Approach sense and touch sense collaborative mechanical gripper sensing system for self-adaptive grabbing

Abstract

The invention provides a proximity sense and touch sense collaborative mechanical gripper sensing system for self-adaptive grabbing, and belongs to the technical field of robot sensing. The proximity sense and touch sense collaborative mechanical gripper sensing system comprises a sensing module, an execution module and a data transmission and processing module; the sensing module comprises a flexible transparent fingertip, a proximity sensor array and a multiplexer; the execution module comprises a three-finger manipulator and a mechanical arm; the data transmission and processing module comprises a controller and an upper computer. Compared with a traditional proximity sense-touch sense grabbing perception scheme, a proximity sense-touch sense collaborative perception framework with space consistency is established, information alignment errors are effectively reduced, the time-space consistency and fusion efficiency of perception are remarkably improved, the multi-dimensional characteristics of a target object can be represented more comprehensively, and the method has the advantages of being high in robustness, high in robustness and the like. And the grabbing posture and force are adjusted in a self-adaptive mode, and high-precision and high-robustness grabbing in the dynamic environment is achieved. In addition, soft grabbing is achieved through the flexible fingers, object damage is avoided, and the grabbing efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of robot sensing technology, and in particular to a proximity sense and tactile sense coordinated mechanical gripper sensing system for adaptive grasping. Background Art

[0002] In recent years, active sensing technology for manipulators has been widely used in complex manipulation tasks. As a mainstream method, visual-tactile joint perception combines the long-range information capture capability of vision with the fine contact information perception capability of touch, which improves the adaptive grasping performance of manipulator grippers to a certain extent. However, visual perception is easily disturbed by illumination changes, occlusions, and background complexity in complex scenes, and it is difficult to provide stable and reliable prior information. In contrast, the combination of proximity and tactile perception shows significant technical advantages, which can not only perform non-contact perception, but also effectively avoid occlusion problems. However, the current sensing schemes are mostly spatially separated in proximity and tactile perception, which leads to the problem of time and space mismatch when the information of the two modalities is fused, and the computational complexity is high, which makes it difficult to meet the requirements of efficient operation in dynamic environments, so the performance of the grasping system is greatly limited. In addition, many existing grasping systems rely on rigid fingers, which face challenges when handling fragile, flexible, or irregularly shaped objects, and cannot effectively avoid damage to the objects. Summary of the invention

[0003] The embodiments of the present invention provide a robotic gripper sensing system with coordinated proximity and tactile senses for adaptive grasping, which solves the problem that in traditional proximity-tactile grasping sensing schemes, proximity and tactile senses are spatially separated, resulting in temporal and spatial mismatches and high computational complexity when the information of the two modalities is fused, and solves the problem that rigid fingers are prone to damage to objects when handling fragile, flexible or irregularly shaped objects.

[0004] On the one hand, an embodiment of the present invention provides a proximity and tactile coordinated robotic gripper perception system for adaptive grasping, including a perception module, an execution module, and a data transmission and processing module; The sensing module includes a flexible transparent fingertip, a proximity sensor array, and a multiplexer; The execution module includes a three-finger manipulator and a robotic arm; The data transmission and processing module includes a controller and a host computer; The flexible transparent fingertips are made of highly elastic and ductile PETG material, prepared by 3D printing, imitating human fingers to achieve soft grasping of objects; The proximity sensor array is composed of three proximity sensors, which are arranged in an equilateral triangle on the PCB board, and the multiplexer is placed in the middle of the equilateral triangle array; The proximity sensor array feeds back proximity information and tactile information, which are spatially consistent and are used for adaptive adjustment of the gripping posture and strength of the manipulator; The proximity sensor array is tightly embedded in the flexible transparent fingertip, worn on the three-fingered mechanical finger, and communicates with the controller using the IIC protocol; The controller is connected to the host computer.

[0005] Preferably, the proximity sensor adopts a highly integrated infrared proximity sensor chip.

[0006] Preferably, the data transmission and processing module uses UART communication protocol to realize communication between the controller and the host computer, and uses UART communication protocol to realize communication between the controller and the execution module.

[0007] On the other hand, an embodiment of the present invention further provides a working method of a proximity and tactile coordinated manipulator gripper sensing system for adaptive grasping as described in the above embodiment, and the working method mainly comprises the following steps: S1: System initialization; S2: Acquisition of proximity information and adaptive adjustment of grasping posture; S3: tactile information collection and adaptive adjustment of grasping force; S4: Grasp the target object.

[0008] Preferably, S2 comprises the following steps: S2.1: Collect the raw values ​​of 9 proximity sensors in three proximity sensor arrays ,in , represents the group number of the proximity sensor array, , represents the number of the proximity sensor; the host computer uses the pre-trained neural network model to Converted to the distance to the surface of the target object ; S2.2: Calculate the rolling angles of the three groups of flexible transparent fingertips respectively and pitch angle , calculate the closest distance between three sets of flexible transparent fingertips The calculation formula is as follows: , , , in, It is The rolling angle of the flexible transparent fingertips, It is The pitch angle of the flexible transparent fingertips, They are The distance from the three proximity sensors of the flexible transparent fingertips to the surface of the target object, is the side length of the equilateral triangle proximity sensor array, It is The shortest distance between the sensor array of a flexible transparent fingertip and the surface of the target object; S2.3: , With the goal in mind, the grasping posture of the three-finger manipulator is adjusted in time through error feedback control, so that the target object is basically located in the middle of the three fingers, and the contact surfaces of the three fingers and the target object are basically parallel.

[0009] Preferably, S3 is specifically: When the robotic arm equipped with flexible transparent fingertips touches the surface of the target object, the proximity sensor array indirectly reflects the tactile information, which is transmitted to the host computer for sorting and analysis, and the grasping force is controlled within an appropriate range.

[0010] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages: (1) The present invention designs a proximity and tactile collaborative robotic gripper sensing system for adaptive grasping. By embedding a proximity sensor array into a flexible transparent fingertip, a proximity-tactile collaborative sensing framework with spatial consistency is established. Before and after contacting the target object, proximity and tactile data can be collected at the same spatial position, effectively reducing information alignment errors, significantly improving the spatiotemporal consistency and fusion efficiency of perception, and more comprehensively characterizing the multi-dimensional characteristics of the target object. Based on this, the grasping posture and strength can be adaptively adjusted to achieve high-precision and high-robust grasping in a dynamic environment.

[0011] (2) The proximity sensor array designed for this system is arranged in an equilateral triangle. The positions of the three proximity sensors are relatively fixed and concise, which simplifies the calculation process of information processing and improves the real-time and efficiency of robot perception.

[0012] (3) The system uses PETG material to make flexible transparent fingertips with high elasticity and high ductility, simulating human fingers to achieve soft grasping, effectively improving grasping flexibility, reducing damage, and enhancing the adaptability of the grasping process. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The overall structure diagram of a proximity and tactile coordinated robotic gripper sensing system for adaptive grasping provided in one embodiment of the present invention; Figure 2A structural diagram of a perception module of a proximity and tactile collaborative robotic gripper perception system for adaptive grasping provided in one embodiment of the present invention; Figure 3 It is a flow chart of a working method of a proximity and tactile coordinated manipulator gripper sensing system for adaptive grasping provided in one embodiment of the present invention; In the figure: 1. Flexible transparent fingertips; 2. Proximity sensor array; 3. Multiplexer; 4. Three-finger manipulator; 5. Robotic arm; 6. Controller; 7. Host computer. DETAILED DESCRIPTION

[0014] The embodiments of the present invention provide a robotic gripper sensing system with coordinated proximity and tactile senses for adaptive grasping, which solves the problem that in traditional proximity-tactile grasping sensing schemes, proximity and tactile senses are spatially separated, resulting in temporal and spatial mismatches and high computational complexity when the information of the two modalities is fused, and solves the problem that rigid fingers are prone to damage to objects when handling fragile, flexible or irregularly shaped objects.

[0015] In order to more clearly illustrate the purpose, technical solution and advantages of the present invention, the present invention will be described in detail in conjunction with specific embodiments and drawings. It should be noted that the embodiments and descriptions described herein are only illustrative contents and do not limit the present invention in any form.

[0016] like Figure 1-Figure 3 As shown, the present invention provides a proximity and tactile coordinated robotic gripper sensing system for adaptive grasping, including a sensing module, an execution module, and a data transmission and processing module; The sensing module includes a flexible transparent fingertip 1, a proximity sensor array 2, and a multiplexer 3; The execution module includes a three-finger manipulator 4 and a manipulator arm 5; The data transmission and processing module includes a controller 6 and a host computer 7; The flexible transparent fingertip 1 is made of highly elastic and ductile PETG (polyethylene terephthalate glycol) material, prepared by 3D printing, imitating human fingers to achieve soft grasping of objects; The proximity sensor array 2 is composed of three proximity sensors, which are arranged in an equilateral triangle on the PCB board, and the multiplexer 3 is placed in the middle of the equilateral triangle array; The proximity sensor array 2 feeds back proximity information and tactile information, which are spatially consistent and are used for adaptive adjustment of the gripping posture and strength of the manipulator 2; The proximity sensor array 2 is tightly embedded in the flexible transparent fingertip 1, worn on the fingers of the three-finger manipulator 4, and communicates with the controller 6 using the IIC protocol; The controller 6 is connected to the host computer 7 .

[0017] Preferably, the proximity sensor 2 adopts a highly integrated infrared proximity sensor chip; Preferably, the data transmission and processing module uses the UART communication protocol to realize the communication between the controller 6 and the host computer 7, and uses the UART communication protocol to realize the communication between the controller 6 and the execution module.

[0018] The embodiment of the present invention further provides a working method of the proximity and tactile coordinated manipulator gripper sensing system for adaptive grasping as described in the above embodiment, comprising the following steps: S1: System initialization; S2: Acquisition of proximity information and adaptive adjustment of grasping posture; S3: tactile information collection and adaptive adjustment of grasping force; S4: Grasp the target object.

[0019] Preferably, S2 comprises the following steps: S2.1: Collect the raw values ​​of the nine proximity sensors of the three proximity sensor arrays 2 ,in , represents the group number of proximity sensor array 2, , represents the number of the proximity sensor; the host computer 7 uses the pre-trained neural network model to Converted to the distance to the surface of the target object ; S2.2: Calculate the rolling angles of the three groups of flexible transparent fingertips 1 respectively and pitch angle , calculate the closest distance between the three groups of flexible transparent fingertips 1, the calculation formula is as follows: , , , in, It is The rolling angle of the flexible transparent fingertips, It is The pitch angle of the flexible transparent fingertips, ( ) are respectively The distance from the three proximity sensors of the flexible transparent fingertips to the surface of the target object, is the side length of the equilateral triangle proximity sensor array, It is The shortest distance between the sensor array of a flexible transparent fingertip and the surface of the target object; S2.3: , For the goal, through error feedback control, the grasping posture of the three-finger manipulator 4 is timely adjusted so that the contact surface of the three fingers and the target object is basically parallel, and the target object is basically located in the middle of the three fingers, which can prevent the target object from being pushed down while improving the grasping stability.

[0020] Preferably, S3 is specifically as follows: when the manipulator 2 equipped with the flexible transparent fingertip 1 contacts the surface of the target object, the proximity sensor array 2 indirectly reflects the tactile information, which is transmitted to the host computer 7 for sorting and analysis, so as to control the grasping force within an appropriate range.

[0021] The present invention designs a proximity and tactile collaborative robotic gripper sensing system for adaptive grasping. By embedding the proximity sensor array into the flexible transparent fingertips, a proximity-tactile collaborative sensing framework with spatial consistency is established. Before and after contacting the target object, proximity and tactile data can be collected at the same spatial position, effectively reducing the information alignment error, significantly improving the spatiotemporal consistency and fusion efficiency of perception, and being able to more comprehensively characterize the multi-dimensional characteristics of the target object, and adaptively adjust the grasping posture and strength accordingly, to achieve high-precision and high-robust grasping in a dynamic environment.

[0022] The proximity sensor array designed for this system is arranged in an equilateral triangle. The positions of the three proximity sensors are relatively fixed and simple, which simplifies the calculation process of information processing and improves the real-time performance of the robot's perception.

[0023] The system uses PETG material to make flexible and transparent fingertips with high elasticity and ductility, simulating human fingers to achieve soft grasping, effectively improving grasping flexibility, reducing damage, and enhancing the adaptability of the grasping process.

[0024] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A robot gripper sensing system with proximity and tactile synergy for adaptive grasping, characterized in that: It includes a perception module, an execution module and a data transmission and processing module; The sensing module includes a flexible transparent fingertip, a proximity sensor array, and a multiplexer; The execution module includes a three-finger manipulator and a robotic arm; The data transmission and processing module includes a controller and a host computer; The flexible transparent fingertips are made of highly elastic and ductile PETG material, prepared by 3D printing, imitating human fingers to achieve soft grasping of objects; The proximity sensor array is composed of three proximity sensors, which are arranged in an equilateral triangle on the PCB board, and the multiplexer is placed in the middle of the equilateral triangle array; The proximity sensor array feeds back proximity information and tactile information, which are spatially consistent and are used for adaptive adjustment of the gripping posture and strength of the manipulator; The proximity sensor array is tightly embedded in the flexible transparent fingertip, worn on the three-fingered mechanical finger, and communicates with the controller using the IIC protocol; The controller is connected to the host computer.

2. The proximity and tactile synergistic robotic gripper sensing system for adaptive grasping as claimed in claim 1, characterized in that: The proximity sensor adopts a highly integrated infrared proximity sensor chip.

3. The proximity and tactile synergistic robotic gripper sensing system for adaptive grasping according to claim 1, characterized in that: The data transmission and processing module uses the UART communication protocol to realize the communication between the controller and the host computer, and uses the UART communication protocol to realize the communication between the controller and the execution module.

4. A working method of a proximity and tactile coordinated manipulator gripper sensing system for adaptive grasping as claimed in claims 1 to 3, the working method mainly comprising the following steps: S1: System initialization; S2: Acquisition of proximity information and adaptive adjustment of grasping posture; S3: tactile information collection and adaptive adjustment of grasping force; S4: Grasp the target object.

5. The working method according to claim 4, characterized in that: The S2 comprises the following steps: S2.1: Collect the raw values ​​of 9 proximity sensors in three proximity sensor arrays ,in , represents the group number of the proximity sensor array, , represents the number of the proximity sensor; the host computer uses the pre-trained neural network model to Converted to the distance to the surface of the target object ; S2.2: Calculate the rolling angles of the three groups of flexible transparent fingertips respectively and pitch angle , calculate the shortest distance between the three groups of flexible transparent fingertips, the calculation formula is as follows: ， ， ， in, It is The rolling angle of the flexible transparent fingertips, It is The pitch angle of the flexible transparent fingertips, They are The distance from the three proximity sensors of the flexible transparent fingertips to the surface of the target object, is the side length of the equilateral triangle proximity sensor array, It is The shortest distance between the sensor array of a flexible transparent fingertip and the surface of the target object; S2.3: , With the goal in mind, the grasping posture of the three-finger manipulator is adjusted in time through error feedback control, so that the target object is basically located in the middle of the three fingers, and the contact surfaces of the three fingers and the target object are basically parallel.

6. The working method according to claim 4, characterized in that: The S3 is specifically: When the robotic arm equipped with flexible transparent fingertips touches the surface of the target object, the proximity sensor array indirectly reflects the tactile information, which is transmitted to the host computer for sorting and analysis, and the grasping force is controlled within an appropriate range.

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