Abstract: A self-learning method for an obstacle and a self-learning method for a new obstacle are provided. With the self-learning method, in step 1, data of a grid map in a movement region is acquired, and each of grids of the grid map is marked as not being traversed. In step 2, a starting grid of the grid map is set, data of the starting grid is pushed into a stack, a movement unit is controlled to move to the starting grid, and the starting grid is remarked as being traversed. In step 3, the movement unit is controlled to traverse the grid map, and boundary data of the obstacle is acquired based on marks of the grids in the grid map. In step 4, boundary data of the obstacle is stored.

Abstract: A four-level rectifier may include an output, a first capacitor, a second capacitor, a third capacitor, and three phases. The first, second, and third capacitors may be connected in series. The output may be connected between the first capacitor and the third capacitor. Each of the three phases may include an input, a first diode, a second diode, a first switch, a second switch, and a third switch. The first diode may be connected between the input and the first capacitor. The second diode may be connected between the input and the third capacitor. The first switch may be connected between the input and the second switch and the third switch. The second switch may be connected to the first capacitor and to the second capacitor. The third switch may be connected to the second capacitor and to the third capacitor.

Abstract: An exemplary system includes an inverter coupled to a DC source, eight power switches and three DC-link capacitors that synthesize seven output voltage levels. In one example the inverter includes a four-level active neutral pointed clamped inverter (4L-ANCP) that includes six power switches of the eight power switches is operated at a switching frequency with a first voltage stress level, and a half-bridge that includes the other two of the eight power switches is coupled to the 4L-ANCP and operated at a fundamental frequency with a second voltage stress, the second voltage stress being higher than the first voltage stress level.

Abstract: A boost or DC-DC converter includes a first output and a second output, a first inductor having a first side and a second side, the first side of the first inductor being connectable in electrical communication with a first output of a power supply or DC voltage source, and a second inductor having a first side and a second side, the first side of the second inductor being connectable in electrical communication with the first output of the power supply, the first inductor being inversely coupled to the second inductor. The converter includes a first switch in communication with the second side of the first inductor and a second output of the power supply, and a second switch in communication with the second side of the second inductor and the second output of the power supply.

Abstract: A multi-port power conversion system can have a multi-winding transformer and at least three ports. Each port can be coupled to the multi-winding transformer. Each port can have a semiconductor bridge and a coupling network. For each port, the semiconductor bridge can have two or more levels and can comprise at least two switches. The coupling network for each port can comprise at least one inductor. The semiconductor bridge can be coupled to the multi-winding transformer via the respective coupling network. The multi-port power conversion system can have a multi-active bridge (MAB) architecture that is universally applicable to AC-DC, DC-DC, DC-AC, and AC-AC conversion applications and extendable to any number of ports.

Abstract: A method of camera control for a camera capturing images of a target includes a sequence of at least four steps. The first step determines in real time a location of a drone and a pose of a camera on the drone. The second step, which may occur before or after the first step, determines in real time a location of a reference object, the location of the reference object having a fixed relationship to a location of the target. The third step uses the determined locations to calculate a distance, characterized by magnitude and direction, between the target and the drone. The fourth step uses the calculated distance to control the pose of the camera such that an image captured by the camera includes the target. Controlling the pose of the camera does not require any analysis of the captured image.

Abstract: A four-level rectifier may include an output, a first capacitor, a second capacitor, a third capacitor, and three phases. The first, second, and third capacitors may be connected in series. The output may be connected between the first capacitor and the third capacitor. Each of the three phases may include an input, a first diode, a second diode, a first switch, a second switch, and a third switch. The first diode may be connected between the input and the first capacitor. The second diode may be connected between the input and the third capacitor. The first switch may be connected between the input and the second switch and the third switch. The second switch may be connected to the first capacitor and to the second capacitor. The third switch may be connected to the second capacitor and to the third capacitor.

Abstract: A method of camera control for a camera capturing images of a target includes a sequence of at least four steps. The first step determines in real time a location of a drone and a pose of a camera on the drone. The second step, which may occur before or after the first step, determines in real time a location of a reference object, the location of the reference object having a fixed relationship to a location of the target. The third step uses the determined locations to calculate a distance, characterized by magnitude and direction, between the target and the drone. The fourth step uses the calculated distance to control the pose of the camera such that an image captured by the camera includes the target. Controlling the pose of the camera does not require any analysis of the captured image.

Abstract: A method and system for generating inverted electrical signals includes a first string of batteries connected in series, each battery having a half-bridge circuit connected in parallel and each having upper switch and lower switches. A first H-bridge circuit is connected in parallel with the first string of batteries, and a triangle wave generator generates a plurality of triangle wave signals at a given amplitude and carrier frequency. The plurality of triangle wave signals have individual triangle wave signals phase-shifted from one another. A modulation wave generator generates a modulation signal at a modulation amplitude and at twice a fundamental frequency that is less than the carrier frequency. A controller compares an instantaneous magnitude of the individual triangle wave signals to an instantaneous magnitude of the modulation signal, and outputs commands to the upper switch of a respective half-bridge circuit based on the comparison.

Abstract: A method and system for generating inverted electrical signals includes a first string of batteries connected in series, each battery having a half-bridge circuit connected in parallel and each having upper switch and lower switches. A first H-bridge circuit is connected in parallel with the first string of batteries, and a triangle wave generator generates a plurality of triangle wave signals at a given amplitude and carrier frequency. The plurality of triangle wave signals have individual triangle wave signals phase-shifted from one another. A modulation wave generator generates a modulation signal at a modulation amplitude and at twice a fundamental frequency that is less than the carrier frequency. A controller compares an instantaneous magnitude of the individual triangle wave signals to an instantaneous magnitude of the modulation signal, and outputs commands to the upper switch of a respective half-bridge circuit based on the comparison.

Abstract: A laser pump cavity includes a heat sink holder with a central through hole, a plurality of slot portions, and a plurality of single emitters. The single emitter includes a heat sink and a single core disposed on the heat sink. The slot portions are uniformly spaced and surround the through hole. The single emitters are connected end to end, thereby forming at least one single emitter array. The at least one single emitter array is disposed in corresponding slot portions with each single core facing the through hole.