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JP-2026075315-A - Gripping mechanism and gripping method

JP2026075315AJP 2026075315 AJP2026075315 AJP 2026075315AJP-2026075315-A

Abstract

[Problem] To provide a gripping mechanism and gripping method that enable high-quality gripping. [Solution] The device comprises a first base portion 11, a fixed finger 10, a second base portion 21, a first linear motion mechanism 40 for sliding the second base portion 21 relative to the first base portion 11, a movable finger 20 having a base portion rotatably connected to the second base portion and a tip portion rotatably connected to the base portion, a second linear motion mechanism attached to the second base portion, and a link mechanism provided between the movable finger and the second base portion so as to change the angle of the base portion relative to the fixed finger and the angle of the tip portion relative to the base portion by the operation of the second linear motion mechanism. [Selection Diagram] Figure 1

Inventors

  • 手嶋（康） 天毅

Assignees

  • トヨタ自動車株式会社

Dates

Publication Date
20260508
Application Date
20241022

Claims (5)

  1. First base section, A fixing finger fixed to the first base portion, A second base portion is provided so as to be movable relative to the first base portion, A first linear motion mechanism is attached to the first base portion and slides the second base portion relative to the first base portion, A movable finger having a base portion rotatably connected to the second base portion and a tip portion rotatably connected to the base portion, The second linear motion mechanism attached to the second base portion, A gripping mechanism comprising a link mechanism provided between the movable finger and the second base portion, such that the operation of the second linear motion mechanism changes the angle of the base portion relative to the fixed finger and also changes the angle of the tip portion relative to the base portion.
  2. The link mechanism is provided with an elastic member that biases the tip in a direction that grips an object. The aforementioned fixed finger, An opposing portion provided on the tip side so as to face the aforementioned tip portion, A support portion is provided between the opposing portion and the first base portion, In a plan view perpendicular to the axis of rotation between the base and the tip, The opposing portion is formed along the linear motion direction of the first linear motion mechanism, The gripping mechanism according to claim 1, wherein the support portion is formed to widen toward the tip.
  3. The gripping mechanism according to claim 2, wherein the fixed finger and the movable finger enclose and grip the object, with the opposing portion and the support portion of the fixed finger in contact with the object, and the tip portion and the base portion of the movable finger in contact with the object.
  4. The gripping mechanism according to any one of claims 1 to 3, wherein the fixed finger is provided with a proximity sensor for detecting when it is close to an object.
  5. A gripping method for gripping an object using the gripping mechanism described in claim 1, comprising the steps of determining a contact point on the surface of the object based on a depth image or point cloud data of the object, A step of changing the position and orientation of the gripping mechanism based on the contact point, A gripping method comprising the steps of: operating the first linear motion mechanism and the second linear motion mechanism while the fixed finger is in contact with the contact point of the object to grip the object.

Description

This disclosure relates to a gripping mechanism and a gripping method. Patent Document 1 discloses a gripping mechanism that uses two gripping pieces to grip an object. International Publication No. 2017/195246 This diagram shows the configuration of a robot hand.This diagram shows the configuration of a robot hand.This diagram shows the configuration of a robot hand.This diagram shows the configuration of a robot hand.This is a schematic diagram showing the configuration of a gripping system with a robotic hand.This is a flowchart showing the learning method. The following description of this embodiment will be based on the drawings. However, the present invention is not limited to the following embodiments. Furthermore, for clarity, the following description and drawings have been simplified as appropriate. The configuration and operation of the robot hand 100 according to this embodiment will be explained using Figures 1 to 4. Figures 1 to 4 show the configuration of the robot hand 100, which is a gripping mechanism. The robot hand 100 comprises a fixed finger 10, a first base portion 11, a movable finger 20, a second base portion 21, a link mechanism 30, a first linear motion mechanism 40, and a second linear motion mechanism 50. The robot hand 100 is a sub-acting hand with fewer actuators than degrees of freedom. As described later, the robot hand 100 is attached to an arm mechanism. Therefore, the arm mechanism drives the robot hand 100 to a position and orientation that allows it to grasp object O. The robot hand 100 power grasps object O by gripping it with its fixed fingers 10 and movable fingers 20. The robot hand 100 acts as an end effector for grasping object O. In Figures 1 and 3, the object O to be grasped is a cylindrical bottle, but this is not particularly limited. Figures 1 and 2 show the fixed fingers 10 and movable fingers 20 in the open position. Specifically, Figure 1 shows the configuration at the time when the robot hand 100 begins the grasping operation of object O. Figure 2 shows the same configuration as in Figure 1, but without object O. Figures 3 and 4 show the fixed fingers 10 and movable fingers 20 in the closed position. Figure 3 shows the state in which object O is being grasped. Figure 4 shows the state without object O. As will be described later, the robot hand 100 opens and closes as the movable fingers 20 rotate relative to the fixed fingers 10. Figures 1 to 4 use a three-dimensional Cartesian coordinate system (XYZ). Here, the X direction is parallel to the linear motion direction of the first linear motion mechanism 40, which will be described later. The +X direction is the direction in which the robot hand 100 approaches the object. The Z direction is parallel to the rotation axes 26, 27, 37, and 38, which will be described later. For the sake of simplicity, the XY plane is assumed to be the horizontal plane. Therefore, the object O to be grasped is assumed to be placed on a table parallel to the XY plane. The Z direction is the vertical direction, parallel to the axial direction of the cylindrical object O. Of course, the XY plane may be a plane other than the horizontal plane, and the Z axis may be in a different direction from the vertical. The X, Y, and Z directions change depending on the position and orientation of the robot hand 100 grasping the object O. When the robot hand 100 grasps an object O, the first linear motion mechanism 40 and the second linear motion mechanism 50 operate in conjunction. Specifically, when the robot hand 100 grasps an object O, the first linear motion mechanism 40 and the second linear motion mechanism 50 drive the movable finger 20 toward the fixed finger 10. In other words, the movable finger 20 moves in the direction indicated by the arrows in Figures 1 and 2. Then, as shown in Figure 3, the fixed finger 10 and the movable finger 20 grip the object O. Conversely, when the robot hand 100 releases an object, the first linear motion mechanism 40 and the second linear motion mechanism 50 drive the movable finger 20 away from the fixed finger 10. In other words, the movable finger 20 moves in the opposite direction to the direction indicated by the arrows in Figures 1 and 2. Here, the direction of the arrows in Figures 1 and 2 is defined as the approaching direction, and the direction opposite to the arrows is defined as the moving-away direction. Furthermore, the space between the fixed finger 10 and the movable finger 20 is defined as the gripping space S. The movable finger 20 is positioned opposite the fixed finger 10, with the gripping space S in between. As the movable finger 20 moves in the approaching direction, the gripping space S narrows. Then, the fixed finger 10 and the movable finger 20 enclose and grasp the object O placed in the gripping space S. The fixed finger 10 is fixed to the first base portion 11. The movable finger 20 is attached to the second base portion 21. The first base portion 11 holds the first linear m