Generators for very-high-G energy harvesting

An energy harvesting device comprising:

• a housing having an internal cavity;
• an energy generating device arranged in the cavity;
• a mass-spring element having a mass and an elastic element and being operatively connected to the energy generating device upon an acceleration of the housing to produce an electrical power;
• and
• a biasing member for biasing the mass in a direction having at least a component in an acceleration direction of the housing
• wherein the biasing member is configured to deform upon an acceleration of the housing to preload the elastic element such that the mass-spring unit vibrates in the cavity after the acceleration ceases or diminishes.

An energy harvesting device comprising:

• a housing having a cavity;
• an energy generating device arranged in the cavity;
• a mass-spring unit having an elastic element and a mass, the mass being a free end of the elastic element and arranged to vibrate in a direction of an acceleration of the housing;
• wherein the elastic member includes one or more stops arranged in a longitudinal direction of the elastic member and the housing includes a support corresponding to each of the one or more stops so as to limit a longitudinal deflection of the one or more stops.

An energy harvesting device comprising:

• a housing having a cavity;
• an energy generating device arranged in the cavity;
• a mass-spring element having a mass and an elastic element and being operatively connected to the energy generating device upon an acceleration of the housing to produce an electrical power;
• and
• a spacer arranged in the cavity, the spacer having a first position so as to limit a vibration of the mass-spring unit and a second position permitting the mass-spring unit to vibrate, the spacer being movable from the first position to the second position due to an acceleration of the housing.

A method for harvesting energy from a high-G acceleration of a munition, the method comprising:

• proving a vibrating mass-spring unit in a housing of an energy harvesting device;
• and
• reducing an effective acceleration on the mass-spring unit by one or more of:
• offsetting the vibration of the mass-spring unit with respect to a direction of the high-G acceleration;
• biasing a mass of the mass-spring unit in a direction having at least a component in the direction of the high-G acceleration;
• limiting a vibration deflection of at least a portion of the mass-spring unit in the direction of the high-G acceleration;
• or
• limiting an amount of vibration of the mass-spring unit in a direction offset from the direction of the high-G acceleration and removing such limit after the acceleration.