Abstract: A spring (3, 3?) comprising a plurality of elements (30), each element (3) comprising a rigid portion (31) and a flexible beam (32), the extremities (320, 321) of the flexible beam being supported by the rigid portion (31), the flexible beam (32) having a single stable position, so that the flexible beam can be deformed when a pressure is exerted between said extremities in the direction of the rigid portion (31), and returns to said single stable position when the pressure is released, and wherein the rigid portion (31) of at least one element (30) is in contact with the flexible beam (32) of the next element between said extremities (320, 321) of the flexible beam (32), so that the spring has a negative stiffness over an operating range. The arrangement ensures a pure radial compression/expansion of the spring.

Abstract: The present invention is related to a stretchable tubular device (1) comprising at least one layer (Lx) of a stretchable polymer, a power supply (2) and a set of electrodes (3a, 3b) connected to said power supply (2). The power supply can supply at least a first level of voltage (V1) to the electrodes so as to modify the natural force (F0) of the stretchable layers to a modified force (F1). The present invention also covers a process for manufacturing such a tubular device and its use as a medical implant.

Abstract: A dielectric elastomer actuator comprising: a plurality of polymer layer; a plurality of stretchable electrode layers, each polymer layer being sandwiched between two electrode layers so as to control the electric field within the polymer layer; at least one stretchable charge distribution layer, each charge distribution layer being adjacent to one stretchable electrode layer and/or to one polymer layer.

Abstract: A spring (3, 3?) comprising a plurality of elements (30), each element (3) comprising a rigid portion (31) and a flexible beam (32), the extremities (320, 321) of the flexible beam being supported by the rigid portion (31), the flexible beam (32) having a single stable position, so that the flexible beam can be deformed when a pressure is exerted between said extremities in the direction of the rigid portion (31), and returns to said single stable position when the pressure is released, and wherein the rigid portion (31) of at least one element (30) is in contact with the flexible beam (32) of the next element between said extremities (320, 321) of the flexible beam (32), so that the spring has a negative stiffness over an operating range. The arrangement ensures a pure radial compression/expansion of the spring.

Abstract: The present disclosure relates to a method of adjusting the resonance frequency of a vibrating element, comprising measuring the resonance frequency of the vibrating element, determining, using abacuses and as a function of the resonance frequency measured, a dimension and a position of at least one area of modified thickness to be formed on the vibrating element so that the resonance frequency thereof corresponds to a setpoint frequency, and forming on the vibrating element, an area of modified thickness of the determined dimension and position.

Abstract: The present disclosure relates to a method of adjusting the resonance frequency of a vibrating element, comprising measuring the resonance frequency of the vibrating element, determining, using abacuses and as a function of the resonance frequency measured, a dimension and a position of at least one area of modified thickness to be formed on the vibrating element so that the resonance frequency thereof corresponds to a setpoint frequency, and forming on the vibrating element, an area of modified thickness of the determined dimension and position.