Intelligent Robot Hand Research Articles

A Skin-Inspired High-Performance Tactile Sensor for Accurate Recognition of Object Softness.

High-performance tactile sensors with skin-sensing properties are crucial for intelligent perception in next-generation smart devices. However, previous studies have mainly focused on the sensitivity and response range of tactile sensation while neglecting the ability to recognize object softness. Therefore, achieving a precise perception of the softness remains a challenge. Here, we report an integrated tactile sensor consisting of a central hole gradient structure pressure sensor and a planar structure strain sensor. The recognition of softness and tactile perception is achieved through the synergistic effect of pressure sensors that sense the applied pressure and strain sensors that recognize the strain of the target object. The results indicate that the softness evaluation parameter (SC) of the integrated structural tactile sensor increases from 0.14 to 0.47 along with Young's modulus of the object decreasing from 2.74 to 0.45 MPa, demonstrating accurate softness recognition. It also exhibits a high sensitivity of 10.55 kPa-1 and an ultrawide linear range of 0-1000 kPa, showing an excellent tactile sensing capability. Further, an intelligent robotic hand system based on integrated structural tactile sensors was developed, which can identify the softness of soft foam and glass and grasp them accurately, indicating human skin-like sensing and grasping capabilities.

Ultraflexible Temperature-Strain Dual-Sensor Based on Chalcogenide Glass-Polymer Film for Human-Machine Interaction.

Skin-like thermoelectric (TE) films with temperature- and strain-sensing functions are highly desirable for human-machine interaction systems and wearable devices. However, current TE films still face challenges in achieving high flexibility and excellent sensing performance simultaneously. Herein, for the first time, a facile roll-to-roll strategy is proposed to fabricate an ultraflexible chalcogenide glass-polytetrafluoroethylene composite film with superior temperature- and strain-sensing performance. The unique reticular network of the composite film endows it with efficient Seebeck effect and flexibility, leading to a high Seebeck coefficient (731 µV/K), rapid temperature response (≈0.7 s), and excellent strain sensitivity (gauge factor = 836). Based on this high-performance composite film, an intelligent robotic hand for action feedback and temperature alarm is fabricated, demonstrating its great potential in human-machine interaction. Such TE film fabrication strategy not only brings new inspiration for wearable inorganic TE devices, but also sets the stage for a wide implementation of multifunctional human-machine interaction systems.

Hygrothermic Wood Actuated Robotic Hand.

Stimulus-responsive actuators play a vital role in the new generation of intelligent systems. However, poor mechanical performance, complicated fabrication processes, and the inability to complex deformation limit their practical applications. Herein, these challenges are overcome via designing a strong hygrothermic wood actuator with asymmetric water affinity. The actuator is readily constructed by sandwiching polypyrrole-coated wood with a Ni complex hygroscopic gel top layer for moisture absorption and a polyimide bottom layer as the water barrier. The resulting hygrothermic wood spontaneously stretches and bends itself in response to moisture and thermal/light stimulation. A robotic hand and a series of grippers made of hygrothermic wood demonstrate dexterous object-hand interactions during grasping and holding, while the reversible hygrothermic property allows the actuator to be potentially applied in fire rescue scenarios to rescue trapped objects. A combination of good mechanical properties, multi-stimulus-response, complex deformation, wide working temperature range, low manufacturing cost, and biocompatibility are simultaneously realized by one device. It is thus believed that such a strong wood actuator will open up a new avenue for building intelligent robotic hand systems.

Development of flexible tactile sensor for the envelop of curved robotic hand finger in grasping force sensing

Intelligent robotic hand with integrated tactile sensor is able to perform real-time tactile information sensing, which is crucial for dexterous grasping and manipulation. This paper presents a novel flexible tactile sensor with 18 sensing units to envelop a complex-shaped robotic hand finger for grasping force measurement. A new approach based on point cloud fitting and triangular searching is developed to determine the special configuration of these 18 sensing units on the complex finger surface, and it is used for the structural design of the flexible tactile sensor. The fabrication process to make the tactile sensor is developed and fabricated tactile sensor features high flexibility and can be perfectly enveloped around robotic hand finger. Calibration results show that the sensor has relatively high sensitivities for three-axis force sensing: 1.87 V/N at 0.1 ~ 0.7 N and 0.47 V/N at 0.7 ~ 3 N for z-axis normal force sensing, 1.59 V/N and 1.49 V/N at −1 ~ 1 N for x- and y-axes shear force sensing, respectively. Besides, the tactile sensor has good reproducibility and generally low cross-talk interferences between the sensing units. After being wrapped onto robotic hand finger, this sensor is utilized to measure the distributed contact forces when the robotic hand grasps different objects. The effects of grasping movements on the generated contact forces are analyzed. The obtained results demonstrate that the developed tactile sensor has great potentials for the perception of tactile information in human-robotic interactions.

ロボットハンドの知能化を目的とした階層的情報処理を行う近接覚センサシステムの開発

ロボットハンドの知能化を目的とした階層的情報処理を行う近接覚センサシステムの開発

Intelligent Computational Control of Multi-Fingered Dexterous Robotic Hand

We discuss the intelligent computational control theory and introduce the hardware structure of HIT/DLR II dexterous robotic hand, which is the typical dexterous robotic hand. We show that how DSP or FPGA controller can be used in the dexterous robotic hand. A popular intelligent dexterous robotic hand control system, which named Electromyography (EMG) control is investigated. We introduced some mathematical algorithms in EMG controlling, such as Gauss mixture model (GMM), artificial neural network (ANN) and Support vector machine (SVM).

지능형 로봇손을 위한 손가락 힘센서 개발

This paper describes a design and manufacture of a two-axis force sensor and a single-axis force sensor for the fingers of an intelligent robot's hand. The robot's finger is composed of a two-axis force sensor, a first knuckle, a single-axis force sensor, a second knuckle, a spring, a motor of first knuckle, a motor of second knuckle, and so on. The two-axis force sensor attached to the first knuckle and the single-axis force sensor attached to the second knuckle were designed and manufactured, and the characteristics test of two sensors was carried out. As a test results, the interference error of the two-axis force sensor was less than 0.68%, the repeatability error of each sensor was less than 0.02%, and then the non-linearity was less than 0.03%. It is thought that the sensors can be used for the fingers of the intelligent robot's hand for rehabilitation exercise of finger patients.

Design and Application of an Intelligent Robotic Gripper for Accurate and Tolerant Electronic Connector Mating

In electronic manufacturing systems, the design of the robotic hand is important for successful accomplishment of the assembly task, and also for human and robot coworker coordinated assembly. Due to the restrictions on the architecture of traditional robotic hands, the status of assembly parts, such as position and rotation during the assembly process cannot be detected effectively. In this research, an intelligent robotic hand – i-Hand, equipped with multiple small sensors – is designed and built for this purpose. Mating connectors by robot, as an experimental case in this paper, is studied to evaluate i-Hand performance. A new model that converts the traditional time-zone-driven model to an event-driven model is proposed to describe the process ofmating connectors, within which, most importantly, the distance between the connector and deformable Printed Circuit Board (PCB) is detected by i-Hand. The generated curve has provided more robust parameters than our previously studied Fault Detection and Diagnosis (FDD) classifier. Various possible situations during assembly are considered and handled based on this event-driven work flow. The effectiveness of our proposed model and algorithm is proven in experiments.

Research of a Kind of New Intelligent Robot Hand Material

In order to further enhancing the ratio of load of the current intelligent industrial robot to its weight, and making the structure and movement of the intelligent robot develop rapidly toward the modularization, flexibility and reconfigurable mode, a kind of new-type intelligent robot hand material with high strength, light mass and large damping is proposed in the paper. The new composition material and its performance are also introduced and discussed in detail. Based on it, the specific preparation method and technology of the new-type composite material are given. The experimental results show that the weight of the intelligent robot hand material proposed in the paper can reduce by about 30% under the premise of ensuring the good strength of the intelligent robot hand.

Development of Intelligent Robot Hand Using Proximity, Contact and Slip Sensing

Development of Intelligent Robot Hand Using Proximity, Contact and Slip Sensing

3축 손가락 힘센서를 가진 지능로봇의 지능형 로봇손 개발

This paper describes the intelligent robot's hand with three-axis finger force sensors for an intelligent robot. In order to grasp an unknown object safely, it should measure the mass of the object, and determine the grasping force using the mass, then control the robot's fingers with the grasping force. In this paper, the intelligent robot's hand for an intelligent robot was developed. First, the three-axis finger force sensors were designed and manufactured, second, the intelligent robot's hand with three-axis finger force sensors were designed and fabricated, third, the high-speed control system was designed and manufactured using DSP( digital signal processor), finally, the characteristic test to grasp an unknown object safely was carried out. It was confirmed that the developed intelligent robot's hand could grasp an unknown object safely.

2A2-J04 インテリジェントロボットハンドの研究開発 : Pick and Placeの達成

To achieve a skillful operation like the human being by robot hand, an interaction with the vision and the tactile sense is indispensable. To consider the safe and certain grasping operation by the robot hand, we proposed use of proximity sensor which can detect the several tens of millimeters from finger-tip surface and tactile sensor. And we call such a robot hand an "intelligent robot hand" and develop this. This time, we propose the control method of internal force based on CoP(center of pressure) tactile sensor for the achievement of grasping by three fingers and confirmed utility of the proposal method by the experiments.