Tactile information is usually important for object manipulation and grasping. Typically, soft hands and tactile sensors can deform passively and contribute to stable grasping. In particular, soft tactile sensors that use conductive materials as sensor elements can acquire contact information, including the contact position and pressure; however, this tactile information cannot be classified. This study attempts to classify tactile information based on conductive material arrangements. To this end, we develop a soft tactile sensor composed of a silicone rubber body with two channels filled with a conductive material. The two channels are arranged so that they are parallel from the top view and angled with different slopes from the side view. Our experimental data reveal that the contact position parallel to the channels can be determined based on the resistance changes in the two channels, whereas the pressure can be obtained through a model based on the estimated value of the contact position.
In this letter, we present a smart glove for Tactile Internet applications. The individual finger motions are measured via resistive strain sensors. The strain sensors are directly integrated with the textile glove and are produced in an automated process. The sensor glove is integrated with sensor conditioning, controller, wireless frontend, and battery. We investigate the measured sensor data for a variety of gestures, demonstrating the good quality of the data allowing for easy and low-energy gesture recognition.
Humidity is one of the most relevant physical parameters to sense and control for a wide range of commercial and industrial applications. Consequently, there is continuing demand for the development of innovative and sustainable humidity sensor solutions. Here, the development and characterization of fully additively manufactured, highly sensitive, resistive Chitosan-based humidity sensors on flexible thermoplastic polyurethane (TPU) foil, as well as on a glass carrier substrate are presented. The sensors unite aspects of sustainability and high performance in a broad humidity range (20–90%rH). The humidity response follows an exponential curve progression with relative changes in the resistance per %rH of 6.9% and 5.7% for the glass carrier sensor and the TPU sensor, respectively. In absolute values, this means that the Chitosan-based sensors are particularly sensitive in the low humidity range with a vast dynamic range (ten times larger compared to commonly used capacitive humidity sensors). The flexible sensor on the TPU substrate shows great stability even after repeated bending. In addition, the combination of flexible and biocompatible materials (TPU and Chitosan) with additive manufacturing technologies makes the sensor particularly sustainable while having great potential for a plethora of biomedical applications.