Abstract: A system that includes a power transmitting antenna (124) with a coiled conductor defined by a first axis and a second axis perpendicular to the first axis, where a single plane comprises the first axis and the second axis. The system includes a support layer (140, 142) comprising: a substantially planar top surface and a substantially planar bottom surface opposite the substantially planar top surface arranged parallel to the plane. The support layer also comprises a material with a predetermined resiliency. The support layer is configured to support a mass of a user and maintain a predetermined spacing between the plane of the power transmitting antenna and the user during compression of the material from the mass of the user.

Abstract: A charging device is described. One example of a charging device described herein includes at least one coil contained in a housing, where the at least one coil wirelessly transfers energy to an implantable medical device. The charging device may further include a coil manipulator that adjusts a configuration of the at least one coil within the housing.

Abstract: Devices, systems, and techniques are described to detect when a power transmitting and receiving system is in an inefficient position, which may cause a thermal response that less desirable than a more efficient position. The system may power transmitting device configured to wirelessly transfer electromagnetic energy to a power receiving device. Processing circuitry of the system may compute a target output power deliverable by the power transmitting device for a first duration and control the power transmitting device to output the target output power based in part on a heat limit. The processing circuitry may further calculate an energy transfer efficiency to the power receiving unit, update an adjustment factor based on the calculated energy transfer efficiency, and apply the adjustment factor to the heat limit for a subsequent duration.

Abstract: A charging device includes a coil configured to wirelessly transfer energy to an implantable medical device. The charging device includes a phase change material. The charging device may include a ground plane. The phase change material is incorporated in the charging device, and a flexibility of the charging device is associated with a state of the phase change material. The ground plane is conformable to one or more surfaces of a target subject. The charging device may include a heat reduction assembly. The heat reduction assembly includes a material disposed in contact with the coil. The phase change material absorbs at least a portion of heat generated by the coil.

Abstract: Devices, systems, and techniques are described to detect when a power transmitting and receiving system is in an inefficient position, which may cause a thermal response that less desirable than a more efficient position. The system may power transmitting device configured to wirelessly transfer electromagnetic energy to a power receiving device. Processing circuitry of the system may compute a target output power deliverable by the power transmitting device for a first duration and control the power transmitting device to output the target output power based in part on a heat limit. The processing circuitry may further calculate an energy transfer efficiency to the power receiving unit, update an adjustment factor based on the calculated energy transfer efficiency, and apply the adjustment factor to the heat limit for a subsequent duration.

Abstract: A wireless power transfer system in which the driver and control circuitry are located within the electromagnetic field of the power transmission antenna, e.g., a charging coil. The power transfer system may be contained in a flexible housing, which change shape using one or more hinges, be formed of a conformable material and so on. Changes in the relative location of the antenna and the circuitry may cause interference in the circuitry and loading of the antenna, which in turn may impact the electromagnetic field output by the antenna. The wireless power system may include sensors that provide an indication of an amount of deformation of the system. The driver circuitry of this disclosure may receive an indication of the relative location of the circuitry to the antenna and compensate for changes in the output electromagnetic field caused by changes in the relative location.

Abstract: The disclosure describes techniques to provide antennae configured to harvest radio-frequency (RF) energy from the nearby environment to provide electrical energy to an electrically powered device. Antennae may be configured in different shapes, lengths, locations, and materials to efficiently collect RF energy to be converted to electrical power. In some examples, RF energy may be harvested from existing sources, such as FM radio transmissions, communication transmissions such as Wi-Fi and BLUETOOTH, and similar existing sources. In other examples, antennae may be configured to collect energy from a source specifically designated to recharge the device. In some examples, the harvested RF energy may be sufficient to power the device. In other examples, the harvested RF energy may provide enough power to reduce the amount of recharging required by other means, such as by inductive recharging.

Abstract: Devices, systems, and techniques are described to detect when a power transmitting and receiving system is in an inefficient position, which may cause a thermal response that less desirable than a more efficient position. The system may power transmitting device configured to wirelessly transfer electromagnetic energy to a power receiving device. Processing circuitry of the system may compute a target output power deliverable by the power transmitting device for a first duration and control the power transmitting device to output the target output power based in part on a heat limit. The processing circuitry may further calculate an energy transfer efficiency to the power receiving unit, update an adjustment factor based on the calculated energy transfer efficiency, and apply the adjustment factor to the heat limit for a subsequent duration.

Abstract: Devices, systems, and techniques are described to provide consistent power transfer from a power transmitting unit to power receiving unit. In an example of recharging an electrical energy storage device, e.g., a battery, consistent power transfer may result in consistent recharge durations. A system may include a training mode in which a user may change a location of the power transfer unit relative to the power receiving unit. The system may provide an output to the user with a relative for a consistent power transfer. In other examples, a power transfer system may include a learning algorithm that measures and stores the power transfer during power transfer for a number of sessions over time. The learning algorithm may provide an output to a user of a relative location and/or relative orientation of the power transfer unit and power receiving unit that provides a consistent power transfer.

Abstract: The disclosure describes techniques to provide antennae configured to harvest radio-frequency (RF) energy from the nearby environment to provide electrical energy to an electrically powered device. Antennae may be configured in different shapes, lengths, locations, and materials to efficiently collect RF energy to be converted to electrical power. In some examples, RF energy may be harvested from existing sources, such as FM radio transmissions, communication transmissions such as Wi-Fi and BLUETOOTH, and similar existing sources. In other examples, antennae may be configured to collect energy from a source specifically designated to recharge the device. In some examples, the harvested RF energy may be sufficient to power the device. In other examples, the harvested RF energy may provide enough power to reduce the amount of recharging required by other means, such as by inductive recharging.