Eco-friendly energy harvesters with high output for effectively harvesting mechanical energy over a broad temperature range.

No abstract

A magnetorheological (MR) damper with energy harvesting ability was proposed based on electromagnetic induction (EMI) principle. The energy harvesting part was composed of a permanent magnet array and inducing coils which move vertically. This device could act as a linear power generator when the external excitation was applied, and the kinetic energy could be converted into electrical energy due to the relative linear motion between the magnets array and the inducing coils. Finite element models of both the MR damper part and the linear power generator part were built up separately to address the magnetic flux distributions, the magnetic flux densities, and the power generating efficiency using ANSYS software. The experimental tests were carried out to evaluate the damping performance and power generating efficiency. The results show that the proposed MR damper can produce approximately 750 N damping forces at the current of 0.6 A, and the energy harvesting device can generate about 1.0 V DC voltage at 0.06 m·s−1excitation.

No abstract

A magnetic field sensor is designed and fabricated using a piezoelectric face shear mode Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN–PT)/Metglas magneto-electric (ME) composite. An outstanding ME coupling coefficient up to 1600 V/(cm Oe) was experimentally achieved, being ∼50% higher than the value from the extensional PMN–PT/Metglas ME composite with the same volume. The detection limit was found to be 2 × 10−6 Oe for the DC magnetic field, while it was 2 × 10−8 Oe for the AC magnetic field. The sensitivity of the face shear mode PMN–PT/Metglas ME composite is about one order of magnitude higher than that of a 32 extensional mode PMN–PT/Metglas based ME composite in sensing a weak DC magnetic field. A sensing array was also designed based on the ME composite to image weak DC magnetic fields, demonstrating a great potential promising for sensing weak magnetic fields.