In this paper a stain sensor to measure large strain (80%) in textiles is presented. It consists of a mixture of 50wt-% thermoplastic elastomer (TPE) and 50wt-% carbon black particles and is fiber-shaped with a diameter of 0.315mm. The attachment of the sensor to the textile is realized using a silicone film. This sensor configuration was characterized using a strain tester and measuring the resistance (extension-retraction cycles): It showed a linear resistance response to strain, a small hysteresis, no ageing effects and a small dependance on the strain velocity. The total mean error caused by all these effects was ±5.5% in strain. Washing several times in a conventional washing machine did not influence the sensor properties. The paper finishes by showing an example application where 21 strain sensors were integrated into a catsuit. With this garment, 27 upper body postures could be recognized with an accuracy of 97%.

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In this paper we report the successful development of pressure sensitive textile prototypes based on flexible optical fibers technology. Our approach is based on thermoplastic silicone fibers, which can be integrated into woven textiles. As soon as pressure at a certain area of the textile is applied to these fibers they change their cross section reversibly, due to their elastomeric character, and a simultaneous change in transmitted light intensity can be detected. We have successfully manufactured two different woven samples with fibers of 0.51 and 0.98 mm diameter in warp and weft direction, forming a pressure sensitive matrix. Determining their physical behavior when a force is applied shows that pressure measurements are feasible. Their usable working range is between 0 and 30 N. Small drifts in the range of 0.2 to 4.6%, over 25 load cycles, could be measured. Finally, a sensor array of 2 × 2 optical fibers was tested for sensitivity, spatial resolution and light coupling between fibers at intersections.

Soft robots are, due to their softness, inherently safe and adapt well to unstructured environments. However, they are prone to various damage types. Self‐healing polymers address this vulnerability. Self‐healing soft robots can recover completely from macroscopic damage, extending their lifetime. For developing healable soft robots, various formative and additive manufacturing methods have been exploited to shape self‐healing polymers into complex structures. Additionally, several novel manufacturing techniques, noted as (re)assembly binding techniques that are specific to self‐healing polymers, have been created. Herein, the wide variety of processing techniques of self‐healing polymers for robotics available in the literature is reviewed, and limitations and opportunities discussed thoroughly. Based on defined requirements for soft robots, these techniques are critically compared and validated. A strong focus is drawn to the reversible covalent and (physico)chemical cross‐links present in the self‐healing polymers that do not only endow healability to the resulting soft robotic components, but are also beneficial in many manufacturing techniques. They solve current obstacles in soft robots, including the formation of robust multi‐material parts, recyclability, and stress relaxation. This review bridges two promising research fields, and guides the reader toward selecting a suitable processing method based on a self‐healing polymer and the intended soft robotics application.

Until now, lead zirconate titanate (PZT)-based ceramics are the most widely used in piezoelectric devices. However, the use of lead is being avoided due to its toxicity and environmental risks. Indeed, the attention has been moved to lead-free ceramics, especially on potassium sodium niobate (KNN)-based materials, due to growing environmental concerns. These materials are technologically interesting. For applications such as actuators, an electromechanical coupling providing high strain with high force, e.g, fuel injection, ultrasonic motor, etc., is required, Moreover, in the current context, the new technologies evolve toward the miniaturization of the conventional electronic devices. Herein, we have developed microfiber ceramics of KNN-based composition, which yield a high strain value with S max as high as 0.17% at 3 kV mm −1 . According to our results, this phenomenon can be explained by an extrinsic effect that favors the internal relaxation of the system. To reach this breakthrough, a sintering mechanism has been established, which allows for correlating the extrinsic factors of the system with electromechanical properties of the ceramic fibers. We believe that the general strategy and design principles described in this study will open new avenues in developing of (K,Na)NbO 3 -based lead-free piezoelectric fibers with enhanced properties for high-precision sensor and actuator applications.