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Purpose – The purpose is to expand multimodal composition frameworks and practices to include tactile design and use of maker technologies, situated in a larger context of designing for equity and increasing access to picture books for children with visual impairments.

Design – As part of the Build a Better Book project, we designed workshops to engage students in composing tactile books enhanced with sound and Braille for young children with visual impairments. Education undergraduates in a children’s literature class crafted tactile retellings over a 2-session workshop, and high school students in an ELA class designed and fabricated 3D printed tactile books over several weeks.

Findings – Both pre-service candidates and high school students developed awareness of the importance of inclusive, equity-oriented design of picture books, and especially for children with visual impairments. They collaborated in teams, developing design skills manipulating texture, shape, size and spatial arrangement to express their tactile retellings and enhanced meaning with sound. The high school students had more opportunity to build technical and computational thinking through their use of Makey Makey, Scratch, and TinkerCad.

Practical Implications – Multimodal composition and making can be effectively integrated into pre-service candidates’ literacy education, as well as high school English Language Arts, to develop multimodal communication and inclusive design skills and values. Success depends on interdisciplinary expertise (e.g., children’s books, tactile design, making technologies, etc.), and sufficient access to physical and digital materials and tools.

Reviews the benefits and potential application of tactile sensors for use with robots.

Includes the most recent advances in both the design/manufacturing of various tactile sensors and their applications in different industries. Although these types of sensors have been adopted in a considerable number of areas, the applications such as, medical, agricultural/livestock and food, grippers/manipulators design, prosthetic, and environmental studies have gained more popularity and are presented in this paper.

Robots can perform very useful and repetitive tasks in controlled environments. However, when the robots are required to handle the unstructured and changing environments, there is a need for more elaborate means to improve their performance. In this scenario, tactile sensors can play a major role. In the unstructured environments, the robots must be able to grasp objects (or tissues, in the case of medical robots) and move objects from one location to another.

In this work, the emphasis was on the most interesting and fast developing areas of the tactile sensors applications, including, medical, agriculture and food, grippers and manipulators design, prosthetic, and environmental studies.

The paper aims to discuss the design, fabrication, communication, testing, and simulation of a new tactile probe called Elastirob used to measure the modulus of elasticity of biological soft tissues and soft materials.

Both finite element modeling and experimental approaches were used in this analysis. Elastirob, with the ability to apply different rates of strain on testing specimens, is accompanied by a tactile display called TacPlay. This display is a custom‐designed user‐friendly interface and is able to evaluate the elasticity in each part of the stress‐strain curve.

A new device is being constructed that can measure the modulus of elasticity of a sensed object. The results of Elastirob applied on two specimens are reported and compared by the results of experiments obtained by an industrial testing machine. Acceptable validations of Elastirob were achieved from the comparisons.

The designed system can be miniaturized to be used in minimally invasive surgeries in the future.

Elastirob determines the elasticity by drawing the stress‐strain curve and then calculating its slope. The combination of the force sensing resistor, microcontroller and stepper motor provides Elastirob with the ability to apply different rates of strain on testing specimens.

It can be employed in both in vivo and in vitro tests for measuring stiffness of touch objects. For the first time, a device has been designed and tested which is a few orders of magnitude smaller than its industrial counterparts and has considerably lower weight.

Tactile sensation is an important sensory function for robots in contact with the external environment. To better acquire tactile information about objects, this paper aims to propose a three-layer structure of the interdigital flexible tactile sensor.

The sensor consists of a bottom electrode layer, a middle pressure-sensitive layer and a top indenter layer. First, the pressure sensitive material, structure design, fabrication process and circuit design of the sensor are introduced. Then, the calibration and performance test of the designed sensor is carried out. Four functions are used to fit and calibrate the relationship between the output voltage of the sensor and the contact force. Finally, the contact force sensing test of different weight objects and the flexible test of the sensor are carried out.

The performance test results show that the sensitivity of the sensor is 0.93 V/N when it is loaded with 0–3 N and 0.23 V/N when it is loaded with 3–5 N. It shows good repeatability, and the cross-interference between the sensing units is generally low. The contact force sensing test results of different weight objects show that the proposed sensor performs well in contact force. Each part of the sensor is a flexible material, allowing the sensor to achieve bending deformation, so that the sensor can better perceive the contact signs of the grasped object.

The sensor can paste the surface of the paper robot’s gripper to measure the contact force of the grasping object and estimate the contour of the object.

In this paper, a three-layer interdigital flexible tactile sensor is proposed, and the structural parameters of the interdigital electrode are designed to improve the sensitivity and response speed of the sensor. The indenter with three shapes of the prism, square cylinder and hemisphere is preliminarily designed and the prism indenter with better conduction force is selected through finite element analysis, which can concentrate the external force in the sensing area to improve the sensitivity. The sensor designed in this paper can realize the measurement of contact force, which provides a certain reference for the field of robot tactile.

The hands of intelligent robots perceive external stimuli and respond effectively according to tactile or pressure sensors. However, the traditional tactile and pressure sensors cannot perform human-skin-like intelligent properties of high sensitivity, large measurement range, multi-function and flexibility simultaneously. The purpose of this paper is to present a flexible tactile-pressure sensor based on hyper-elastics polydimethylsiloxane and plate capacitance.

With regard to this problem, this paper presents a flexible tactile-pressure sensor based on hyper-elastics PDMS and plate capacitance. The sensor has a size of 10 mm × 10 mm × 1.3 mm and is composed of four upper electrodes, one middle driving electrode and one lower electrode. The authors first analyzed the structure and the tactile-pressure sensing principle of human skin to obtain the design parameters of the sensor. Then they presented the working principle, material selection and mechanical structure design and fabrication process of the sensor. The authors also fabricated several sample devices of the sensor and carried out experiments to establish the relationship between the sensor output and the pressure.

The results show that the tactile part of the sensor can measure a range of 0.05-1N/mm² micro pressure with a sensitivity of 2.93 per cent/N and a linearity of 0.03 per cent. The pressure part of the sensor can measure a range of 1-30N/mm² pressure with a sensitivity of 0.08 per cent/N and a linearity of 0.07 per cent.

This paper analyzes the tactile and pressure sensing principles of human skin and develop an intelligent sensitive human-skin-like tactile-pressure sensor for intelligent robot perception systems. The sensor can achieve to imitate the tactile and pressure function simultaneously with a measurement resolution of 0.01 N and a spatial resolution of 2 mm.

This paper aims to design a new full‐body tactile sensor which is essential for the application of personal service robot similar to human skin.

The largest difficulty for designing a full‐body tactile sensor is the huge number of output connections. The sensor introduced in this paper is a special multi‐layer structure, which could minimize the output connections while sensing both the position and force information. Since it is made of conductive and non‐conductive textiles, the sensor could be used to cover the curved surface of robot body.

With better structure design, output connectors and signal measurement times could be dramatically reduced.

Sensor area and performance are limited by the sensitivity of the measurement circuits.

Introduces an innovate design of full‐body tactile sensor.

Robotic surgery is limited by the lack of haptic feedback to the surgeon. The addition of tactile information may enable surgeons to feel tissue characteristics, appropriately tension sutures, and identify pathologic conditions. Tactile feedback may also enable expansion of minimally invasive surgery to other surgical procedures and decrease the learning curve associated with robotic surgery. This paper aims to explore a system to provide tactile feedback.

A pneumatic balloon‐based system has been developed to provide tactile feedback to the fingers of the surgeon during robotic surgery. The system features a polydimethyl siloxane actuator with a thin‐film silicone balloon membrane and a compact pneumatic control system. The 1.0 × 1.8 × 0.4 cm actuators designed for the da Vinci system feature a 3 × 2 array of 3 mm inflatable balloons.

The low‐profile pneumatic system and actuator have been mounted directly onto the da Vinci surgical system. Human perceptual tests have indicated that pneumatic balloon‐based tactile input is an effective means to provide tactile information to the fingers of the surgeon.

Application of a complete tactile feedback system is limited by current force sensing technologies.

The actuators have been designed such that they can be mounted directly onto the hand controls of the da Vinci robotic system, and are scalable such that they can be applied to various robotic applications.

The tactile sensor with array structure normally has the defects of existing nondetection zone, complex and nonstretchable structure. It is difficult to seamlessly attach to the surface of the robot. For this reason, this paper proposes a method to prepare nonarray structure tactile sensor directly on the surface of the robot by spraying process.

Based on the principle of gradient potential distribution, the potential fields are constructed in two different directions over the conductive film in time-sharing. The potentials at touching position in the two directions are detected to determine the coordinate of the touching point. The designed tactile sensor based on this principle consists of only three layers. Its bottom layer is designed as a weak conductive film made of graphite coating and used to construct the potential field. It can be sprayed either on PET substrate or directly on robot surface.

The radial basis function neural network is used for remodeling the potential distribution, which can effectively solve the problem of nonlinear potential distribution caused by irregular sensor shape, and uneven conductivity at different points of the spraying coating. The simulation and experimental results show that the principle of the proposed tactile sensor used for touching position detection is feasible to be applied to complex surfaces of the robot.

This paper proposed a nonarray customizable tactile sensor based on the spraying process. The sensor has a simple structure, and only five lead wires are needed to realize the coordinate detection of the touch position.

The mainstream of current research work in array tactile sensors concentrates on using a soft compliant membrane as a means of transmitting the effect of variable external stimuli to the discrete sensing elements. The soft compliant devices are usually made of a thin flexible substrate such as pressure sensitive pads, conductive materials, conductive coatings, piezoelectric polymers or elastomers. A large number of tactile sensor designs using these types of materials have been investigated by researchers. These include the use of anisotropically conductive silicone rubber (ACS), sponges containing carbon particles or felted carbon fibres, piezoelectric polymers such as polyvinylidene fluoride (PVF2) and conductive elastomers such as Dynacom materials consisting of silicone rubber mixed with metallic compounds.

This paper describes the design, fabrication, testing, and mathematical modeling of a supported membrane type polyvinylidene fluoride (PVDF) tactile sensor. Using the designed membrane type sensor (MTS), it is shown that the entire surface of the PVDF film can be employed as a means of detecting the force magnitude and its application point. This is accomplished by utilizing only three sensing elements. Unlike the array type tactile sensors, in which the regions between the neighboring sensing elements are not active, all the surface points of the sensor are practically active in this MTS. A geometric mapping process is introduced, thereby, the loci of the isocharge contours for the three sensing elements are determined by applying force on various points of the sensor surface. In order to form a criterion for the comparison between the experimental findings and the theoretical analysis data, and also to determine the magnitude of the stresses generated in the membrane, finite element modeling is used. The correlation between the theoretical predictions and experimental findings is proven to be reasonable. Potentially, the designed MTS can be incorporated into various medical probes for tactile imaging.