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The purpose of this paper is to analyse the possibilities of mechanical switch replacement by capacitive film touch sensor in applications requiring high reliability and short response time. Advantage of replacing mechanical switch by capacitive touch sensor is no mechanical wear and possible implementation of sensor in application where the switch could not be used or where the flexibility of the sensor substrate is required. The aim of this work is to develop a capacitive touch sensor with the advantage of maximum mechanical resistance, short response time and high sensitivity.

Based on various possible sensors layouts, the authors realized 18 different (14 self-capacitance and four mutual capacitance) topologies of capacitive sensor for touch applications. Three different technologies – PCB, LTCC and polymer technology – were used to characterize sensor’s behaviour. For precise characterization of different layouts realized on various substrates, the authors used integrated circuit FDC2214 capacitance-to-digital converter.

Sensing range of the capacitive touch (proximity) sensor is affected by the per cent of area covered by the sensor, and it does not depend on topology of sensor. The highest sensing range offers PCB technology. Flexible substrates can be used as proper substituent to rigid PCB.

The novelty of this work lies in finding the touch capacitive sensors that allow shorter switching times compared to standard mechanical switches.

The purpose of this study is to demonstrate the usage of three-dimensionally (3D) printed polylactic acid (PLA)-carbon black (CB) conductive polymer composite in the measurement of the void fraction and liquid level.

PLA-CB conductive polymer composite is 3D printed through fused deposition modelling (FDM) technique and used as a capacitive sensor for void fraction measurement and liquid level sensing. The sensitivity of 3D printed ring and concave type capacitive sensors are compared for void fraction measurement. The effect of electrode length, thickness and pipe dimension on the capacitance achievable for the particular void fraction is studied. Concept of fringing capacitance is used for the sensing of liquid level.

Compared to the concave design comprising four electrodes, the ring-type capacitive sensor produced better results in void fraction measurement. Increase in pipe diameter and electrode length results in the enhancement of capacitance arising from specific void fraction. For a 100 mm diameter pipe, the capacitance of the 150 mm-long concave electrode (0.4 mm thick) increased from 9.98 to 67.77 pF as the void fraction decreased from 100% to 0%. Development of the fringing capacitance in 3D printed PLA-CB composite helps in the measurement of liquid level. Both parallel finger topology and interdigital electrode configuration are able to sense the liquid level.

Ability of the 3D printed conductive PLA-CB composite to act as a capacitive sensor is experimentally analysed. Performance of different electrode configuration is tested for both void fraction measurement and liquid level sensing. Results of experimentation prove that FDM printed PLA-CB composite is suitable for the void fraction and liquid level measurement.

This paper presents a novel interface system to aid people with visual impairment to become proficient with operating unfamiliar devices. The system works by adding touch sensors that trigger audio tags to tactile controls. The touch sensors trigger the audio tags before the control is activated.

The paper describes how several devices were enhanced with the new technology, tested and evaluated. Initial informational interviewing with visually impaired people was followed by user studies with blindfolded but visually able people. A final evaluation of the system was conducted by a visually impaired group.

This paper shows that the technology is of benefit to a visually impaired user when using a complex unfamiliar device.

This novel application of touch sensors coupled with audio tags has the potential to benefit visually impaired people. This technology can easily be incorporated into commercial devices. The idea can also be implemented using off the shelf development boards coupled with smart phones.

The purpose of this paper is to present TalkBox, an affordable and open-source communication board for users with communication or speech disorders. Making and tinkering methods are combined with community engagement and participatory design to create a democratic and accessible approach to assistive technology design.

The authors employed a community-engaged participatory design methodology where we incorporated input from stakeholders into the design of the interface. Close collaboration with our community partner allowed us to make informed decisions on different aspects of the design from sourcing of the material to testing the prototype.

Through describing TalkBox, the paper presents a concrete example of how assistive technology can be designed and deployed more democratically, how collaborations between academia and community partners can be established, and how the design reflects different aspects of the methodology used.

This paper explores the question of how can open-source technology and making methods contribute to the development of more affordable and inclusive designs through a concrete example.

The purpose of this paper is to describe the reviews of past research work on various in-pipe robotic systems and their operations. This investigation has been focussed on the implemented methodologies for performing in-pipe cleaning and inspection tasks.

This work has been concentrated on review of various sensors used in robots to perform in-pipes inspection operation for determining flaws/cracks, corrosion-affected areas, blocks and coated paint thickness. Various actuators like DC motors, servo motors, pneumatic operated and hydraulic operated are discussed in this review analysis to control the motion of various mechanical components of the robot.

In the current analysis, categorisation of various pipe cleaning robots according to their mechanical structure has been addressed. A lot of information has been gathered regarding the control of in-pipe robots for performing inspection and cleaning tasks.

In this paper, various in-pipe cleaning and inspection techniques have been studied. Necessary information provided regarding different types of in-pipe robots like PIG, wall-pressed, walking, wheel and inchworm. This investigation provides a through literature on various types of sensors like ultrasonic, magnetic, touch, light amplification by stimulated emission of radiation, X-ray, etc., that have been used for inspection and detection of flaws in the pipe.

The purpose of this study is to develop an output model to extract surface microstructure characteristics of different objects, so as to predict the response of the output voltage obtained from tactile texture sensor.

The model is based on the consideration of the inverse-magnetostrictive effect, the flexure mode, the linear constitutive equations and the strain principle.

This research predicts and investigates the effect of the texture properties on the tactile texture sensor output characteristics.

The surface texture characteristic is regarded to be important information to evaluate and recognize the object.

User authentication is generally used to protect personal information such as phone numbers, photos and account information stored in a mobile device by limiting the user to a specific person, e.g. the owner of the device. Authentication methods with password, PIN, face recognition and fingerprint identification have been widely used; however, these methods have problems of difficulty in one-handed operation, vulnerability to shoulder hacking and illegal access using fingerprint with either super glue or facial portrait. From viewpoints of usability and safety, strong and uncomplicated method is required.

In this paper, a user authentication method is proposed based on grip gestures using pressure sensors mounted on the lateral and back sides of a mobile phone. Grip gesture is an operation of grasping a mobile phone, which is assumed to be done instead of conventional unlock procedure. Grip gesture can be performed with one hand. Moreover, it is hard to imitate grip gestures, as finger movements and grip force during a grip gesture are hardly seen by the others.

The feature values of grip force are experimentally investigated and the proposed method from viewpoint of error rate is evaluated. From the result, this method achieved 0.02 of equal error rate, which is equivalent to face recognition.

Many researches using pressure sensors to recognize grip pattern have been proposed thus far; however, the conventional works just recognize grip patterns and do not identify users, or need long pressure data to finish confident authentication. This proposed method authenticates users with a short grip gesture.

In light of growing interest in the maker movement and electronic textiles (e-textiles) as an educational technology, the purpose of this paper is to characterize competence change in undergraduate students who participated in a semester-length course that used e-textiles.

This qualitative and exploratory research study used semi-structured pre- and post-interviews with undergraduate students (N=7) thinking aloud through novel tasks in order to understand their learning from a semester-long course involving e-textiles. This design was intended to elicit student thinking with commercial toys that differed from the types of projects they had completed in their course. A coding scheme was developed and organized into an analytical rubric to map depth of understanding in the three spheres of circuitry, computation, and crafting. Select cases of pre-post change were identified to illustrate growth in specific content spheres.

Students’ ability to reason through novel tasks showed growth in each sphere, provided that the student did not begin with a full level of sophistication in a particular area during the pre-interview. Although students may not reach normative or expert-like competence, there are demonstrable indications of growth for each of the dimensions.

As e-textiles are increasingly turned to educationally, the creation and presentation of a rubric for describing competence in three spheres, especially the previously understudied area of crafting knowledge in e-textiles, is itself a useful contribution to the field. This is also an extension of e-textiles learning research into undergraduate instruction, an as-yet understudied setting for maker education.