Tactile Sensors for Parallel Grippers: Design and Characterization

Tactile data perception is of paramount importance in today’s robotics applications. This paper describes the latest design of the tactile sensor developed in our laboratory. Both the hardware and firmware concepts are reported in detail in order to allow the research community the sensor reproduction, also according to their needs. The sensor is based on optoelectronic technology and the pad shape can be adapted to various robotics applications. A flat surface, as the one proposed in this paper, can be well exploited if the object sizes are smaller than the pad and/or the shape recognition is needed, while a domed pad can be used to manipulate bigger objects. Compared to the previous version, the novel tactile sensor has a larger sensing area and a more robust electronic, mechanical and software design that yields less noise and higher flexibility. The proposed design exploits standard PCB manufacturing processes and advanced but now commercial 3D printing processes for the realization of all components. A GitHub repository has been prepared with all files needed to allow the reproduction of the sensor for the interested reader. The whole sensor has been tested with a maximum load equal to 15N, by showing a sensitivity equal to 0.018V/N. Moreover, a complete and detailed characterization for the single taxel and the whole pad is reported to show the potentialities of the sensor also in terms of response time, repeatability, hysteresis and signal to noise ratio.

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A hybrid tactile sensor-based obstacle overcoming method for hexapod walking robots

Intelligent Service Robotics ◽

10.1007/s11370-020-00340-9 ◽

2020 ◽

Author(s):

Mindaugas Luneckas ◽

Tomas Luneckas ◽

Dainius Udris ◽

Darius Plonis ◽

Rytis Maskeliūnas ◽

...

Keyword(s):

Degrees Of Freedom ◽

Flat Surface ◽

Tactile Sensor ◽

Legged Robots ◽

Walking Robots ◽

Positional Error ◽

Tactile Sensors ◽

Robot Locomotion ◽

Promising Solution ◽

Novel Method

AbstractWalking robots are considered as a promising solution for locomotion across irregular or rough terrain. While wheeled or tracked robots require flat surface like roads or driveways, walking robots can adapt to almost any terrain type. However, overcoming diverse terrain obstacles still remains a challenging task even for multi-legged robots with a high number of degrees of freedom. Here, we present a novel method for obstacle overcoming for walking robots based on the use of tactile sensors and generative recurrent neural network for positional error prediction. By using tactile sensors positioned on the front side of the legs, we demonstrate that a robot is able to successfully overcome obstacles close to robots height in the terrains of different complexity. The proposed method can be used by any type of a legged machine and can be considered as a step toward more advanced walking robot locomotion in unstructured terrain and uncertain environment.

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Blocks World of Touch: Exploiting the Advantages of All-Around Finger Sensing in Robot Grasping

Frontiers in Robotics and AI ◽

10.3389/frobt.2020.541661 ◽

2020 ◽

Vol 7 ◽

Author(s):

Daniel Fernandes Gomes ◽

Zhonglin Lin ◽

Shan Luo

Keyword(s):

Tactile Sensor ◽

The Novel ◽

Tactile Sensors ◽

Reach To Grasp ◽

Cluttered Environments ◽

Remote Sensors ◽

Robot Grasping ◽

Limited Sensing ◽

Human Finger ◽

Blocks World

Tactile sensing is an essential capability for a robot to perform manipulation tasks in cluttered environments. While larger areas can be assessed instantly with cameras, Lidars, and other remote sensors, tactile sensors can reduce their measurement uncertainties and gain information of the physical interactions between the objects and the robot end-effector that is not accessible via remote sensors. In this paper, we introduce the novel tactile sensor GelTip that has the shape of a finger and can sense contacts on any location of its surface. This contrasts to other camera-based tactile sensors that either only have a flat sensing surface, or a compliant tip of a limited sensing area, and our proposed GelTip sensor is able to detect contacts from all the directions, like a human finger. The sensor uses a camera located at its base to track the deformations of the opaque elastomer that covers its hollow, rigid, and transparent body. Because of this design, a gripper equipped with GelTip sensors is capable of simultaneously monitoring contacts happening inside and outside its grasp closure. Our extensive experiments show that the GelTip sensor can effectively localize these contacts at different locations of the finger body, with a small localization error of approximately 5 mm on average, and under 1 mm in the best cases. Furthermore, our experiments in a Blocks World environment demonstrate the advantages, and possibly a necessity, of leveraging all-around touch sensing in manipulation tasks. In particular, the experiments show that the contacts at different moments of the reach-to-grasp movements can be sensed using our novel GelTip sensor.

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Elementy poetyki ludowej w powieści Rzeczy uprzyjemniające. Utopia T. Bołdak-Janowskiej

10.31338/2544-3135.si.2020-13.9 ◽

2020 ◽

pp. 182-197

Author(s):

Agnieszka Goral

Keyword(s):

Fairy Tales ◽

Text Analysis ◽

Literary Text ◽

Source Material ◽

Human Existence ◽

The Other ◽

The Novel ◽

Literary Works ◽

The One ◽

Cultural Features

The aim of the article is to analyse the elements of folk poetics in the novel Pleasant things. Utopia by T. Bołdak-Janowska. The category of folklore is understood in a rather narrow way, and at the same time it is most often used in critical and literary works as meaning a set of cultural features (customs and rituals, beliefs and rituals, symbols, beliefs and stereotypes) whose carrier is the rural folk. The analysis covers such elements of the work as place, plot, heroes, folk system of values, folk rituals, customs, and symbols. The description is conducted based on the analysis of source material as well as selected works in the field of literary text analysis and ethnolinguistics. The analysis shows that folk poetics was creatively associated with the elements of fairy tales and fantasy in the studied work, and its role consists of – on the one hand – presenting the folk world represented and – on the other – presenting a message about the meaning of human existence.

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Application of Novel Low Current OBIRCH Amplifier and Nanoprobing to Identify Subtle Leakages in Advanced Node Technologies

10.31399/asm.cp.istfa2018p0303 ◽

2018 ◽

Author(s):

Satish Kodali ◽

Liangshan Chen ◽

Yuting Wei ◽

Tanya Schaeffer ◽

Chong Khiam Oh

Keyword(s):

Signal To Noise Ratio ◽

Semiconductor Industry ◽

Fault Isolation ◽

Ring Oscillator ◽

High Signal ◽

The Novel ◽

Resistance Change ◽

Three Samples ◽

Relative Threshold ◽

First Time

Abstract Optical beam induced resistance change (OBIRCH) is a very well-adapted technique for static fault isolation in the semiconductor industry. Novel low current OBIRCH amplifier is used to facilitate safe test condition requirements for advanced nodes. This paper shows the differences between the earlier and novel generation OBIRCH amplifiers. Ring oscillator high standby leakage samples are analyzed using the novel generation amplifier. High signal to noise ratio at applied low bias and current levels on device under test are shown on various samples. Further, a metric to demonstrate the SNR to device performance is also discussed. OBIRCH analysis is performed on all the three samples for nanoprobing of, and physical characterization on, the leakage. The resulting spots were calibrated and classified. It is noted that the calibration metric can be successfully used for the first time to estimate the relative threshold voltage of individual transistors in advanced process nodes.

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Dombey and Son

10.1093/owc/9780199536283.001.0001 ◽

2008 ◽

Author(s):

Charles Dickens ◽

Dennis Walder

Keyword(s):

Family Relationships ◽

The Sun ◽

The Novel ◽

The Earth ◽

The Future ◽

Original Illustrations ◽

The One

Dombey and Son ... Those three words conveyed the one idea of Mr. Dombey's life. The earth was made for Dombey and Son to trade in, and the sun and moon were made to give them light.' The hopes of Mr Dombey for the future of his shipping firm are centred on his delicate son Paul, and Florence, his devoted daughter, is unloved and neglected. When the firm faces ruin, and Dombey's second marriage ends in disaster, only Florence has the strength and humanity to save her father from desolate solitude. This new edition contains Dickens's prefaces, his working plans, and all the original illustrations by ‘Phiz’. The text is that of the definitive Clarendon edition. It has been supplemented by a wide-ranging Introduction, highlighting Dickens's engagement with his times, and the touching exploration of family relationships which give the novel added depth and relevance.

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A Vibrissa-Inspired Highly Flexible Tactile Sensor: Scanning 3D Object Surfaces Providing Tactile Images

Sensors ◽

10.3390/s21051572 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1572

Author(s):

Lukas Merker ◽

Joachim Steigenberger ◽

Rafael Marangoni ◽

Carsten Behn

Keyword(s):

Steel Wire ◽

Sense Organ ◽

Tactile Sensor ◽

Tactile Sensors ◽

Measuring Device ◽

3D Object ◽

Torque Transducer ◽

Sense Of Touch ◽

Important Basis ◽

Support Reactions

Just as the sense of touch complements vision in various species, several robots could benefit from advanced tactile sensors, in particular when operating under poor visibility. A prominent tactile sense organ, frequently serving as a natural paragon for developing tactile sensors, is the vibrissae of, e.g., rats. Within this study, we present a vibrissa-inspired sensor concept for 3D object scanning and reconstruction to be exemplarily used in mobile robots. The setup consists of a highly flexible rod attached to a 3D force-torque transducer (measuring device). The scanning process is realized by translationally shifting the base of the rod relative to the object. Consequently, the rod sweeps over the object’s surface, undergoing large bending deflections. Then, the support reactions at the base of the rod are evaluated for contact localization. Presenting a method of theoretically generating these support reactions, we provide an important basis for future parameter studies. During scanning, lateral slip of the rod is not actively prevented, in contrast to literature. In this way, we demonstrate the suitability of the sensor for passively dragging it on a mobile robot. Experimental scanning sweeps using an artificial vibrissa (steel wire) of length 50 mm and a glass sphere as a test object with a diameter of 60 mm verify the theoretical results and serve as a proof of concept.

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Soft magnetic skin for super-resolution tactile sensing with force self-decoupling

Science Robotics ◽

10.1126/scirobotics.abc8801 ◽

2021 ◽

Vol 6 (51) ◽

pp. eabc8801

Author(s):

Youcan Yan ◽

Zhe Hu ◽

Zhengbao Yang ◽

Wenzhen Yuan ◽

Chaoyang Song ◽

...

Keyword(s):

External Disturbance ◽

Super Resolution ◽

Tactile Sensor ◽

Human Robot Interaction ◽

Tactile Sensors ◽

Dexterous Manipulation ◽

Robot Interaction ◽

Flexible Film ◽

Challenging Tasks ◽

External Forces

Human skin can sense subtle changes of both normal and shear forces (i.e., self-decoupled) and perceive stimuli with finer resolution than the average spacing between mechanoreceptors (i.e., super-resolved). By contrast, existing tactile sensors for robotic applications are inferior, lacking accurate force decoupling and proper spatial resolution at the same time. Here, we present a soft tactile sensor with self-decoupling and super-resolution abilities by designing a sinusoidally magnetized flexible film (with the thickness ~0.5 millimeters), whose deformation can be detected by a Hall sensor according to the change of magnetic flux densities under external forces. The sensor can accurately measure the normal force and the shear force (demonstrated in one dimension) with a single unit and achieve a 60-fold super-resolved accuracy enhanced by deep learning. By mounting our sensor at the fingertip of a robotic gripper, we show that robots can accomplish challenging tasks such as stably grasping fragile objects under external disturbance and threading a needle via teleoperation. This research provides new insight into tactile sensor design and could be beneficial to various applications in robotics field, such as adaptive grasping, dexterous manipulation, and human-robot interaction.

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The Energy-Efficient Processing of Fine Materials by the Micropyretic Synthesis Route

Journal of Nanomaterials ◽

10.1155/2012/727656 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

H. P. Li

Keyword(s):

Energy Efficient ◽

Processing Time ◽

Combustion Temperature ◽

Processing Parameters ◽

The Novel ◽

Diffusion Controlled ◽

Efficient Processing ◽

The One ◽

Processing Techniques ◽

Diffusion Controlled Reaction

Energy-efficient processing of TiB compound with nanowhiskers by micropyretic synthesis is investigated in this paper. Micropyretic synthesis not only offers shorter processing time but also excludes the requirement for high-temperature sintering and it is considered as the one of the novel energy-saving processing techniques. Experimental study and numerical simulation are both carried out to investigate the correlation of the processing parameters on the microstructures of the micropyretically synthesized products. The diffusion-controlled reaction mechanism is proposed in this study. It is noted that nanosize TiB whiskers only occurred when the combustion temperature is lower than the melting point of TiB but higher than the extinguished temperature. The results generated in the numerical calculation can be used as a helpful reference to select the proper route of processing nanosize materials. The Arrhenius-type plot of size and temperature is used to calculate the activation energy of TiB reaction. In addition to verifying the accuracy of the experimental measures, the reaction temperature for producing the micropyretically synthesized products with nanofeatures can be predicted.

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Camus's Absurd and the World of Melville's Confidence-Man

PMLA ◽

10.2307/461042 ◽

1967 ◽

Vol 82 (1) ◽

pp. 14-27

Author(s):

Leon F. Seltzer

Keyword(s):

Careful Analysis ◽

The Other ◽

The Novel ◽

The Past ◽

The World ◽

Critical Attention ◽

Confidence Man ◽

Ugly Duckling ◽

History Of ◽

The One

In recent years, The Confidence-Man: His Masquerade, a difficult work and for long an unjustly neglected one, has begun to command increasingly greater critical attention and esteem. As more than one contemporary writer has noted, the verdict of the late Richard Chase in 1949, that the novel represents Melville's “second best achievement,” has served to prompt many to undertake a second reading (or at least a first) of the book. Before this time, the novel had traditionally been the one Melville readers have shied away from—as overly discursive, too rambling altogether, on the one hand, or as an unfortunate outgrowth of the author's morbidity on the other. Elizabeth Foster, in the admirably comprehensive introduction to her valuable edition of The Confidence-Man (1954), systematically traces the history of the book's reputation and observes that even with the Melville renaissance of the twenties, the work stands as the last piece of the author's fiction to be redeemed. Only lately, she comments, has it ceased to be regarded as “the ugly duckling” of Melville's creations. But recognition does not imply agreement, and it should not be thought that in the past fifteen years critics have reached any sort of unanimity on the novel's content. Since Mr. Chase's study, which approached the puzzling work as a satire on the American spirit—or, more specifically, as an attack on the liberalism of the day—and which speculated upon the novel's controlling folk and mythic figures, other critics, by now ready to assume that the book repaid careful analysis, have read the work in a variety of ways. It has been treated, among other things, as a religious allegory, as a philosophic satire on optimism, and as a Shandian comedy. One critic has conveniently summarized the prevailing situation by remarking that “the literary, philosophical, and cultural materials in this book are fused in so enigmatic a fashion that its interpreters have differed as to what the book is really about.”

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STAND-UP MOTION SUPPORT BY A MOBILE MANIPULATOR SYSTEM WITH HIGH SPEED TACTILE SENSORS

International Journal of Information Acquisition ◽

10.1142/s0219878911002458 ◽

2011 ◽

Vol 08 (03) ◽

pp. 181-195

Author(s):

ZHAOXIAN XIE ◽

HISASHI YAMAGUCHI ◽

MASAHITO TSUKANO ◽

AIGUO MING ◽

MAKOTO SHIMOJO

Keyword(s):

Fuzzy Logic ◽

Feedback Control ◽

Experimental Verification ◽

High Speed ◽

Center Of Pressure ◽

Tactile Sensor ◽

Mobile Manipulator ◽

Tactile Sensing ◽

Robot Arm ◽

Tactile Sensors

As one of the home services by a mobile manipulator system, we are aiming at the realization of the stand-up motion support for elderly people. This work is charaterized by the use of real-time feedback control based on the information from high speed tactile sensors for detecting the contact force as well as its center of pressure between the assisted human and the robot arm. First, this paper introduces the design of the tactile sensor as well as initial experimental results to show the feasibility of the proposed system. Moreover, several fundamental tactile sensing-based motion controllers necessary for the stand-up motion support and their experimental verification are presented. Finally, an assist trajectory generation method for the stand-up motion support by integrating fuzzy logic with tactile sensing is proposed and demonstrated experimentally.

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