Abstract: Techniques, systems, and devices relating to conducting calibration of LIDAR systems are disclosed. In one exemplary aspect, a light detection and ranging (LIDAR) device is disclosed. The device comprises a light beam emitter operable to emit a light beam; a prism set positioned in an optical path of the light beam to refract the light beam onto a surface of a surrounding object; a light detector to detect light reflected by the surface of the surrounding object; a controller configured to estimate the surface of the surrounding object based on the detected light. The controller is operable to (1) determine a relative bias in the prism set, and (2) cause, based on the relative bias in the prism set, a compensation for an estimation error in the controller's estimation of the surface of the surrounding object.

Abstract: Hollow motor apparatuses and associated systems and methods for manufacturing hollow motor apparatuses may be provided. In one implementation, a hollow motor apparatus may include a rotor assembly rotatable about a rotation axis, a stator assembly positioned adjacent to, and coaxially with, the rotor assembly, and a bearing assembly configured to maintain a position of the rotor assembly relative to the stator assembly. The rotor assembly may include an inner portion disposed around an opening configured to receive and to rotate at least a portion of a payload. The bearing assembly may be disposed outside of the inner portion of the rotor assembly.

Abstract: A sensor system can comprise a light source configured to emit a light beam. Furthermore, the sensor system comprises one or more optical elements that is configured to homogenize the emitted light beam, which is directed toward a field of view (FOV) of the sensor system. Additionally, the sensor system comprises a detector with a plurality of photo detection devices, wherein each photo detection device of the plurality of photo detection devices is configured to receive at least a portion of photon energy of the light beam that is reflected back from one or more objects in the FOV of the sensor system and generate at least one electrical signal based on the received photon energy.

Abstract: Methods and systems for detecting and ranging an object may include or be configured to carry out the steps of emitting, by a laser light source, a first beam of light incident on a surface of the object, receiving, at an avalanche photodiode (APD) array, a second beam of light reflected from the surface of the object; reading, by a readout integrated circuit (ROIC) array, from the APD array; and processing, by the ROIC array, accumulated photocurrent from the APD array for outputting a signal representative of the object detected by the APD array.

Abstract: A sensor system can comprise a detector with a plurality of units, wherein the detector is configured to generate a first set of electrical signals based on received photon energy of a light beam that is reflected back from a first plurality of points on one or more objects, in a first configuration. Additionally, the detector is configured to generate a second set of electrical signals based on received photon energy of a light beam that is reflected back from a second plurality of points on one or more objects in a second configuration, wherein the first configuration and the second configuration are with a predetermined correlation. Furthermore, the detector can determine distance to each of the first plurality of points and the second plurality of points on the one or more objects based on the first set of electrical signals and the second set of electrical signals.

Abstract: A power adjustment method includes controlling a power detection circuit of a laser measurement device to detect a power of laser emitted from a laser emission circuit of the laser measurement device, obtaining a threshold power corresponding to the laser measurement device, and adjusting the power of the laser according to the threshold power.

Abstract: Introduced here are techniques for implementing a comparator-based LIDAR system with improved components, such as an improved high-speed comparator circuit, to acquire depth information from the surroundings of an unmanned moving object (e.g., a UAV). In various embodiments, the LIDAR system includes an amplifier module with different configurations of anti-saturation circuitry. The LIDAR system may further include various feedback control mechanisms for noise interference reduction and timing measurement compensation including, for example, dynamic gain adjustment of the photodetector module, and/or dynamic adjustment of comparators' thresholds. Among other components, the disclosed comparator circuit can provide the LIDAR system with a wide dynamic range, preventing large signal amplification saturation while also providing sufficient magnification of small signals.

Abstract: A method includes emitting an outbound light pulse by a light detection and ranging (LIDAR) device, and receiving a first light pulse and a second light pulse at the LIDAR device. The first light pulse is indicative of a reflection of the outbound light pulse by an internal part of the LIDAR device. The second light pulse is indicative of a reflection of the outbound light pulse by a surrounding object. The method further includes, responsive to an overlap between electronic signals representing the first and second light pulses, deriving an estimated time value associated with the second light pulse based on a piece of timing information in a trailing section of the second light pulse, and determining a distance of the surrounding object from the LIDAR device based on the estimated time value associated with the second light pulse.

Abstract: Representative embodiments of the present technology include a device for measuring distance to an object. The device comprises a light emitter configured to emit an outbound light pulse and a light sensor configured to receive a returning light pulse and output a pulse signal representing the returning light pulse. The device further comprises a field-programmable gate array (FPGA) coupled to the light sensor and including a time-to-digital converter (TDC) having a series of sequentially coupled delay units. Individual sequentially coupled delay units are associated with corresponding individual delay times. At least some of the sequentially coupled delay units have different individual delay times. The TDC is configured to measure timing information of the pulse signal based at least in part on the individual delay times of the sequentially coupled delay units. The device further includes a controller configured to calculate the distance to the object based on the timing information.

Abstract: A driving device includes two rotor assemblies, a stator assembly, and a positioning assembly. Each rotor assembly includes a rotation axis and a rotor. The rotor includes a hollow chamber. The two rotor assemblies include a first rotor assembly and a second rotor assembly, a rotation axis of the first rotor assembly is parallel with a rotation axis of the second rotor assembly, a rotor of the first rotor assembly is at least partially embedded in a chamber of a rotor of the second rotor assembly. The stator assembly is surroundingly disposed at an outer side of the two rotor assemblies and drives a rotor. The rotor driven by the stator assembly causes another rotor of one of the first rotor assembly and the second rotor assembly to rotate. The positioning assembly is located outside of the rotors, and limits the rotors to rotate around corresponding fixed rotation axes.

Abstract: Hollow motor apparatuses and associated systems and methods for manufacturing the same are disclosed herein. In representative embodiment, a hollow motor apparatus includes a rotor assembly rotatable about a rotation axis, a stator assembly positioned adjacent to the rotor assembly and coaxially with the rotor assembly relative to the rotation axis, and a bearing assembly operably coupled to the rotor assembly. The rotor assembly has an inner portion around an opening configured to receive at least a portion of a payload. The bearing assembly is disposed outside the inner portion of the rotor assembly and is configured to maintain a position of the rotor assembly relative to the stator assembly.

Abstract: A sensor system includes a light source, a plurality of optical elements, a controller, and a detector. The light source is configured to generate a series of light pulses at different time points. The optical elements rotate independently about rotation axes that are substantially aligned with each other. The controller is configured to control respective rotation of each of the plurality of optical elements, enabling the plurality of optical elements to collectively direct the series of light pulses toward different directions in an angle of view of the sensor system. The detector is configured to detect a plurality of target points in the angle of view. Each target point is detected based on receiving at least a portion of photon energy of a light pulse, from the series of light pulses, that is reflected back from one or more objects in the angle of view.

Abstract: Introduced here are techniques for implementing a comparator-based LIDAR system with improved components, such as an improved high-speed comparator circuit, to acquire depth information from the surroundings of an unmanned moving object (e.g., a UAV). In various embodiments, the LIDAR system includes an amplifier module with different configurations of anti-saturation circuitry. The LIDAR system may further include various feedback control mechanisms for noise interference reduction and timing measurement compensation including, for example, dynamic gain adjustment of the photodetector module, and/or dynamic adjustment of comparators' thresholds. Among other components, the disclosed comparator circuit can provide the LIDAR system with a wide dynamic range, preventing large signal amplification saturation while also providing sufficient magnification of small signals.

Abstract: A novel imaging system is provided for capturing imaging data. According to the disclosed embodiments, the imaging system comprises one or more cameras configured to capture the same scene within each camera's field of view. The imaging system also includes a plurality of bandpass filters that may be positioned in front of one or more cameras. Each bandpass filter may allow the transmission of incident electromagnetic signals between different pairs of first and second wavelengths. Accordingly, when the bandpass filters are positioned in front of the one or more cameras, each camera captures a different spectral image, i.e., containing only certain frequency components of the same scene being imaged in the cameras. The bandpass filters may be selectively aligned with one or more cameras by rotating and/or translating the filters relative to the cameras' positions in the imaging system.

Abstract: Techniques, systems, and devices relating to conducting calibration of LIDAR systems are disclosed. In one exemplary aspect, a light detection and ranging (LIDAR) device is disclosed. The device comprises a light beam emitter operable to emit a light beam; a prism set positioned in an optical path of the light beam to refract the light beam onto a surface of a surrounding object; a light detector to detect light reflected by the surface of the surrounding object; a controller configured to estimate the surface of the surrounding object based on the detected light. The controller is operable to (1) determine a relative bias in the prism set, and (2) cause, based on the relative bias in the prism set, a compensation for an estimation error in the controller's estimation of the surface of the surrounding object.

Abstract: Representative embodiments of the present technology include a device for measuring distance to an object. The device comprises a light emitter configured to emit an outbound light pulse and a light sensor configured to receive a returning light pulse and output a pulse signal representing the returning light pulse. The device further comprises a field-programmable gate array (FPGA) coupled to the light sensor and including a time-to-digital converter (TDC) having a series of sequentially coupled delay units. Individual sequentially coupled delay units are associated with corresponding individual delay times. At least some of the sequentially coupled delay units have different individual delay times. The TDC is configured to measure timing information of the pulse signal based at least in part on the individual delay times of the sequentially coupled delay units. The device further includes a controller configured to calculate the distance to the object based on the timing information.

Abstract: Techniques, systems, and devices relating to conducting calibration of LIDAR systems are disclosed. In one exemplary aspect, a light detection and ranging (LIDAR) device is disclosed. The device comprises a light beam emitter operable to emit a light beam; a prism set positioned in an optical path of the light beam to refract the light beam onto a surface of a surrounding object; a light detector to detect light reflected by the surface of the surrounding object; a controller configured to estimate the surface of the surrounding object based on the detected light. The controller is operable to (1) determine a relative bias in the prism set, and (2) cause, based on the relative bias in the prism set, a compensation for an estimation error in the controller's estimation of the surface of the surrounding object.

Abstract: Systems and methods for performing optical distance measurement are provided. In one aspect, a system for measuring a distance to an object comprises a light emitter configured to emit an outbound light pulse, and a light sensor configured to receive a returning light pulse reflected from the object and output an analog pulse signal representing the returning light pulse. The system also comprises a field-programmable gate array (FPGA) coupled to the light sensor. The FPGA is configured to convert the analog pulse signal to a plurality of digital signal values, and generate a plurality of time measurements corresponding to the plurality of digital signal values. The system also comprises a controller configured to calculate the distance to the object based on the plurality of digital signal values and the plurality of time measurements.

Abstract: Systems and methods for performing optical distance measurement are provided. In one aspect, a system for measuring a distance to an object comprises a light emitter configured to emit an outbound light pulse, and a light sensor configured to receive a returning light pulse reflected from the object and output an analog pulse signal representing the returning light pulse. The system also comprises a field-programmable gate array (FPGA) coupled to the light sensor. The FPGA is configured to convert the analog pulse signal to a plurality of digital signal values, and generate a plurality of time measurements corresponding to the plurality of digital signal values. The system also comprises a controller configured to calculate the distance to the object based on the plurality of digital signal values and the plurality of time measurements.

Abstract: Techniques, systems, and devices relating to conducting calibration of LIDAR systems are disclosed. In one exemplary aspect, a light detection and ranging (LIDAR) device is disclosed. The device comprises a light beam emitter operable to emit a light beam; a prism set positioned in an optical path of the light beam to refract the light beam onto a surface of a surrounding object; a light detector to detect light reflected by the surface of the surrounding object; a controller configured to estimate the surface of the surrounding object based on the detected light. The controller is operable to (1) determine a relative bias in the prism set, and (2) cause, based on the relative bias in the prism set, a compensation for an estimation error in the controller's estimation of the surface of the surrounding object.