Inertial motion capture has garnered considerable attention within the manufacturing industry for ergonomic assessments due to high reliability and fewer constraints compared to alternative posture tracking direct measurement tools. However, these wearable systems, while ensuring reliability and precision in the results, also introduce a degree of invasiveness. Hence, user experience becomes an important aspect for design and development of such systems. This paper reveals major user experience issues resulting from an experimental study for promoting user-centred design of wearable systems.

The design and characterization of a new broadband small patch antenna, based on an innovative magneto-dielectric material and suitable for wearable applications at 868 MHz, is presented. To reduce antenna dimensions, while preserving its radiation and matching performance, a barium-strontium hexaferrite Ba0.75Sr0.25Fe12O19 has been synthesized as the antenna substrate to achieve magnetic permeability double than vacuum in the band of interest. First material realization is characterized and dispersive permittivity and permeability behaviors are included in the design of a small patch antenna with a shorting-plate. A button-size realization is obtained and its suitability for wearable applications is numerically and experimentally demonstrated on body with and without the presence of conductive shielding. Very good agreement with measurements is demonstrated for both matching and radiation performance of the antenna.