so as to be able to rotate forward and backward around the rotation axis L3 in the horizontal direction and to be vertically driven in the vertical direction (z-axis direction) at the connection point with the second arm 22.

  The support base 30 includes a top plate 31 on which the object E is placed, and a base portion (moving device, second moving device) 35 that supports the top plate 31. For example, the base unit 35 includes a moving mechanism that horizontally moves the top plate 31 in the x direction and a moving mechanism that horizontally moves the top plate 31 in the y direction. It is provided so as to be movable within.

  The inertial sensor 40 includes a first inertial sensor (first detection device) 41 provided on the grip 10 and a second inertial sensor (second detection device) 42 provided on the top plate 31. Each of the inertial sensors 41 and 42 detects the vibration of the grip portion 10 and the top plate 31 by detecting the inertial force generated by the vibration. As the inertial sensor 40, for example, an acceleration sensor or an angular velocity sensor such as a gyro sensor can be used.

  The control device 60 includes a memory, a CPU, a power supply circuit, and the like. The control device 60 stores an operation program that defines the operation content of the robot 1 input from the input device 70, and activates various programs stored in the memory by the CPU to control the robot 1 in an integrated manner.

  Here, when the robot 1 performs an operation of holding and moving the object E, the arm 20 may vibrate due to the movement of the holding unit 10 or the arm 20. It is also conceivable that the vibration of the arm 20 is transmitted to the support base 30 via the base 50 and the support base 30 vibrates.

  For example, when the entire arm 20 vibrates in the horizontal direction due to the horizontal movement of the arm 20, the coordinates P <b> 1 on the xy plane of the object E indicated by a two-dot chain line extending in the z direction in the figure, and the gripping unit 10. There is a possibility that the object E cannot be accurately grasped due to a deviation from the coordinate P2 on the xy plane. That is, there is a possibility that a positional deviation occurs between the coordinates P1 of the object E, which is the target position, and the coordinates P2 of the grip 10.

  In the robot 1 according to the present embodiment, the vibration state of the grip unit 10 and the top plate 31 is detected by the inertial sensor 40, and the driving conditions for the arm 20 and the base unit 35 are detected based on the detection result. By calculating the driving condition, the driving condition is set so as to cancel out the deviation due to the vibration.

  FIG. 2 is an explanatory diagram showing the robot 1 and is a schematic sectional view in the xz plane. As shown in the figure, an actuator 211 for rotating the first arm 21 forward and backward around the rotation axis L1 inside the main shaft 24 and connecting the main shaft 24 and the first arm 21, And an angle sensor 212 that detects a rotation angle from the reference position.

  In addition, an actuator 221 that rotates the second arm 22 forward and backward around the rotation axis L <b> 2 around the rotation axis L <b> 2 inside the first arm 21 and at a connection portion between the first arm 21 and the second arm 22, And an angle sensor 222 that detects a rotation angle from the reference position.

  Similarly, an actuator 231 that rotates the third arm 23 forward / reversely around the rotation axis L3 or moves up and down at the connection point between the second arm 22 and the third arm 23 inside the second arm 22; And a position sensor 232 for detecting the rotation angle of the third arm 23 from the reference position and the position of the grip 10 in the vertical direction (z direction).

  The control device 60 includes a vibration detection unit 61 that detects a relative value of acceleration between the grip unit 10 and the top plate 31, a vibration amount calculation unit 62 that calculates a relative vibration amount of the grip unit 10 with respect to the top plate 31, A vibration correction unit 63 that calculates the amount of deviation of the gripping unit 10 from the target position and a drive signal generation unit 64 that generates a drive signal to be transmitted to each actuator in order to cancel the deviation are included.

  The vibration detection unit 61 acquires the detection results of the first inertia sensor 41 and the second inertia sensor 42, and calculates the relative value of the detection results of both sensors. That is, a relative value between the acceleration applied to the gripping unit 10 and the acceleration applied to the top plate 31 is detected.

  The vibration amount calculation unit 62 calculates the relative vibration amount between the grip 10 and the top plate 31 using the relative value obtained by the vibration detection unit 61 and the transfer function stored in the memory 65.

  The vibration correcting unit 63 obtains the current position (coordinates) of the gripping unit 10 using the vibration amount of the gripping unit 10, the detection results of the angle sensors and position sensors of the arm 20, and the dimensions of the arm 20, and grips the gripping unit 10. The amount of deviation from the target position (for example, the position of the object E) where the unit 10 should be located is calculated.

  The drive signal generation unit 64 uses, as a drive signal, a torque command value to be transmitted to each actuator in order to cancel the shift, using the deviation amount obtained by the vibration correction unit 63 and the transfer function stored in the memory 66. Generate. Each actuator included in the arm 20 receives the torque command value and is driven so as to cancel the positional deviation due to vibration, thereby arranging the gripping portion 10 at the target position and realizing accurate gripping.

  Further, in addition to the arm 20, the base portion 35 of the support base 30 may be driven to cancel the positional deviation. The correction of the position shift by the arm 20 and the support base 30 may be performed by only one of them, or both may be performed in cooperation. When the arm 20 and the support base 30 are driven to cooperate so as to cancel the displacement due to vibration, the amount of each drive is small, and therefore it is easy to correct the displacement.

  According to the robot 1 configured as described above, the displacement caused by the vibration is canceled using the detection result of the inertial sensor 40, and the processing (gripping) is performed by quickly and accurately positioning the grip portion 10 at the target position. It becomes possible to make it.

  Although the robot 1 of the present embodiment is provided with the second inertia sensor 42 on the top plate 31, the robot 1 may include only the first inertia sensor 41 that detects the vibration of the grip portion 10. Even with such a configuration, the gripping unit 10 can accurately grip the arm 20 by driving the arm 20 so as to cancel the vibration generated in the gripping unit 10.

[Second Embodiment]
3 and 4 are explanatory diagrams of the robot 2 according to the second embodiment of the present invention. The robot 2 of the present embodiment is partially in common with the robot 1 of the first embodiment. The difference is that a plurality of (two in the figure) support bases on which the object E is placed are provided, and each support base is provided with an inertial sensor. Therefore, in this embodiment, the same code | symbol is attached | subjected about the component which is common in 1st Embodiment, and detailed description is abbreviate | omitted.

  FIG. 3 is a schematic configuration diagram illustrating the robot 2 according to the second embodiment. As shown in the figure, the robot 2 includes a first support base 30A and a second support base 30B, and includes a top plate 31A, a base portion (moving device, second moving device) 35A, and a top plate 31B, respectively. A base unit (moving device, third moving device) 35B. Each base portion 35A, 35B is provided with a moving mechanism that allows the top plates 31A, 31B to be driven in the xy plane.

  The inertial sensor 40 includes a first inertial sensor 41 provided on the gripper 10, a second inertial sensor 42 provided on the top plate 31A, and a third inertial sensor (third detection device) provided on the top plate 31B. 43. The second inertia sensor 42 detects the vibration of the top plate 31A by detecting the inertia force generated by the vibration, and the third inertia sensor 43 detects the vibration of the top plate 31B by detecting the inertia force generated by the vibration. Is detected.

  The control device 60 receives the detection results of the inertial sensors 41, 42, and 43, and controls the operation of the arm 20 and the base portions 35A and 35B so as to cancel the detected vibrations. The control device 60 selects which one of the signals from the inertial sensors 42 and 43 is adopted depending on which of the first support base 30A and the second support base 30B the gripper 10 performs work on. doing.

  FIG. 4 is a plan view of the robot 2 of the present embodiment. As shown in FIG. 4A, when the gripper 10 performs work on the first support base 30A, in other words, when the target position where the gripper 10 should be located is on the first support base 30A. Uses the detection results of the first inertial sensor 41 and the second inertial sensor 42 to calculate the relative value between the acceleration of the gripping part 10 and the acceleration of the top plate of the first support base 30A to obtain the amount of deviation.

  On the other hand, as shown in FIG. 4B, when the gripper 10 performs work on the second support base 30B, in other words, the target position where the gripper 10 should be positioned is on the second support base 30B. In some cases, the detection result of the first inertia sensor 41 and the third inertia sensor 43 is used to calculate the relative value between the acceleration of the grip portion 10 and the acceleration of the top plate of the first support base 30B, and the amount of deviation. Ask for.

  As to which of the detection results of the second inertia sensor 42 and the third inertia sensor 43 is adopted, for example, the detection result of the angle sensor (position detection means) built in the arm 20 and each of the arms 20 The current position of the gripping unit 10 can be calculated from the length of the configuration, and the detection result of the corresponding inertial sensor can be adopted.

  In addition, based on the information on the trajectory that the gripping part 10 should pass, the position of the gripping part 10 is grasped, and which of the first support base 30A and the second support base 30B is on the support base is determined. It is good also as employ | adopting the detection result of a corresponding inertial sensor by detecting. For example, when the determined movement of the arm 20 is repeated at a determined speed, the current position of the gripper 10 can be calculated and calculated in the control device 60 by measuring the time from the start of the work. . Thus, when detecting the position of the gripping part 10 based on the set value, the control device 60 that performs the position detection calculation corresponds to the position detection means of the present invention.

  The arm 20 and either one or both of the base portions 35A and 35B of the first and second support bases 30A and 30B are driven in cooperation so as to cancel out the deviation amount thus obtained. Thus, gripping with high positional accuracy by the gripping unit 10 is realized.

  In the robot 2 configured as described above, since the displacement of the gripping part 10 is detected using the inertial sensor of the support base where the target position is set, the gripping part 10 is quickly and accurately positioned at the target position. It is possible to perform desired processing.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the above-described embodiment, the robot including the grip unit 10 is described as the processing device. However, the present invention is not limited to this, and other configurations that perform processing on an object may be employed. For example, examples of the processing apparatus include a nozzle that applies a liquid material to an object, an irradiation apparatus that irradiates laser light, and the like.

  Further, when the processing apparatus performs continuous processing such as applying and drawing a liquid material on a substrate placed on a support table, the vibration is always detected while the processing is being performed. It is better to offset the deviation. In such a process, the vibration amount can also be obtained based on the deviation between the target locus determined by temporal change of the target position and the locus of the processing device. In the case of such continuous processing, a timing at which the acceleration applied to the processing device changes, such as a location where the trajectory of the processing device bends, according to the programmed movement of the processing device is provided in advance as a set value. A process for distinguishing between an acceleration change and an acceleration change due to vibration may be added.

  In the above-described embodiment, the configuration is such that the generated vibration is canceled when the processing device is moved by the SCARA robot. However, the present invention is not limited to this, and when the processing device is moved by another type of robot such as an orthogonal robot. It is also possible to cancel the vibration.

  In the above-described embodiment, the arm (moving device) is mounted on the base. However, a bridge that straddles the support is attached to the base, and the arm is suspended from the bridge. Is also possible.

  DESCRIPTION OF SYMBOLS 1, 2 ... Robot, 10 ... Grasping part (processing apparatus), 20 ... Arm (1st moving apparatus, moving apparatus), 30 ... Support stand, 30A ... 1st support stand (support stand), 30B ... 2nd support stand (Support base), 35, 35A ... base portion (second moving device, moving device), 35B ... base portion (third moving device, moving device), 40 ... inertial sensor (detecting device), 41 ... first inertial sensor (First detection device), 42 ... second inertial sensor (second detection device), 43 ... third inertial sensor (third detection device), 60 ... control device, E ... object,

The present invention relates to a robot having a movable part such as an arm mechanism and a robot system .

Claims (6)

A processing device for performing predetermined processing on an object;
A moving device for relatively moving the object and the processing device;
A detection device for detecting a difference between an inertial force acting on the processing device and an inertial force acting on the object;
Controlling the moving device and relatively moving the processing device toward the object, and calculating a relative position shift between the processing device and the object using a detection result of the detection device, A robot comprising: a control device that controls the moving device based on a calculation result and adjusts a relative position between the processing device and the object so that the deviation is offset. A support base for supporting the object;
The detection device includes a first detection device that detects an inertial force that acts on the processing device, and a second detection device that detects an inertial force that acts on the support base,
The robot according to claim 1, wherein the control device calculates the deviation based on outputs of the first detection device and the second detection device. The moving device includes a first moving device that moves the processing device,
The robot according to claim 1, wherein the control device moves the processing device by the first moving device so that the deviation is offset. The moving device includes a second moving device that moves a support that supports the object,
4. The robot according to claim 1, wherein the control device moves the support base by the second moving device so that the deviation is canceled out. 5. A first support base and a second support base for supporting the object;
The detection device detects a first detection device that detects an inertial force acting on the processing device, a second detection device that detects an inertial force acting on the first support base, and an inertial force that acts on the second support stand. A third detecting device,
Having position detecting means for detecting the position of the processing device;
The control device detects the difference based on outputs of the first detection device and the second detection device when the first detection device is on the first support base, and the first detection device 4. The robot according to claim 1, wherein the difference is detected based on outputs of the first detection device and the third detection device when the robot is on the second support base. 5. The moving device includes a second moving device that moves the first support base, and a third moving device that moves the second support base,
When the first detection device is on the first support base, the control device moves the first support base by the second moving device so that the deviation is canceled, and the first detection device The robot according to claim 5, wherein the second support base is moved by the third moving device so that the deviation is canceled when the second support base is on the second support base.

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