Control method, control system and program
By combining tactile and force sensors to calculate contact force, the method addresses accuracy issues in existing gripping force determination, ensuring precise and safe object handling in diverse environments.
Patent Information
- Application Number
- JP2023073719
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2018-03-27
- Filing Date
- 2023-04-27
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2039-01-22
AI Technical Summary
Existing techniques for calculating contact force between a robot hand and an object using pressure detection elements have accuracy issues, leading to challenges in accurately determining the gripping force, especially in unpredictable environments where object properties are unknown.
A control method that utilizes both tactile sensors and force sensors to calculate contact force by integrating their sensing results, allowing for precise determination of contact force and slip detection at multiple contact points.
Enhances the accuracy of contact force calculation and slip detection, enabling safer and more precise gripping of objects with varying properties, even in complex environments.
Smart Images

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Abstract
Description
[Technical field]
[0001] The present disclosure relates to a control method , control system and program Regarding. [Background technology]
[0002] Conventionally, various machines having a structure for gripping an object (for example, a robot hand or a gripper) have been proposed.
[0003] For example, Patent Document 1 listed below describes a technique for detecting contact with an object using a plurality of pressure detection elements arranged at predetermined joints of a robot hand. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] JP 2009-66714 A Summary of the Invention [Problem to be solved by the invention]
[0005] However, in the technology described in Patent Document 1, the contact force when the robot hand comes into contact with an object is calculated using only the sensing result by the pressure detection element. Therefore, in the technology described in Patent Document 1, there is room for improvement in the accuracy of the calculation of the contact force.
[0006] Therefore, the present disclosure proposes a technique that can appropriately control the gripping force when the contact portion comes into contact with an object. [Means for solving the problem]
[0007] According to the present disclosure, a control device is provided that includes a gripping control unit that controls a gripping force associated with the contact portion in accordance with a contact force when the contact portion comes into contact with an object, based on the sensing result of a tactile sensor arranged in the contact portion and the sensing result of a force sensor arranged in the contact portion.
[0008] Furthermore, according to the present disclosure, a control method is provided that includes a processor controlling a gripping force associated with the contact portion in response to a contact force when the contact portion comes into contact with an object, the contact force being based on a sensing result by a tactile sensor arranged in the contact portion and a sensing result by a force sensor arranged in the contact portion.
[0009] In addition, according to the present disclosure, a program is provided for causing a computer to function as a gripping control unit that controls the gripping force associated with the contact portion in accordance with the contact force when the contact portion comes into contact with an object, based on the sensing results of a tactile sensor arranged in the contact portion and the sensing results of a force sensor arranged in the contact portion. Effect of the Invention
[0010] According to the present disclosure, it is possible to appropriately control the gripping force when the contact portion comes into contact with an object. Note that the effects described herein are not necessarily limited to those described herein, and may be any of the effects described in the present disclosure. [Brief description of the drawings]
[0011] [Figure 1] 1 is a diagram illustrating an example of a physical configuration of a robot 10 according to a first embodiment of the present disclosure. [Diagram 2] 1 is a block diagram showing an example of a functional configuration of a robot 10 according to a first embodiment. [Diagram 3] 2 is a block diagram showing an example of a detailed configuration of a contact force identification unit 110 according to the first embodiment. FIG. [Figure 4] 4 is a flowchart showing an example of a process flow according to the first embodiment. [Diagram 5] FIG. 11 is a block diagram showing an example of a functional configuration of a robot 10 according to a second embodiment of the present disclosure. [Figure 6] FIG. 11 is a block diagram showing an example of a functional configuration of a robot 10 according to a third embodiment of the present disclosure. [Figure 7] FIG. 11 is a block diagram showing an example of a functional configuration of a robot 10 according to a fourth embodiment of the present disclosure. [Figure 8] FIG. 13 is a block diagram showing an example of a functional configuration of a robot 10 according to a fifth embodiment of the present disclosure. [Figure 9] FIG. 13 is a block diagram showing an example of a functional configuration of a robot 10 according to a sixth embodiment of the present disclosure. [Figure 10] FIG. 13 is a block diagram showing an example of a functional configuration of a robot 10 according to a seventh embodiment of the present disclosure. [Figure 11] FIG. 13 is a block diagram showing an example of a functional configuration of a robot 10 according to an eighth embodiment of the present disclosure. [Figure 12] FIG. 13 is a block diagram showing an example of a functional configuration of a robot 10 according to a ninth embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same functional configurations are denoted by the same reference numerals, and redundant description will be omitted.
[0013] In addition, in this specification and drawings, multiple components having substantially the same functional configuration may be distinguished by adding different alphabets after the same reference numeral. For example, multiple components having substantially the same functional configuration may be distinguished as gripping portion 104a and gripping portion 104b as necessary. However, when there is no need to particularly distinguish between multiple components having substantially the same functional configuration, only the same reference numeral is used. For example, when there is no need to particularly distinguish between gripping portion 104a and gripping portion 104b, they are simply referred to as gripping portion 104.
[0014] The "Mode for Carrying Out the Invention" will be described in the following item order. 1. Background 2. First embodiment 3. Second embodiment 4. Third embodiment 5. Fourth embodiment 6. Fifth embodiment 7. Sixth embodiment 8. Seventh embodiment 9. Eighth embodiment 10. Ninth embodiment 11. Variations
[0015] <<1.Background>> The present disclosure may be embodied in various forms, as will be described in detail in "2. First embodiment" to "10. Ninth embodiment" as examples. First, in order to clearly show the features of the present disclosure, the background to the creation of the robot 10 according to each embodiment of the present disclosure will be described.
[0016] Conventionally, various techniques have been proposed for gripping an object using a hand unit (e.g., a robot hand or a gripper). In such techniques, the gripping force with which the hand unit grips an object must be set appropriately. For example, the gripping force must be set within a range that does not cause the object to slip off and does not crush the object.
[0017] In addition, since the shape, mass, and friction coefficient of objects handled on a factory assembly line are often known, it is usually easy to set an appropriate gripping force for the object. On the other hand, for a wide variety of objects located in an arbitrary environment such as a home or hospital, the shape, mass, or friction coefficient of each object is often unknown, making it difficult to set an appropriate gripping force.
[0018] To solve this problem, a technology has been proposed in which, for example, a pressure distribution sensor is placed at the tip (fingertip) of the hand unit, the CoP (Center Of Pressure) is measured, which changes when there is a relative misalignment (hereinafter referred to as "slippage") between the object to be grasped and the fingertip, and the grasping force is increased based on the measurement results.
[0019] However, due to the characteristics of the pressure distribution sensor, there are limitations on the contact state, sensor accuracy, spatial resolution, dynamic range, etc., so this technology has low accuracy in calculating the contact force. And because the accuracy of calculating the contact force is low, this technology also has difficulty in accurately detecting slippage.
[0020] Therefore, with the above circumstances as a primary focus, the robot 10 according to each embodiment has been created. The robot 10 according to each embodiment calculates the contact force when the gripper 104 comes into contact with an object, based on the sensing result by the tactile sensor 106 arranged in the gripper 104 and the sensing result by the force sensor 108 arranged in the gripper 104. As described above, according to each embodiment, since both the sensing result by the tactile sensor 106 and the sensing result by the force sensor 108 are used, the contact force when the gripper 104 comes into contact with an object can be calculated with higher accuracy.
[0021] The robot 10 according to each embodiment is an example of a control device according to the present disclosure. In each embodiment, the robot 10 may be a device (machine) capable of performing an action (e.g., grasping) using electrical and / or magnetic action. For example, the robot 10 may be a mobile or fixed manipulation device. Alternatively, the robot 10 may be a humanoid robot, a pet robot, various industrial machines, a vehicle (e.g., an autonomous vehicle, a ship, or an aircraft (e.g., a drone)), or a toy. The contents of each embodiment will be described in detail below.
[0022] <<2. First embodiment>> <2-1.Physical configuration> Next, a first embodiment according to the present disclosure will be described. First, the physical configuration of a robot 10 according to the first embodiment will be described with reference to FIG.
[0023] 1, the robot 10 may have at least one gripper 104 and an actuator 130 that drives the gripper 104. Also, as shown in FIG 1, a tactile sensor 106 may be disposed on the entire or part of the surface of the gripper 104. Furthermore, a force sensor 108 may be disposed, for example, within the area where the actuator 130 is disposed.
[0024] {2-1-1.Gripping part 104} The gripping unit 104 is an example of a contact unit according to the present disclosure. The gripping unit 104 has a structure capable of gripping an external object (object 20 in the example shown in FIG. 1). In the example shown in FIG. 1, the gripping unit 104 is a robot finger, but the first embodiment is not limited to such an example. As long as the gripping unit 104 has a structure capable of gripping an object, the structure is not particularly limited. For example, the robot 10 may have one or more robot arms (not shown). In this case, the gripping unit 104 may be disposed at the tip of the robot arm as a hand unit (e.g., a robot hand, a gripper, or an end effector). Alternatively, the robot 10 may have a plurality of legs. In this case, the gripping unit 104 may be disposed as the tip (e.g., a foot) of one of the plurality of legs.
[0025] {2-1-2. Tactile Sensor 106} The tactile sensor 106 may be configured to be capable of measuring the contact position with an object (e.g., the contact center position, etc.) and the total number of individual contact points (hereinafter, also referred to as contact locations) when in contact with the object. For example, the tactile sensor 106 may be a pressure distribution sensor, a one-axis force sensor array, a three-axis force sensor array, a vision sensor, or a sensor using a laser. Here, the pressure distribution sensor may be a sensor in which a plurality of pressure detection elements are arranged in an array. The pressure distribution sensor may sense contact with an object by detecting pressure applied to each of the plurality of pressure detection elements. The vision sensor may sense contact with an object by measuring, with a camera, the deformation of the material of the sensor surface caused by contact with the object. The laser-based sensor may sense the presence or absence of contact between the sensor surface and the object by using a laser.
[0026] The tactile sensor 106 may further be capable of measuring a contact force intensity ratio between each contact point, where the contact force may be a force generated at a point of contact with an object, or may further be capable of measuring a normal force at each contact point and / or an absolute value of a shear force at each contact point.
[0027] Furthermore, the tactile sensor 106 can transmit the sensing results (eg, the total number of contact points, position information of each contact point, and the contact force intensity ratio between each contact point) to the contact force identification unit 110 and the slippage detection unit 112.
[0028] {2-1-3. Force sensor 108} The force sensor 108 may be configured to measure a resultant force of a contact force (in other words, a reaction force from an object) applied to the surface of the gripping unit 104 when an object comes into contact with the gripping unit 104. Alternatively, the force sensor 108 may be configured to measure a force, torque, or moment generated by the actuator 130.
[0029] For example, the force sensor 108 may be a three-axis force sensor or a six-axis force sensor. Alternatively, a torque sensor may be disposed in the actuator 130, and the force sensor 108 may be the torque sensor. In this case, the force sensor 108 may measure the torque generated by the actuator 130 (as the force generated by the actuator 130).
[0030] Furthermore, the force sensor 108 can transmit the sensing result (force, torque, or moment) to the contact force determination unit 110 and the grip control unit 100.
[0031] {2-1-4. Actuator 130} The actuator 130 can generate a force (or torque) corresponding to a target command value according to the control of the grip control unit 100 described below. The generated force is transmitted to the grip unit 104, causing the grip unit 104 to operate. For example, the actuator 130 is driven according to the control of the grip control unit 100 so that the grip unit 104 can generate a target gripping force (in other words, a force, moment, or torque that the actuator 130 should generate).
[0032] 1, the actuator 130 may be disposed between the gripper 104 and a main body (not shown) of the robot 10. For example, in the case where the robot 10 has a robot arm connected to the gripper 104, the actuator 130 may be disposed within the robot arm.
[0033] <2-2. Functional configuration> The physical configuration of the robot 10 according to the first embodiment has been described above. Next, the functional configuration of the robot 10 according to the first embodiment will be described with reference to FIG. 2. FIG. 2 is a block diagram showing an example of the functional configuration of the robot 10 according to the first embodiment. As shown in FIG. 2, the robot 10 has a grip control unit 100, a grip unit 104, a tactile sensor 106, a force sensor 108, a contact force identification unit 110, and a slippage detection unit 112. In the following, descriptions that overlap with the above description will be omitted.
[0034] {2-2-1. Contact force identification section 110} The contact force identification unit 110 is an example of a contact force calculation unit according to the present disclosure. The contact force identification unit 110 may include a processing circuit such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). Furthermore, the contact force identification unit 110 may include a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory).
[0035] The contact force specifying unit 110 calculates the contact force when the grip unit 104 comes into contact with an object, based on the sensing result by the tactile sensor 106 and the sensing result by the force sensor 108. For example, when the grip unit 104 comes into contact with an object at one or more points, the contact force specifying unit 110 calculates the contact force at each of the contact points, based on information about each of the contact points identified from the sensing result by the tactile sensor 106 and the sensing result by the force sensor 108. As will be described later, the information about each of the contact points includes, for example, the total number of contact points, position information about each of the contact points, and a contact intensity ratio between each of the contact points.
[0036] Here, a more detailed configuration of the contact force identification unit 110 will be described with reference to Fig. 3. Fig. 3 is a block diagram showing an example of a more detailed configuration of the contact force identification unit 110. As shown in Fig. 3, the contact force identification unit 110 can have a contact point number calculation unit 150, a contact position calculation unit 152, a contact strength calculation unit 154, and a contact force calculation unit 156.
[0037] {2-2-2. Contact point number calculation unit 150} When it is detected that the gripper 104 and the object are in contact at one or more points, the contact point number calculation unit 150 calculates the total number of contact points (contact locations) based on the sensing results of the tactile sensor 106. At this time, for example, the contact point number calculation unit 150 calculates the total number of contact points based on a calculation method corresponding to the type of the tactile sensor 106 and the sensing results of the tactile sensor 106.
[0038] As an example, when the tactile sensor 106 is configured to include a pressure distribution sensor, the contact point number calculation unit 150 first identifies (calculates) the number of maximum points of pressure sensed by the tactile sensor 106, or identifies individual points where the gradient of the pressure distribution approaches "0." Then, the contact point number calculation unit 150 calculates the total number of contact points based on these identification results.
[0039] Alternatively, when tactile sensor 106 is configured to include a vision sensor, contact point number calculation unit 150 first identifies a change in the amount of deformation of the surface of tactile sensor 106 resulting from contact between gripper 104 and an object, based on the sensing result by tactile sensor 106. Then, contact point number calculation unit 150 calculates the total number of contact points based on this identification result.
[0040] {2-2-3. Contact position calculation unit 152} The contact position calculation unit 152 specifies the positional relationship of each of all the corresponding contact points (hereinafter, may be referred to as "each contact point") based on the sensing result by the tactile sensor 106. For example, the contact position calculation unit 152 specifies the position information of each contact point (for example, the position information of the center position of each contact point, etc.) based on the sensing result by the tactile sensor 106. As an example, the contact position calculation unit 152 specifies, for each contact point, information on the relative position of the contact point on the tactile sensor 106 as the position information of the contact point based on the sensing result by the tactile sensor 106. Here, the information on the relative position of each contact point may be expressed in the form of coordinates with the end point of the tactile sensor 106 as the origin. However, without being limited to such an example, the information on the relative position of each contact point may be defined as information on the relative position based on any other position at which the torque or moment generated by the actuator 130 can be calculated.
[0041] {2-2-4. Contact strength calculation unit 154} The contact strength calculation unit 154 calculates the contact force strength ratio between the corresponding contact points (for example, the contact strength ratio of each of the other contact points based on the contact strength of a certain contact point) based on the sensing result by the tactile sensor 106. The advantages of such a calculation method include the following. For example, when a predetermined sensing result contains an error that is overall multiplied by a certain coefficient of gain (for example, temperature determination, etc.), the gain can be offset by using the contact force strength ratio between the respective contact points, so that the effect of the error can be minimized.
[0042] {2-2-5. Contact force calculation section 156} The contact force calculation unit 156 calculates the contact force at each contact point based on the total number of contact points calculated by the contact point number calculation unit 150, the position information of each contact point specified by the contact position calculation unit 152, the contact force intensity ratio between each contact point calculated by the contact intensity calculation unit 154, and the sensing result by the force sensor 108. For example, the contact force calculation unit 156 calculates the contact force at each contact point using the calculation result by the contact point number calculation unit 150, the calculation result by the contact position calculation unit 152, and the calculation result by the contact intensity calculation unit 154 based on the determination result of whether or not the resultant force of the contact forces between the grip unit 104 and the object (i.e., the resultant force of the contact forces at each contact point) can be specified.
[0043] (2-2-5-1. Calculation example 1) As an example, when the resultant force of the contact forces between the gripper 104 and the object can be determined based on the sensing result by the force sensor 108, the contact force calculation unit 156 calculates the contact force at each contact point using the following calculation method. Note that a specific example of such a case is when the force sensor 108 is configured to include a three-axis force sensor, and the three-axis force sensor is disposed on the side of the gripper 104 opposite to the surface that grips the object.
[0044] - When there is one contact point For example, first, the contact force calculation unit 156 determines whether the total number of contact points calculated by the contact point number calculation unit 150 is one, two, or three or more. If the total number of contact points is one, the contact force calculation unit 156 calculates the resultant force sensed by the force sensor 108 as the contact force at the corresponding contact point.
[0045] - When there are two contact points Furthermore, when the total number of contact points is two, the contact force calculation unit 156 first calculates distances l1 and l2 from a predetermined reference position (such as an end point of the tactile sensor 106) to each contact point based on the position information of each contact point specified by the contact position calculation unit 152. Here, the contact forces at each contact point are defined as F1 and F2, and the resultant force of the contact forces sensed by the force sensor 108 is defined as Fall. In this case, the contact force calculation unit 156 calculates F1 and F2 from the following formulas (1) and (2), respectively.
[0046]
number
[0047] The relationship between Fall, F1, and F2 can be expressed by the following formula (3).
[0048]
number
[0049] - When the number of contact points is 3 or more Next, a method for calculating the contact force at each contact point when the total number of contact points is 3 or more will be described. Let N be the total number of contact points, Fi (i=1 to N) be the contact force at each contact point, αi (i=1 to N) be the contact force intensity ratio between each contact point calculated by the contact intensity calculation unit 154, and Fall be the resultant force of the contact forces sensed by the force sensor 108. In this case, the contact force calculation unit 156 calculates Fi using the following formula (4).
[0050]
number
[0051] The relationship between Fall and Fi can be expressed by the following formula (5).
[0052]
number
[0053] (2-2-5-2. Calculation example 2) Next, a method for calculating a contact force by the contact force calculation unit 156 will be described in a case where the resultant force of the contact forces between the gripper 104 and the object cannot be specified and the force generated by the actuator 130 (hereinafter, may be referred to as "τ") can be measured by the force sensor 108. Note that, as a specific example of such a case, a case where the force sensor 108 is configured to include a torque sensor and the torque sensor is disposed within the actuator 130, etc., can be mentioned.
[0054] - When there is one contact point In this case, the contact force calculation unit 156 calculates the contact force at each contact point by using, for example, the following calculation method. First, the contact force calculation unit 156 determines whether the total number of contact points calculated by the contact point number calculation unit 150 is one or two or more. If the total number of contact points is one, the contact force calculation unit 156 first calculates a distance l1 from a predetermined reference position (such as an end point of the tactile sensor 106) to the corresponding contact point based on the position information of each contact point specified by the contact position calculation unit 152. Then, the contact force calculation unit 156 calculates the contact force (F1) at the corresponding contact point by using the generated force (i.e. τ) of the actuator 130 sensed by the force sensor 108, l1, and the following formula (6).
[0055]
number
[0056] - When the number of contact points is 2 or more Next, a method for calculating the contact force at each contact point when the total number of contact points is two or more will be described. Let N be the total number of contact points, Fi (i=1 to N) be the contact force at each contact point, αi (i=1 to N) be the contact force intensity ratio between each contact point calculated by the contact intensity calculation unit 154, li (i=1 to N) be the distance from a predetermined reference position (e.g., an end point of the tactile sensor 106) to each contact point, and τ be the generated force of the actuator 130 sensed by the force sensor 108. In this case, the contact force calculation unit 156 calculates Fi using the following formula (7).
[0057]
number
[0058] The relationship between τ and Fi is as shown in the following formula (8).
[0059]
number
[0060] (2-2-5-3. Communication of calculation results) Furthermore, the contact force calculation unit 156 can transmit the calculated contact force at each contact point to the grip control unit 100.
[0061] {2-2-6. Slip detection unit 112} The slippage detection unit 112 may be configured to include the above-mentioned processing circuit. The slippage detection unit 112 may also be configured to further include the above-mentioned memory. The slippage detection unit 112 detects the amount of slippage of the object relative to the grip unit 104 while the grip unit 104 and the object are in contact with each other, based on the sensing result by the tactile sensor 106. For example, the slippage detection unit 112 detects the amount of slippage of the object based on the contact forces at the individual contact points calculated by the contact force identification unit 110 and the sensing result by the tactile sensor 106.
[0062] Here, in each embodiment, "slip" can mean a relative motion (relative deviation) between the surface of the gripping unit 104 and an object, and a precursor phenomenon of the occurrence of the relative motion. The precursor phenomenon is, for example, a phenomenon in which a part of the contact surface of the gripping unit 104 with the object slips or peels off (sometimes referred to as local slip). For example, the slip detection unit 112 may detect the amount of slip of the object (for example, the precursor phenomenon, etc.) based on the detection result of the CoP movement, the detection result of the change in the area of the contact region, or the detection result of the change in the contact position, etc.
[0063] In addition, the slippage detection unit 112 may transmit the detection result (for example, the detection result of the amount of slippage, the detection result of the presence or absence of slippage, and / or the amount of slippage-dependent change, etc.) to the grip control unit 100.
[0064] {2-2-7. Grip control unit 100} The grip control unit 100 may be configured to include the above-mentioned processing circuit. The grip control unit 100 may further include the above-mentioned memory. As shown in FIG. 2, the grip control unit 100 has a grip force calculation unit 102.
[0065] The grip control unit 100 controls the movement of the grip unit 104 based on a target grip force (i.e., the force with which the grip unit 104 grips the object) calculated by a grip force calculation unit 102 described below. For example, the grip control unit 100 controls the driving of the actuator 130 so as to bring the current grip force of the grip unit 104 closer to the target grip force calculated by the grip force calculation unit 102.
[0066] Furthermore, the grip control unit 100 can perform known feedback control on the grip unit 104 based on the sensing results successively acquired from the force sensor 108.
[0067] {2-2-8. Grip force calculation unit 102} The gripping force calculation unit 102 calculates a target gripping force for the gripping unit 104 based on the contact forces at individual contact points calculated by the contact force identification unit 110 and the amount of slippage of the object to be grasped detected by the slippage detection unit 112.
[0068] For example, when slippage detection unit 112 detects the occurrence of slippage, grip force calculation unit 102 calculates a target grip force that is greater than the current grip force of grip unit 104 and corresponds to the amount of slippage detected by slippage detection unit 112. When slippage detection unit 112 detects that the currently occurring slippage has stopped, grip force calculation unit 102 calculates a target grip force of grip unit 104 (from the present onward) so that the grip force of grip unit 104 gradually decreases.
[0069] <2-3. Processing flow> The functional configuration of the robot 10 according to the first embodiment has been described above. Next, a process flow according to the first embodiment will be described with reference to FIG. 4. FIG. 4 is a flowchart showing an example of the process flow according to the first embodiment. Below, an example of the process flow in a scene where the robot 10 grasps a target object will be described.
[0070] 4, first, the contact force specifying unit 110 of the robot 10 detects whether or not the gripping unit 104 has come into contact with a target object based on the sensing result by the tactile sensor 106 (S101). If the gripping unit 104 has not come into contact with the target object (S101: No), the contact force specifying unit 110 repeats the process of S101 after, for example, a predetermined time has elapsed.
[0071] On the other hand, when it is detected that the gripping portion 104 has come into contact with the target object (S101: Yes), the contact force identification unit 110 calculates the total number of contact points between the gripping portion 104 and the object, the positional information of each contact point, and the contact intensity ratio between each contact point based on the sensing results by the tactile sensor 106 (S103).
[0072] Next, the contact force identification unit 110 calculates the contact force at each contact point based on the calculation result in S103 and the sensing result by the force sensor 108 (for example, the most recent sensing result at the time of S101) (S105).
[0073] Next, the slippage detection unit 112 detects the amount of slippage of the object relative to the gripping unit 104 based on the contact force at each contact point calculated in S105 and the sensing result by the tactile sensor 106 (for example, the sensing result at the most recent time point S101) (S107).
[0074] Next, grip force calculation unit 102 calculates a target grip force of grip unit 104 based on the contact force at each contact point calculated in S105 and the amount of slippage of the object detected in S107. For example, grip force calculation unit 102 calculates a force to be generated by actuator 130 based on the contact force at each contact point and the amount of slippage of the object detected so that the grip force of grip unit 104 reaches the target grip force (S109).
[0075] Thereafter, the grip control unit 100 controls the driving of the actuator 130 based on the target grip force (or the force to be generated by the actuator 130) calculated in S109 (S111).
[0076] <2-4.Effects> {2-4-1. Effect 1} As described above, the robot 10 according to the first embodiment calculates the contact force when the gripper 104 comes into contact with an object based on the sensing result by the tactile sensor 106 arranged in the gripper 104 and the sensing result by the force sensor 108 arranged in the gripper 104. As described above, according to the first embodiment, since both the sensing result by the tactile sensor 106 and the sensing result by the force sensor 108 are used, the contact force when the gripper 104 comes into contact with an object can be calculated with higher accuracy. For example, when the gripper 104 comes into contact with an object at a plurality of contact points, the contact force at each contact point can be calculated with higher accuracy. In addition, the calculation algorithm for the contact force can be changed robustly depending on the sensor type and arrangement of the tactile sensor 106.
[0077] {2-4-2. Effect 2} Furthermore, according to the first embodiment, since the contact force when the gripper 104 contacts an object can be calculated with high accuracy, the amount of slippage of the object relative to the gripper 104 can be detected with high accuracy. For example, slippage that varies depending on the magnitude of the contact force can be detected with high accuracy. Furthermore, the improved accuracy of slippage detection enables the gripper 104 to grip an object with less force. For example, even if the reaction force from the object to be gripped, such as a soft object or a fragile object, is small, the gripper 104 can grip the object safely.
[0078] {2-4-3. Effect 3} Furthermore, since the contact force when the gripper 104 comes into contact with an object can be calculated with high accuracy, the timing of contact between the gripper 104 and the object can also be detected more accurately. For example, according to the first embodiment, since not only the sensing result by the tactile sensor 106 but also the sensing result by the force sensor 108 are used simultaneously, the contact sensitivity (e.g., the contact sensitivity of the tip (e.g., fingertip) of the gripper 104) can be improved compared to existing techniques. This allows the timing of contact to be detected more accurately.
[0079] As a result, the following three advantages are obtained. First, the gripping unit 104 can grip the object more appropriately. Second, for example, it becomes possible to flexibly adjust the timing of the start of the slippage detection process by the slippage detection unit 112. As a result, it becomes possible to reduce the processing load of the robot 10 during periods other than the period when the gripping unit 104 is gripping the object.
[0080] Thirdly, since the contact timing can be detected more accurately, in a situation where the robot 10 switches control at the contact timing, the control can be switched to a more accurate timing. For example, in a situation where the control method or parameters (e.g., target values of speed and force, etc.) are changed at the contact timing (e.g., the opening and closing operation of the gripper 104 is temporarily stopped at the contact timing), the robot 10 can change them to a more accurate timing. Therefore, compared with the existing technology, it becomes possible to deal with various situations more widely and more appropriately. For example, the robot 10 can safely grip the object without knocking it over or moving it. In addition, in a situation where a task of gripping an object directly handed over by a human or another robot is performed, the grip timing can be set more appropriately, so the robot 10 can perform the task more appropriately.
[0081] {2-4-4. Effect 4} Moreover, according to the first embodiment, the contact force can be calculated more accurately even in the case of multi-point contact. As a result, the following three effects can be obtained. First, even if the object to be grasped has a complex shape, the object can be grasped safely without being destroyed. Second, even if the object to be grasped has a complex shape, the amount of slippage of the object can be appropriately detected. Therefore, the robot 10 can grasp the object safely without the object slipping off. Third, even if slippage occurs at one or more of all the corresponding contact points, the slippage can be detected with high accuracy. Therefore, the object can be grasped more safely.
[0082] {2-4-5. Effect 5} Furthermore, according to the first embodiment, various types of sensors, such as a pressure distribution sensor or a vision sensor, can be used as the tactile sensor 106, and there is a wide range of sensor types to choose from. Therefore, it is possible to select an appropriate processing method according to the form of the robot 10 and the form of the sensor mounted on the robot 10.
[0083] {2-4-6. Effect 6} Moreover, according to the first embodiment, even if an object comes into contact at any position within an area that can be sensed by the tactile sensor 106, the contact force at each contact point can be calculated. Therefore, position adjustment may not be necessary when the gripper 104 grips an object. As a result, the following three effects can be obtained. First, the target object can be gripped more quickly. Second, it is not necessary to additionally mount a sensor (such as a camera) for position adjustment on the robot 10. Third, the allowable range of error due to bending of the structure supporting the gripper 104 can be increased. Therefore, it is also possible to reduce the strength of the corresponding structure, which allows the robot 10 to be made lighter and less expensive.
[0084] <<3. Second embodiment>> The first embodiment has been described above. Next, a second embodiment according to the present disclosure will be described. As will be described later, according to the second embodiment, the user can specify an upper limit value of the contact force between the gripper 104 and an object. The physical configuration of the robot 10 according to the second embodiment may be the same as that of the first embodiment shown in FIG. 1. Also, with regard to the third to ninth embodiments described later, the physical configuration of the robot 10 may be the same as that of the first embodiment. Hereinafter, only the differences from the first embodiment will be described, and the same contents will not be described.
[0085] <3-1. Functional configuration> Next, the functional configuration of the robot 10 according to the second embodiment will be described with reference to Fig. 5. Fig. 5 is a block diagram showing an example of the functional configuration of the robot 10 according to the second embodiment. As shown in Fig. 5, the robot 10 according to the second embodiment further includes a contact force threshold storage unit 200, compared to the first embodiment shown in Fig. 2.
[0086] {3-1-1. Contact force threshold storage unit 200} The contact force threshold storage unit 200 stores an upper limit of the contact force when the grip unit 104 comes into contact with an object (hereinafter referred to as the "upper limit specified value of the contact force"), which is specified in advance by the user. This upper limit specified value of the contact force may be the same value, independent of the type of object to be gripped.
[0087] {3-1-2. Grip force calculation unit 102} The grip force calculation unit 102 according to the second embodiment calculates a target grip force of the grip unit 104 (from the present onwards) based on the upper limit designated value of the contact force stored in the contact force threshold storage unit 200. For example, the grip force calculation unit 102 calculates the upper limit value of the force to be generated by the actuator 130 so that the contact force at each contact point between the grip unit 104 and the object is equal to or less than the upper limit designated value of the contact force stored in the contact force threshold storage unit 200.
[0088] <3-2.Effects> As described above, according to the second embodiment, the user can specify the upper limit of the contact force between the gripper 104 and an object. Therefore, the robot 10 can control the contact force so that it does not become excessive, and can safely grip even a soft object or a fragile object, for example. Furthermore, the grip strength can be changed depending on the application implemented in the robot 10 and the situation at hand.
[0089] It is preferable that a user interface capable of specifying the grip strength of the gripping portion 104 and the robot 10 are configured to be able to cooperate with each other via a predetermined network (such as the Internet or a public network). With such a configuration, the user can more easily specify the desired grip strength.
[0090] <<4. Third embodiment>> The second embodiment has been described above. Next, a third embodiment according to the present disclosure will be described. As described later, according to the third embodiment, the upper limit value of the contact force between the gripper 104 and an object can be appropriately specified for each type of object. In the following, only the contents different from the second embodiment will be described, and the same contents will not be described.
[0091] <4-1. Functional configuration> Fig. 6 is a block diagram showing an example of a functional configuration of the robot 10 according to the third embodiment. As shown in Fig. 6, the robot 10 according to the third embodiment further includes an object recognition unit 202, compared to the second embodiment shown in Fig. 5.
[0092] {4-1-1. Object recognition unit 202} The object recognition unit 202 may be configured to include a sensor for object recognition (e.g., an image sensor (camera) or an infrared sensor). The object recognition unit 202 senses each object located around the robot 10 (e.g., within the movable range of the grip unit 104), and recognizes the type of each object based on the sensing result.
[0093] {4-1-2. Contact force threshold storage unit 200} The contact force threshold storage unit 200 according to the third embodiment stores an upper limit of the contact force between the grip unit 104 and an object for each type of object, which is designated in advance by, for example, a user.
[0094] {4-1-3. Grip force calculation unit 102} The gripping force calculation unit 102 according to the third embodiment calculates a target gripping force of the gripping unit 104 (or an upper limit of the force to be generated by the actuator 130) based on the type of object to be gripped recognized by the object recognition unit 202 and the upper limit of the contact force of the corresponding object stored in the contact force threshold memory unit 200.
[0095] <4-2.Effects> As described above, according to the third embodiment, the upper limit of the contact force between the gripper 104 and an object can be appropriately specified for each type of object. Therefore, the robot 10 can grip the object with a force appropriate for the type of object to be gripped, and can grip the object more safely. Furthermore, according to the third embodiment, the user does not need to specify the upper limit of the contact force each time, and the number of operations can be reduced.
[0096] <<5. Fourth embodiment>> The third embodiment has been described above. Next, a fourth embodiment according to the present disclosure will be described. As described later, according to the fourth embodiment, the upper limit value of the contact force between the gripping unit 104 and an object can be appropriately specified according to past gripping experience. In the following, only the contents different from the third embodiment will be described, and the same contents will not be described.
[0097] <5-1. Functional configuration> Fig. 7 is a block diagram showing an example of a functional configuration of the robot 10 according to the fourth embodiment. As shown in Fig. 7, the robot 10 according to the fourth embodiment further includes a contact force upper limit specifying unit 204, compared to the third embodiment shown in Fig. 6.
[0098] {5-1-1. Contact force threshold storage unit 200} The contact force threshold memory unit 200 according to the fourth embodiment can store, in association with each other, the type of object recognized by the object recognition unit 202 when it was previously grasped, the state of the object at the time of the grasping (e.g., whether it was destroyed or not), and the gripping force of the gripping unit 104 at the time of the grasping.
[0099] Furthermore, for each type of object, an upper limit of the contact force within a range in which the object is not destroyed when the object comes into contact with the gripper 104 can be specified in advance based on this information. In this case, the contact force threshold storage unit 200 may further store an upper limit of the contact force within a range in which the object is not destroyed for each type of object.
[0100] {5-1-2. Contact force upper limit specification section 204} The contact force upper limit determination unit 204 determines an upper limit value of the contact force within a range in which the object to be grasped will not be destroyed, based on the type of object to be grasped recognized by the object recognition unit 202 and the information stored in the contact force threshold memory unit 200.
[0101] {5-1-3.Gripping force calculation unit 102} The grip force calculation unit 102 according to the fourth embodiment calculates a target grip force of the grip unit 104 (or an upper limit value of the force to be generated by the actuator 130) based on the upper limit value of the contact force identified by the contact force upper limit identification unit 204 and the contact force at each contact point identified by the contact force identification unit 110.
[0102] <5-2.Effects> {5-2-1. Effect 1} As described above, according to the fourth embodiment, the upper limit of the contact force between the gripping unit 104 and an object can be appropriately specified according to past gripping experience. For example, the robot 10 can set the upper limit of the contact force when the object to be gripped was successfully gripped in the past as the upper limit of the contact force between the gripping unit 104 and the object. This allows the robot 10 to grip each object more reliably. In addition, the robot 10 can determine the possibility of gripping the object while gripping the object. For example, if it is detected that the object continues to slip even when the upper limit of the contact force of the object is added, the robot 10 can determine that the friction coefficient of the object is too small and therefore gripping the object is impossible or difficult.
[0103] {5-2-2. Effect 2} Furthermore, according to the fourth embodiment, manual work is not required to determine the upper limit of the contact force. For example, the user does not need to carry out research or data collection for determining the upper limit of the contact force, which makes it easier to introduce the system.
[0104] <<6. Fifth embodiment>> The fourth embodiment has been described above. Next, a fifth embodiment according to the present disclosure will be described. As described later, according to the fifth embodiment, the user can easily specify the upper limit of the contact force between the gripper 104 and the object, or the target value of the contact force. In the following, only the differences from the first embodiment will be described, and the same contents will not be described.
[0105] <6-1. Functional configuration> Fig. 8 is a block diagram showing an example of a functional configuration of the robot 10 according to the fifth embodiment. As shown in Fig. 8, the robot 10 according to the fifth embodiment further includes an input unit 206, compared to the first embodiment shown in Fig. 2.
[0106] {6-1-1. Input section 206} The input unit 206 may be configured to include an input device (e.g., a mouse, a keyboard, or a touch panel) or may be configured to include a voice input device (e.g., a microphone). The input unit 206 accepts various inputs to the robot 10 from the user.
[0107] (6-1-1-1. Input example 1) For example, the input unit 206 may receive an input of an upper limit value of the contact force from the user before each time the grip unit 104 grips an object. As an example, the user may input a multiplier for a reference value of the contact force to the input unit 206, or may input any one of a plurality of levels of contact force that are prepared in advance to the input unit 206. In these cases, the input information to the input unit 206 is transmitted to the grip control unit 100, and the grip control unit 100 may determine the upper limit value of the actual contact force based on the input information.
[0108] (6-1-1-2. Input example 2) Alternatively, the input unit 206 may receive a target value of the contact force input by the user. In this case, the grip force calculation unit 102 may calculate a force (target value) that the actuator 130 should generate so that the current contact force of the grip unit 104 is equal to the input target value of the contact force.
[0109] <6-2.Effects> {6-2-1. Effect 1} As described above, according to the fifth embodiment, the user can easily specify the upper limit of the contact force between the gripper 104 and an object. For example, the user can specify the upper limit of the contact force each time (for example, in real time). As a result, the robot 10 can respond immediately and robustly to changes in the situation or applications at the time. Also, the user can intuitively input the upper limit of the contact force.
[0110] {6-2-2. Effect 2} Furthermore, according to the fifth embodiment, the user can easily specify a target value of the contact force between the gripping unit 104 and an object. For example, the user can specify the target value of the contact force each time (for example, in real time). Also, when using an application that applies a certain contact force to an object, the user can specify a desired contact force.
[0111] <<7. Sixth embodiment>> The fifth embodiment has been described above. Next, the sixth embodiment according to the present disclosure will be described. As described later, according to the sixth embodiment, the upper limit value of the contact force can be appropriately adjusted depending on the state of the object when it is grasped. In the following, only the contents different from the first embodiment will be described, and the same contents will not be described.
[0112] <7-1. Functional configuration> Fig. 9 is a block diagram showing an example of a functional configuration of the robot 10 according to the sixth embodiment. As shown in Fig. 9, the robot 10 according to the sixth embodiment further includes a contact force upper limit specifying unit 204 and a gripping state recognizing unit 208, compared to the first embodiment shown in Fig. 2.
[0113] {7-1-1. Gripping state recognition unit 208} The grip state recognition unit 208 may be configured to include a sensor for recognizing the grip state (e.g., an image sensor (camera) or an infrared sensor). The grip state recognition unit 208 senses the object gripped by the grip unit 104, and may recognize the state of the object (e.g., whether or not it is destroyed, whether or not it is deformed, etc.) based on the sensing result, for example, in real time.
[0114] {7-1-2. Contact force upper limit specification section 204} The contact force upper limit identification unit 204 according to the sixth embodiment calculates, for example in real time, an upper limit value of the contact force between the gripping unit 104 and the object based on the recognition result of the state of the target object by the gripping state recognition unit 208 and the current contact force between the gripping unit 104 and the object calculated by the contact force identification unit 110.
[0115] <7-2.Effects> As described above, according to the sixth embodiment, the upper limit of the contact force can be appropriately adjusted according to the state of the object being grasped. For example, even if the object is deformed or broken in a way that cannot be predicted in advance, the robot 10 can respond to such events in real time by adjusting the upper limit of the contact force in real time.
[0116] The robot 10 according to the sixth embodiment may recognize in advance whether or not an object being grasped by the grasper 104 (or the robot 10 itself) is likely to come into contact with the external environment (e.g., a human being or an obstacle). In this case, in order to prevent the object from slipping off due to the contact, the robot 10 may adjust the contact force based on the recognition result as an anti-slip operation.
[0117] <<8. Seventh embodiment>> The sixth embodiment has been described above. Next, the seventh embodiment according to the present disclosure will be described. As described later, according to the seventh embodiment, it is possible to appropriately switch whether or not to perform slippage detection processing depending on the detection result of contact between the grip unit 104 and an object. In the following, only the contents different from the first embodiment will be described, and the same contents will not be described.
[0118] <8-1.Functional Configuration> Fig. 10 is a block diagram showing an example of a functional configuration of the robot 10 according to the seventh embodiment. As shown in Fig. 10, the robot 10 according to the seventh embodiment further includes a contact detection unit 210, compared to the first embodiment shown in Fig. 2.
[0119] {8-1-1. Contact detection unit 210} The contact detection unit 210 detects whether or not the grip unit 104 is in contact with an object based on the calculation result by the contact force identification unit 110. Furthermore, the contact detection unit 210 may output a contact trigger to the slippage detection unit 112 when it detects the start of contact between the grip unit 104 and an object.
[0120] {8-1-2. Slip detection unit 112} The slippage detection unit 112 according to the seventh embodiment determines whether or not to perform a process for detecting the amount of slippage, based on the detection result by the contact detection unit 210. For example, the slippage detection unit 112 performs the slippage detection process only while the contact between the grip unit 104 and an object is detected by the contact detection unit 210. In other words, the slippage detection unit 112 does not perform the slippage detection process while the contact between the grip unit 104 and an object is not detected by the contact detection unit 210. For example, the slippage detection unit 112 may start the slippage detection process only when a contact trigger is received from the slippage detection unit 112.
[0121] <8-2.Effects> As described above, according to the seventh embodiment, it is possible to appropriately switch whether or not to perform slippage detection processing depending on the detection result of contact between the grip portion 104 and an object.
[0122] Generally, slippage detection processing requires processing the values of each sensor in the entire area of the tactile sensor 106, which imposes a large processing load. According to the seventh embodiment, it is possible to perform slippage detection processing only while contact between the grip unit 104 and an object is detected, which reduces the processing load while contact between the grip unit 104 and an object is not detected. As a result, it is possible to reduce memory usage and power consumption.
[0123] <<9. Eighth embodiment>> The seventh embodiment has been described above. Next, an eighth embodiment according to the present disclosure will be described. As described later, according to the eighth embodiment, the type of control to be executed or the value of the control parameter can be appropriately switched before and after contact between the gripper 104 and an object. In the following, only the contents different from the first embodiment will be described, and the same contents will not be described.
[0124] <9-1. Functional configuration> Fig. 11 is a block diagram showing an example of a functional configuration of the robot 10 according to the eighth embodiment. As shown in Fig. 11, the robot 10 according to the eighth embodiment further includes a contact detection unit 210 and a main body control unit 212, compared to the first embodiment shown in Fig. 2.
[0125] {9-1-1. Contact detection unit 210} The contact detection section 210 according to the eighth embodiment can output a contact trigger to the grip control section 100 and the main body control section 212 when detecting the start of contact between the grip section 104 and an object.
[0126] {9-1-2. Main body control unit 212} The main body control unit 212 controls the operation of the main body unit of the robot 10 (for example, one or more joints included in a portion other than the grip unit 104) based on the detection result by the contact detection unit 210. For example, the main body control unit 212 switches the type of control performed on the main body unit of the robot 10 and / or the control parameters related to the main body unit of the robot 10 depending on whether or not the contact detection unit 210 detects contact between the grip unit 104 and an object. Here, the type of control may include, for example, position control or force control. Furthermore, the control parameters may include, for example, mechanical impedance, control gain, position, force, speed, torque, or other command values. Furthermore, the control parameters may further include upper and lower limit values of these parameters.
[0127] For example, until contact between the gripper 104 and the object is detected by the contact detection unit 210, the main body control unit 212 performs only position control on the main body of the robot 10. After the contact detection unit 210 detects contact between the gripper 104 and the object, the main body control unit 212 may switch the type of control to perform force control instead of position control on the main body of the robot 10.
[0128] Alternatively, the main body control unit 212 does not change the value of the control parameter related to the main body of the robot 10 until the contact detection unit 210 detects the contact between the gripper 104 and the object. After the contact detection unit 210 detects the contact between the gripper 104 and the object, the main body control unit 212 may switch the value of the control parameter related to the main body of the robot 10, for example, according to the detection result. For example, when the contact between the gripper 104 and the object is detected, the main body control unit 212 may lower the control gain for the main body of the robot 10 so that the main body of the robot 10 moves while suppressing sudden changes. Alternatively, when the contact is detected, the main body control unit 212 may change the mechanical impedance setting value of the main body of the robot 10 so that the movement of the main body of the robot 10 becomes more flexible.
[0129] Alternatively, the main body control unit 212 may keep the type of control over the main body of the robot 10 at force control, and change the mechanical impedance setting (an example of a control parameter) of the main body of the robot 10 at the timing of contact between the gripper 104 and an object.
[0130] {9-1-3. Grip control unit 100} The grip control unit 100 according to the eighth embodiment controls the operation of the grip unit 104 based on the detection result by the contact detection unit 210. For example, the grip control unit 100 switches the type of control performed on the grip unit 104 and / or the control parameters related to the grip unit 104 depending on whether or not the contact detection unit 210 detects contact between the grip unit 104 and an object. Note that the specific content of the type of control and the control parameters may be similar to the content described above (in relation to the main body control unit 212).
[0131] For example, until contact between the grip unit 104 and an object is detected by the contact detection unit 210, the grip control unit 100 performs only position control on the grip unit 104. After the contact detection unit 210 detects contact between the grip unit 104 and the object, the grip control unit 100 may switch the type of control to perform force control on the grip unit 104 instead of position control.
[0132] <9-2.Effects> As described above, according to the eighth embodiment, the type of control to be executed or the value of the control parameter can be appropriately switched before and after contact between the grip portion 104 and an object.
[0133] <<10. Ninth embodiment>> The eighth embodiment has been described above. Next, a ninth embodiment according to the present disclosure will be described. As will be described later, according to the ninth embodiment, the amount of slippage of an object relative to the grip unit 104 can be detected by simultaneously using not only the sensing result by the tactile sensor 106 but also the sensing result by the force sensor 108. In the following, only the contents different from the first embodiment will be described, and the same contents will not be described.
[0134] <10-1.Function configuration> Fig. 12 is a block diagram showing an example of a functional configuration of the robot 10 according to the ninth embodiment. As shown in Fig. 12, the ninth embodiment differs from the first embodiment shown in Fig. 2 only in that the force sensor 108 and the slippage detection unit 112 are connected.
[0135] The slippage detection unit 112 of the ninth embodiment detects the amount of slippage of the object while it is in contact with the gripper 104, based on the contact force at each contact point calculated by the contact force identification unit 110, the sensing results by the tactile sensor 106, and the sensing results by the force sensor 108.
[0136] <<11. Modifications>> Although the preferred embodiment of the present disclosure has been described in detail above with reference to the accompanying drawings, the present disclosure is not limited to such examples. It is clear that a person having ordinary knowledge in the technical field to which the present disclosure belongs can conceive of various modified or amended examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally belong to the technical scope of the present disclosure.
[0137] <11-1. Variation 1> For example, the main body control unit 212 according to the eighth embodiment is not limited to an example in which only the robot 10 according to the eighth embodiment has the main body control unit 212. The robot 10 according to any other embodiment may also have the main body control unit 212 in the same manner.
[0138] <11-2. Variation 2> As another modification, in each of the above-described embodiments, an example in which the contact portion according to the present disclosure is the gripping portion 104 has been described, but the present disclosure is not limited to such an example. For example, the contact portion is not necessarily limited to an example having a configuration capable of gripping an object, but may have a configuration capable of contacting an object. As an example, the robot 10 may be capable of pressing the contact portion against an object or of pulling the object. For example, the contact portion may be the surface of any part of the robot 10 (e.g., the torso, the arm, or the leg, etc.).
[0139] <11-3. Variation 3> As another modified example, in each of the above-described embodiments, an example has been described in which the control device according to the present disclosure is the robot 10, but the present disclosure is not limited to such an example, and the control device may be a device different from the robot 10. For example, the control device may be a server, a general-purpose PC (Personal Computer), a tablet terminal, a game machine, a mobile phone such as a smartphone, a wearable device such as an HMD (Head Mounted Display) or a smart watch, an in-vehicle device (such as a car navigation device), or another robot (such as a humanoid robot or a drone).
[0140] In this case, the control device can control the behavior of the robot 10 through the above-mentioned predetermined network. For example, the control device can first receive the sensing results from the tactile sensor 106 and the force sensor 108 from the robot 10, and then calculate the contact force at each contact point when the gripper 104 comes into contact with an object based on these sensing results.
[0141] <11-4. Variation 4> Furthermore, each step in the above-mentioned process flow does not necessarily have to be processed in the order described. For example, each step may be processed in a different order as appropriate. Each step may be partially processed in parallel or individually instead of being processed in chronological order. Some of the steps described may be omitted, or other steps may be added.
[0142] Furthermore, according to each of the above-described embodiments, it is possible to provide a computer program for causing hardware such as a CPU, a ROM, and a RAM to perform functions equivalent to those of the components of the robot 10 according to each of the above-described embodiments (e.g., the contact force identification unit 110, the slippage detection unit 112, and the grip control unit 100). Also provided is a storage medium on which the computer program is recorded.
[0143] In addition, the effects described in this specification are merely descriptive or exemplary and are not limiting. In other words, the technology according to the present disclosure may achieve other effects that are apparent to a person skilled in the art from the description of this specification, in addition to or in place of the above effects.
[0144] Note that the following configurations also fall within the technical scope of the present disclosure. (1) a gripping control unit that controls a gripping force associated with the contact portion in accordance with a contact force when the contact portion comes into contact with an object, the contact force being based on a sensing result by a tactile sensor disposed in the contact portion and a sensing result by a force sensor disposed in the contact portion; A control device comprising: (2) The contact portion is a grip portion, The control device described in (1), wherein the gripping control unit controls the gripping force of the gripping unit in accordance with information regarding each contact point when the gripping unit and the object come into contact at one or more points, which is identified from the sensing result by the tactile sensor, and the contact force at each contact point calculated based on the sensing result by the force sensor. (3) The control device according to (2), wherein the information regarding the individual contact points includes a total number of the individual contact points and information indicating a positional relationship of the individual contact points. (4) The control device described in (3), wherein the information about the individual contact points further includes a contact strength ratio between the individual contact points. (5) The control device according to (4), wherein the information indicating the positional relationship of the individual contact points includes position information of the individual contact points within the gripping portion. (6) The control device according to (4) or (5), wherein the gripping control unit controls the gripping force of the gripping unit in accordance with the contact force at each of the contact points calculated based on information regarding the individual contact points and the resultant contact force between the gripping unit and the object, as determined from the sensing results of the force sensor. (7) The gripping portion is connected to an actuator or includes an actuator; The control device described in (4) or (5), wherein the gripping control unit controls the gripping force of the gripping unit in accordance with the contact force at each contact point when the gripping unit and the object come into contact at one or more points, the contact force being calculated based on information about the individual contact points and the generated force of the actuator identified from the sensing results of the force sensor. (8) The control device according to any one of (4) to (7), further comprising a contact force calculation unit that calculates a contact force at each of the contact points based on information about each of the contact points and a sensing result by the force sensor. (9) The control device according to (8), further comprising a slippage detection unit that detects an amount of slippage of the object relative to the gripping unit based on a sensing result by the tactile sensor. (10) The control device described in (9), wherein the slippage detection unit further detects an amount of slippage of the object relative to the gripping unit based on the contact forces at the individual contact points calculated by the contact force calculation unit. (11) The control device according to (10), wherein the slippage detection unit further detects an amount of slippage of the object relative to the gripping unit based on a sensing result by the force sensor. (12) The control device according to (10) or (11), further comprising: a slippage detection unit that determines whether or not to detect an amount of slippage of the object relative to the gripping portion based on whether or not contact between the gripping portion and the object is detected. (13) The control device according to any one of (9) to (12), wherein the grip control unit controls the grip force of the grip unit in accordance with the contact force at each contact point calculated by the contact force calculation unit and the amount of slippage detected by the slippage detection unit. (14) The control device according to (13), wherein the grip control unit further controls the grip force of the grip portion according to an upper limit value of the contact force when the grip portion comes into contact with the object, the upper limit value being specified by a user. (15) The control device according to (13) or (14), wherein the grip control unit further controls the gripping force of the gripping unit according to a target value of a contact force of the gripping unit against the object, the target value being specified by a user. (16) The control device according to any one of (13) to (15), wherein the gripping control unit further controls the gripping force of the gripping unit in accordance with information indicating a relationship between a state of the object when the gripping unit previously gripped the object and the gripping force of the gripping unit. (17) The control device according to any one of (13) to (16), wherein the gripping control unit further controls the gripping force of the gripping unit according to a recognition result of a state of the object while the gripping unit is in contact with the object. (18) The control device according to any one of (13) to (17), wherein the grip control unit further switches a type of control performed on the grip unit or a control parameter related to the grip unit depending on whether or not contact between the grip unit and the object is detected. (19) a processor controls a gripping force associated with the contact portion in response to a contact force when the contact portion comes into contact with an object, the contact force being based on a sensing result by a tactile sensor disposed on the contact portion and a sensing result by a force sensor disposed on the contact portion; A control method comprising: (20) Computer, a gripping control unit that controls a gripping force associated with the contact portion in accordance with a contact force when the contact portion comes into contact with an object, the contact force being based on a sensing result by a tactile sensor disposed in the contact portion and a sensing result by a force sensor disposed in the contact portion; A program to function as a [Explanation of symbols]
[0145] 10. Robot 100 Grip control section 102 Gripping force calculation unit 104 Gripping part 106 Tactile Sensor 108 Force Sensor 110 Contact force identification part 112 Slip detection unit 130 Actuator 150 Contact point number calculation unit 152 Contact position calculation section 154 Contact strength calculation unit 156 Contact force calculation section 200 Contact force threshold memory unit 202 Object recognition section 204 Contact force upper limit specification section 206 Input section 208 Grasping state recognition unit 210 Contact detection unit 212 Main unit control section
Claims
1. when the processor controls a gripping force associated with the gripping portion based on a sensing result by a tactile sensor disposed in the gripping portion, the processor controls the gripping force of the gripping portion in accordance with information on individual contact points identified from the sensing result by the tactile sensor when the gripping portion and an object come into contact with each other at one or more points; Including, The information about the individual contact points includes a total number of the individual contact points, information indicating a positional relationship between the individual contact points, and a contact intensity ratio between the individual contact points, The controlling includes controlling the gripping force of the gripping unit based on a type of the object, a state of the object, and a gripping force by the gripping unit when the gripping unit previously gripped the object. Control methods.
2. The information indicating the positional relationship of each of the contact points includes position information of each of the contact points within the grip portion. The control method according to claim 1 .
3. the processor controls the gripping force of the gripping unit in response to the contact force at each of the contact points calculated based on information about each of the contact points and a resultant force of contact forces between the gripping unit and the object, the resultant force being determined from a sensing result by a force sensor disposed on the gripping unit. The control method according to claim 1 .
4. The gripping portion is connected to an actuator or includes an actuator; the processor controls the gripping force of the gripping unit in response to a contact force at each contact point when the gripping unit and the object come into contact with each other at one or more points, the contact force being calculated based on information about each contact point and a generated force of the actuator identified from a sensing result by a force sensor disposed on the gripping unit. The control method according to claim 1 .
5. the processor calculates a contact force at each of the contact points based on information about each of the contact points and a sensing result by a force sensor disposed in the gripping portion. The control method according to claim 1 .
6. The processor detects an amount of slippage of the object relative to the gripping unit based on a sensing result by the tactile sensor. The control method according to claim 5.
7. the processor detects an amount of slippage of the object relative to the gripper based on the contact forces at the individual contact points. The control method according to claim 6.
8. The processor detects an amount of slippage of the object relative to the gripping unit based on a sensing result by the force sensor. The control method according to claim 7.
9. the processor determines whether to detect an amount of slippage of the object relative to the gripper based on whether contact between the gripper and the object is detected; The control method according to claim 7.
10. The processor controls the gripping force of the gripping part according to the contact force at each of the contact points and the amount of slippage. The control method according to claim 6.
11. The processor controls the gripping force of the gripping unit according to an upper limit value of a contact force when the gripping unit comes into contact with the object, the upper limit value being specified by a user. The control method according to claim 10.
12. The processor controls a gripping force of the gripping unit in accordance with a target value of a contact force of the gripping unit with respect to the object, the target value being specified by a user. The control method according to claim 10.
13. the processor controls the gripping force of the gripping unit in response to information indicating a relationship between a state of the object when the gripping unit previously gripped the object and a gripping force of the gripping unit. The control method according to claim 10.
14. The processor controls a gripping force of the gripping unit according to a recognition result of a state of the object while the gripping unit is in contact with the object. The control method according to claim 10.
15. The processor switches a type of control performed on the gripping unit or a control parameter related to the gripping unit depending on whether or not contact between the gripping unit and the object is detected. The control method according to claim 10.
16. a grip control unit that, when controlling a grip force related to the grip unit based on a sensing result by a tactile sensor arranged in the grip unit, controls the grip force of the grip unit in accordance with information on individual contact points when the grip unit and an object come into contact with each other at one or more points, the information being identified from the sensing result by the tactile sensor; Equipped with The information about the individual contact points includes a total number of the individual contact points, information indicating a positional relationship between the individual contact points, and a contact intensity ratio between the individual contact points, the gripping control unit controls the gripping force of the gripping unit based on a type of the object, a state of the object, and a gripping force by the gripping unit when the gripping unit previously gripped the object. Control system.
17. Computer, when controlling a gripping force related to the gripping portion based on a sensing result by a tactile sensor disposed in the gripping portion, the gripping force of the gripping portion is controlled in accordance with information on individual contact points when the gripping portion and an object come into contact with each other at one or more points, the information being identified from the sensing result by the tactile sensor; The information about the individual contact points includes a total number of the individual contact points, information indicating a positional relationship between the individual contact points, and a contact intensity ratio between the individual contact points. Grip control unit, Function as a the gripping control unit controls the gripping force of the gripping unit based on a type of the object, a state of the object, and a gripping force by the gripping unit when the gripping unit previously gripped the object. Program for.
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