Abstract: In one general aspect, an apparatus can include a first laser subsystem configured to transmit a first laser beam at a first location on an object at a time and a second laser subsystem configured to transmit a second laser beam at a second location on the object at the time. The apparatus can include an analyzer configured to calculate a first velocity based on a first reflected laser beam reflected from the object in response to the first laser beam. The analyzer can be configured to calculate a second velocity based on a second reflected laser beam reflected from the object in response to the second laser beam. The first location can be targeted by the first laser subsystem and the second location can be targeted by the second laser subsystem such that the first velocity is substantially the same as the second velocity.

Abstract: Techniques of measuring vibrations from an object surface using LIDAR includes grouping beams having similar vibration velocity values over a specified time window and replace outlier vibration velocity values with a vibration velocity value based on the similar vibration velocity values over the specified time window. Advantageously, replacing outlier vibration velocity values with a value based on vibration velocity values of similar beams results in a more accurate profile of the vibration velocity field over the surface.

Abstract: Techniques of deriving audio signals using frequency modulated continuous-wave (FMCW) LIDAR use an acceleration-based algorithm in which an audio signal is based on a difference in velocity between two up-chirps or two-down-chirps. Such an acceleration-based algorithm takes less computation, results in fast processing, boosts the high frequency component of the audio signals which the velocity-based algorithm lacks, and improves the subjective intelligibility. For example, in the acceleration-based algorithm, the DC components may be safely ignored in many cases. In such cases, the system does not require a band-pass filter as in the conventional systems, thus reducing computational burden. Moreover, the acceleration-based algorithm emphasizes high frequencies that form a more realistic depiction of human speech.

Abstract: A remote tracking system such as a LIDAR system may track objects such as human faces. In such objects there is a natural axis of symmetry that is seen to be substantially normal to the orientation of the object. Nevertheless, because the object is typically in motion, one cannot expect that beams incident on the object to be normal to the object consistently. Rather, the beams tend to dwell on the object at some skew angle. In a typical case, the detected beam pattern from a given portion of the object is dependent on this dwell angle. In conventional remote tracking systems, it may be difficult to identify the portion of the object efficiently through all of the possible beam patterns due to variation of the dwell angle. It is an objective of improved techniques described herein to efficiently monitor and track an object regardless of the dwell angle.

Abstract: In one general aspect, a non-transitory computer-readable storage medium can be configured to store instructions that when executed cause a processor to perform a process. The process can include transmitting a plurality of laser beams at a feature on an object, and calculating a candidate shape parameter representing the feature based on a plurality of laser beams reflected from the feature. The process can include determining that the candidate shape parameter matches a measured shape parameter stored in a shape parameter database and representing a measured feature of the object, and identifying an absolute location corresponding with the measured feature of the object.

Abstract: A laser microphone can include a detection system including plurality of laser subsystems. The detection system can be configured to produce emitted electromagnetic radiation based on a frequency pattern and receive reflected electromagnetic radiation reflected from an object. The detection system can be configured to define combined frequency data based on a frequency of the emitted, electromagnetic radiation and a frequency of the reflected electromagnetic radiation. The detection system can be configured to define a set of spectral bins in a frequency domain based on the combined frequency data, modify the combined frequency data based on a datapoint obtained from a subset of the set of spectral bins, and define at least one of a range or a velocity based on the combined frequency data. The laser microphone can include an audio processor configured to define an audio signal based on the at least one of the range or velocity.

Abstract: In one general aspect, a system for determining a motion of an object includes a laser system configured to generate range and velocity measurements of a plurality of points on the object and a processor. The processor is configured to determine, from the range and velocity measurements of the plurality of points on the object, a rotation of the object. In some aspects, the processor is also configured to determine, from the range and velocity measurements of the plurality of points on the object and the rotation of the object, a distance moved by the object between a first time and a second time.

Abstract: Techniques of tracking an object involve a Light Detection And Ranging (LIDAR) system. The LIDAR system can be configured to track an object over a period of time, during which the object is moving. Using the LIDAR system tracking of the object can be performed while eliminating illumination hardware (e.g., video camera hardware). Accordingly, the LIDAR system can be configured to operate in total darkness, into the sun, etc. The LIDAR system can be less susceptible to motion of the object than conventional systems. Accordingly, the full rigid-body motion of the object can be determined in some implementations solely from LIDAR measurements, without, for example, video.

Abstract: Techniques of tracking an object's motion involve using a LIDAR system that is configured to track an object over a period of time in which the object is moving using a single scanning motion. Using the LIDAR system, tracking of the object can be performed while eliminating visible imaging hardware (e.g., video camera hardware). Accordingly, the LIDAR system can be configured to operate in total darkness, into the sun, etc. The LIDAR system can be less susceptible to motion of the object than conventional systems. Accordingly, the motion of the object 110 be determined in some implementations solely from LIDAR measurements, without, for example, video.

Abstract: In one general aspect, an apparatus can include a first laser subsystem configured to transmit a first laser beam at a first location on an object at a time and a second laser subsystem configured to transmit a second laser beam at a second location on the object at the time. The apparatus can include an analyzer configured to calculate a first velocity based on a first reflected laser beam reflected from the object in response to the first laser beam. The analyzer can be configured to calculate a second velocity based on a second reflected laser beam reflected from the object in response to the second laser beam. The first location can be targeted by the first laser subsystem and the second location can be targeted by the second laser subsystem such that the first velocity is substantially the same as the second velocity.

Abstract: In one general aspect, a non-transitory computer-readable storage medium storing instructions that when executed cause one or more processors to perform a process. The process can include producing emitted electromagnetic radiation based on a frequency pattern and receiving reflected electromagnetic radiation reflected from an object. The process can include defining combined frequency data based on a frequency of the emitted electromagnetic radiation and a frequency of the reflected electromagnetic radiation. The process can also include defining a set of spectral bins, based on a Fourier transform, in a frequency domain based on the combined frequency data, and can include identifying a subset of the set of spectral bins.

Abstract: In one general aspect, a non-transitory computer-readable storage medium can be configured to store instructions that when executed cause a processor to perform a process. The process can include producing a segment of a laser signal where the segment of the laser signal has a duration, and producing a first reference signal based on the laser signal. The process can include calculating a first phase deviation corresponding with a first portion of the duration based on the first reference signal, and producing a second reference signal based on the laser signal. The process can include calculating a second phase deviation corresponding with a second portion of the duration based on the second reference signal, and calculating a phase deviation of the segment of the laser signal based on a combination of the first phase deviation and the second phase deviation.

Abstract: In one general aspect, a system for determining a motion of an object includes a laser system configured to generate range and velocity measurements of a plurality of points on the object and a processor. The processor is configured to determine, from the range and velocity measurements of the plurality of points on the object, a rotation of the object. In some aspects, the processor is also configured to determine, from the range and velocity measurements of the plurality of points on the object and the rotation of the object, a distance moved by the object between a first time and a second time.

Abstract: A laser microphone can include a detection system including plurality of laser subsystems. The detection system can be configured to produce emitted electromagnetic radiation based on a frequency pattern and receive reflected electromagnetic radiation reflected from an object. The detection system can be configured to define combined frequency data based on a frequency of the emitted, electromagnetic radiation and a frequency of the reflected electromagnetic radiation. The detection system can be configured to define a set of spectral bins in a frequency domain based on the combined frequency data, modify the combined frequency data based on a datapoint obtained from a subset of the set of spectral bins, and define at least one of a range or a velocity based on the combined frequency data. The laser microphone can include an audio processor configured to define an audio signal based on the at least one of the range or velocity.

Abstract: In one general aspect, a non-transitory computer-readable storage medium storing instructions that when executed cause one or more processors to perform a process. The process can include producing emitted electromagnetic radiation based on a frequency pattern and receiving reflected electromagnetic radiation reflected from an object. The process can include defining combined frequency data based on a frequency of the emitted electromagnetic radiation and a frequency of the reflected electromagnetic radiation. The process can also include defining a set of spectral bins, based on a Fourier transform, in a frequency domain based on the combined frequency data, and can include identifying a subset of the set of spectral bins.