Relationship between the output of CMC tactile sensor and the shear force of its sensor element during tactile sensation

SUMMARYThe tactile sensor is constructed as a part of the finger of a parallel jaw hand; it is of the size of a finger and allows for a large displacement of the sensor element in response to force. The structure of the tactile sensor incorporates 20 successively and closely aligned elements, which allow for a 2.5 mm maximum displacement for each element. In the described experiments we present the capabilities of the tactile sensor. The tactile sensor has the functions of: 1) discriminating the shape of the partial surface of an object; and 2) tracing by finger on the surface along the profile of an object.

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A Microfluidic-Based Tactile Sensor for 3-DOF Force/Torque Detection

Volume 3: Advanced Fabrication and Manufacturing; Emerging Technology Frontiers; Energy, Health and Water- Applications of Nano-, Micro- and Mini-Scale Devices; MEMS and NEMS; Technology Update Talks; Thermal Management Using Micro Channels, Jets, Sprays ◽

10.1115/ipack2015-48133 ◽

2015 ◽

Author(s):

Yichao Yang ◽

Zhili Hao

Keyword(s):

Soft Lithography ◽

Shear Force ◽

Normal Force ◽

Three Dimensional ◽

Tactile Sensor ◽

Degree Of Freedom ◽

Experimental Results ◽

Torque Sensor ◽

Resistance Increase ◽

3D Microstructure

This paper reports on a microfluidic-based tactile sensor capable of detecting forces along two directions and torque about one direction. The 3-Degree-Of-Freedom (3-DOF) force/torque sensor encompasses a symmetric three-dimensional (3D) microstructure embedded with two sets of electrolyte-enabled distributed resistive transducers underneath. The 3D microstructure is built into a rectangular block with a loading-bump on its top and two microchannels at its bottom. Together with electrode pairs distributed along the microchannel length, electrolyte in each microchannel functions as a set of three resistive transducers. While a normal force results in a resistance increase in the two sets of transducers, a shear force causes opposite resistance changes in the two sets of transducers. Conversely, a torque leads to the opposite resistance changes in the two side transducers in each set. Soft lithography and CNC molding are combined to fabricate a prototype tactile sensor. The experimental results validate the feasibility of using this microfluidic-based tactile sensor for 3-DOF force/torque detection.

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Force Characteristics for Fine Deformation of CMC Touch Sensor and Estimation of Force Variance Using Hybrid Tactile Sensor System

Journal of Robotics and Mechatronics ◽

10.20965/jrm.2012.p0423 ◽

2012 ◽

Vol 24 (3) ◽

pp. 423-429

Author(s):

Takuya Kawamura ◽

◽

Ko Nejigane ◽

Kazuo Tani ◽

Hironao Yamada

Keyword(s):

Tactile Sensor ◽

Force Sensor ◽

Sensor System ◽

Compression Force ◽

Sensor Element ◽

Silicon Rubber ◽

Touch Sensor ◽

Slight Movement ◽

Force Characteristics

Having previously proposed a hybrid tactile sensor system consisting of a Carbon Micro-Coil (CMC) touch sensor and a force sensor, the authors have been developing a method of measuring deformation of micrometer order, force variance of 10 gram order, and compression force when an object touches a sensor element and moves slightly. In this paper, to measure the force variance for deformation of several micrometers using the CMC touch sensor, the force characteristics of the CMC touch sensor are investigated. The CMC sensor element is made of silicon rubber containing CMCs several micrometers in diameter. It is considered that the sensor element constitutes an LCR circuit, and the CMC touch sensor, deformed mechanically, produces signals due to the modification of the circuit. In the experiment detailed in this paper, to clarify the characteristics of the CMC sensor with respect to the parameters of force and deformation, the outputs of the CMC sensor and the force sensor for deformation in the range of 1 to 9 µm are sampled. As a result, it is found that the force characteristics of the CMC touch sensor are almost linear in terms of force variance within the range of 0 to 1 N, regardless of a compression force of less than 3 N. Finally, to evaluate the performance of the sensor system, force variance for a slight movement of an object touching the sensor element is estimated in an experiment.

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Relationship between output of CMC tactile sensor and mechanical characteristics of its sensor element during compressive deformation

The Proceedings of Conference of Tokai Branch ◽

10.1299/jsmetokai.2017.66.318 ◽

2017 ◽

Vol 2017.66 (0) ◽

pp. 318

Author(s):

Takahito IMAI ◽

Kigen TOTANI ◽

Takuya KAWAMURA ◽

Katutoshi OTSUBO ◽

Hironao YAMADA

Keyword(s):

Mechanical Characteristics ◽

Tactile Sensor ◽

Compressive Deformation ◽

Sensor Element

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Flexible Tactile Sensor Skin Using Wireless Sensor Elements Coupled with 2D Microwaves

Journal of Robotics and Mechatronics ◽

10.20965/jrm.2010.p0784 ◽

2010 ◽

Vol 22 (6) ◽

pp. 784-789 ◽

Cited By ~ 7

Author(s):

Hiroyuki Shinoda ◽

◽

Hiromasa Chigusa ◽

Yasutoshi Makino ◽

◽

...

Keyword(s):

Signal Transmission ◽

Tactile Sensor ◽

Electrical Contacts ◽

Experimental Results ◽

Wireless Sensor ◽

Two Dimensional ◽

Conductive Layer ◽

Arc Length ◽

Sensor Element ◽

Rfid Tag

The stretchable sensor skin we propose uses microwaves propagating in a two-Dimensional Signal Transmission (2DST) sheet. A small tactile sensor chip with a pair of Resonant Proximity Connectors (RPCs) couples with 2D microwaves carrying signals. Chip operating power is also supplied by 2D microwaves. The RPC is a spiral electrode whose arc length is a quarter of the electromagnetic wavelength. Chip operating power is supplied by 2D microwaves. Sensor chips are connected to the 2DST sheet by RPCs without electrical contacts anywhere on the sheet. Resonance induced at the electrode reduces impedance between the connector and the conductive layer of the 2DST sheet, enabling sensor chips to be connected stably to the sheet. Experimental results on the RPC show the concept to be effective. We fabricated a 1-bit (touch detection) tactile sensor element consisting of a RFID-tag and RPCs, and confirmed in experiments that the sensor element operates in a stretchable 2DST sheet.

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A Model for Estimating Tactile Sensation by Machine Learning Based on Vibration Information Obtained while Touching an Object

Sensors ◽

10.3390/s21237772 ◽

2021 ◽

Vol 21 (23) ◽

pp. 7772

Author(s):

Fumiya Ito ◽

Kenjiro Takemura

Keyword(s):

Sensory Evaluation ◽

Statistical Evaluation ◽

Tactile Sensor ◽

Added Value ◽

Tactile Sensation ◽

Tactile Sensing ◽

Neural Firing ◽

Estimation Model ◽

Important Indicator ◽

Sensing Technology

The tactile sensation is an important indicator of the added value of a product, and it is thus important to be able to evaluate this sensation quantitatively. Sensory evaluation is generally used to quantitatively evaluate the tactile sensation of an object. However, statistical evaluation of the tactile sensation requires many participants and is, thus, time-consuming and costly. Therefore, tactile sensing technology, as opposed to sensory evaluation, is attracting attention. In establishing tactile sensing technology, it is necessary to estimate the tactile sensation of an object from information obtained by a tactile sensor. In this research, we developed a tactile sensor made of two-layer silicone rubber with two strain gauges in each layer and obtained vibration information as the sensor traced an object. We then extracted features from the vibration information using deep autoencoders, following the nature of feature extraction by neural firing due to vibrations perceived within human fingers. We also conducted sensory evaluation to obtain tactile scores for different words from participants. We finally developed a tactile sensation estimation model for each of the seven samples and evaluated the accuracy of estimating the tactile sensation of unknown samples. We demonstrated that the developed model can properly estimate the tactile sensation for at least four of the seven samples.

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