Recent advances in virtual reality and robotic technologies have allowed researchers to explore the mechanisms underlying bodily aspects of self-consciousness which are largely attributed to the multisensory and sensorimotor processing of bodily signals (bodily self-consciousness, BSC). One key contribution to BSC, that is currently poorly addressed due to the lack of a wearable solution, concerns realistic collision sensations on the torso. Here, we introduce and validate a novel torso-worn force display, the Cogno-vest, to provide mechanical touch on the user's back in a sensorimotor perception experiment. In a first empirical study, we characterized human finger poking (N=28). In order to match these poking characteristics and meet the wearability criteria, we used bi-directional, push-pull solenoids as a force actuator in the Cogno-vest. Subsequently, and based on an iterative, multidisciplinary design procedure, a bodyconforming, unisex, torso-worn force display was prototyped. Finally, we conducted a behavioral study that investigated BSC in 25 healthy participants by introducing conflicting sensorimotor signals between their hand and torso (back). Using the final reiteration of the Cogno-vest we successfully replicated previous findings on illusory states of BSC, characterized by presence hallucinations (PH) and passivity symptoms, and achieved higher illusion ratings compared to static conditions used in prior studies.

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Fluidic systems enable actuation in various applications, such as automotive, medical, and industrial robotics. Miniaturized valves constitute a fundamental controlling element of modern fluidic systems, intriguing the interest of many researchers. This letter presents the design, implementation, and experimental validation of a miniaturized magnetorheological valve. The valve is highly efficient due to its capability of sustaining high loads with low energy consumption. This work includes the estimation strategy for the sustained load. Magnetorheological fluid is used both as an actuation fluid and as control medium. The inner iron core of the traditional magnetorheological valve is replaced with an AlNiCo-5 rod. The latter provides the possibility of magnetic energy storage, without continuous power supply. This changes the actuation mechanism from an electromagnet to an electropermanent magnet. The valve's capability to sustain pressure up to 1010 kPa, for a volume of 353 mm 3 , is demonstrated experimentally. The fluid flow rate when the valve is open is 459 mm 3 /s for a pressure difference of 993 kPa. The corresponding power consumption is negligible in steady-state condition, while consuming 15.3 mJ when activated and 6 mJ when deactivated. The experimental results also validate the possible tunability of the pressure sustaining capability of the valve.

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Magnetorheological (MR) valves have been included in many innovative engineering systems, such as dampers, clutches, or brakes, with different fields of application. Their role serves actuation purposes, while integrated displacement and velocity sensing in the actuators has been studied, as well.In this paper, we present the working principle, design, and preliminary results of a miniature MR valve with pressure selfsensing capabilities that exploits the electromagnetic induction phenomenon. The valve can work in a pressure range from 200 kP a to 700 kP a, supplied by a current of a maximum 0.3 A. The suggested valve design is realized with two coils, one for the current application and the magnetic field creation and one for the sensing of the electromagnetic induction. A specially designed test-bench, that facilitates MR fluid flow and pressure regulation, was used for the experimental procedures.