Abstract: The invention provides circuits, systems and methods for dielectric elastomer device (DED) self-sensing. The circuit comprises a first DED coupled or adapted for coupling to a first voltage source (for providing an actuating or priming signal, for example); a current sensor provided in series with the first DED; and an oscillating signal source coupled to the first DED and adapted to cause an oscillation in a voltage across the DED, wherein the oscillating signal source is decoupled from the first voltage source.

Abstract: A self-powered converter and more particularly, though not exclusively, a step-down voltage converter requiring no external power supply, which is particularly suited to converting a high-voltage, low energy input from an intermittent DC power source to a low voltage DC output. There is provided an electrical converter for converting input power from an intermittent power source to a different voltage for a load, the converter comprising: a switched converter circuit coupled to an input for coupling to the power source and to an output for coupling to the load, the switched converter circuit arranged to convert power from the input to a different voltage and supply this to the output; a controller for controlling the switched converter circuit dependent on an input voltage at the input.

Abstract: The present invention relates to pliable capacitive structures such as dielectric elastomers and similar smart materials which can be used for sensing externally applied strains which can be inferred by the determining the capacitance of the structure/material. There is provided an apparatus comprising a pliable capacitive structure for use in detecting shape or strain changes, the pliable capacitive structure having a dielectric material positioned between two electrodes; means for applying a steady-state voltage across the two electrodes; and means for determining changes in capacitance of the pliable capacitive structure using said steady state voltage.

Abstract: The invention provides circuits, systems and methods for dielectric elastomer device (DED) self-sensing. The circuit comprises a first DED coupled or adapted for coupling to a first voltage source (for providing an actuating or priming signal, for example); a current sensor provided in series with the first DED; and an oscillating signal source coupled to the first DED and adapted to cause an oscillation in a voltage across the DED, wherein the oscillating signal source is decoupled from the first voltage source.

Abstract: The invention provides a passive converter comprising an input for electrical coupling to an intermittent or variable power source, an output for electrical coupling to load, and a conversion circuit for converting from a first voltage level of the input to a second voltage level suitable for the output, wherein the conversion circuit includes a passive switching circuit adapted to passively couple the input to the output when the input exceeds a first threshold and decouple the input from the output when the input falls below a second threshold. In particular, the passive switching circuit preferably comprises a spark gap, thyristor and avalanche diode, breakover diode, discharge tube, or a thyristor operated as breakover diodes. Circuits and dielectric elastomer generator (DEG) systems including the passive converter are also disclosed.