Zoox, Inc.

Panosense Inc.

Denis Nikitin

Ryan McMichael

Adam Berger

Brian Pilnick

Riley Andrews

Subasingha Shaminda Subasingha

Turhan Karadeniz

Brian Alexander Pesch

Robert Nicholas Moor

Harrison Thomas Waschura

Ravi Sankar Mahankali

Joseph Patrick Warga

Mehran Ferdowsi

Silas Kogure Wilkinson

Arthur Benemann

Joshua Franz

A LIDAR system emits laser bursts, wherein each burst has at least a pair of pulses. The pulses of each pair are spaced by a time interval having a variable duration to reduce effects of cross-talk. For example, certain embodiments may have multiple emitter/sensor channels that are used sequentially, and each channel may use a different duration for inter-pulse spacing to reduce the effects of cross-talk between channels. The durations may also be varied over time. The emitters and sensors are physically arranged in a two-dimensional array to achieve a relatively fine vertical pitch. The array has staggered rows that are packed using a hexagonal packing arrangement. The channels are used in a sequential order that is selected to maximize spacing between consecutively used channels, further reducing possibilities for inter-channel cross-talk.

Lidar system

Sensors, including time-of-flight sensors, may be used to detect objects in an environment. In an example, a vehicle may include a time-of-flight sensor that images objects around the vehicle, e.g., so the vehicle can navigate relative to the objects. Sensor data generated by the time-of-flight sensor can be impacted by glare. In some examples, an emitter system for illuminating a field of view can be dynamically altered to provide different illumination intensities at different regions in the field of view. For instance, locations at which a highly-reflective object or other object that is likely to cause glare may be illuminated at a lower illumination intensity, e.g., to reduce the likelihood of pixel saturation in measured data associated with the object.

Dynamic sensor illumination

Sensors, including time-of-flight sensors, may be used to detect objects in an environment. In an example, a vehicle may include a time-of-flight sensor that images objects around the vehicle, e.g., so the vehicle can navigate relative to the objects. Sensor data generated by the time-of-flight sensor can return unreliable pixels, e.g., in the case of over-exposure or saturation. In some examples, multiple exposures captured at different exposure times can be used to determine an overall saturation value or metric representative of the sensor data. The saturation value may be used to control parameters of the sensor. For instance, the saturation value may be used to determine power control parameters for the sensor, e.g., to reduce over- and/or under-exposure.

Power control of sensors using multiple exposures

A LIDAR sensor assembly includes a laser light source to emit laser light, and a light sensor to produce a light signal in response to sensing reflections of the laser light emitted by the laser light source from a reference surface that is fixed in relation to the LIDAR sensor assembly. A controller of the LIDAR sensor assembly can process a plurality of samples of reflected light signals, process the samples to remove erroneous readings, and then provide accurate distance measurement. The system can use low-pass filters, or other components, to filter the plurality of samples to enable the 'actual,' or primary, reflected light signal (i.e., light signal reflected off of a surface in an environment external to the sensor assembly, as opposed to extraneous, internal reflections off of lenses or other components or noise) to be identified and an accurate time of flight to be calculated.

LIDAR ring lens return filtering

Sensors, including time-of-flight sensors, may be used to detect objects in an environment. In an example, a vehicle may include a time-of-flight sensor that images objects around the vehicle, e.g., so the vehicle can navigate relative to the objects. Sensor data generated by the time-of-flight sensor can return pixels subject to over-exposure or saturation, which may be from stray light. In some examples, multiple exposures captured at different exposure times can be used to determine a saturation value for sensor data. The saturation value may be used to determine a threshold intensity against which intensity values of a primary exposure are compared. A filtered data set can be obtained based on the comparison.

Pixel filtering using multiple exposures

A lidar photosensor amplification circuit may include light sensors; amplifiers corresponding respectively to the light sensors, in a powered-on state, to amplify output signals of the respective light sensors as amplified outputs; and switches corresponding respectively to the amplifiers, where individual switches may be controlled to pass a respective amplified output in a closed state or disconnect the amplified output in an open state. The lidar photosensor amplification circuit may be controlled by a controller according to timing rules that conserve power supplied to photosensor amplification circuit, reduce heat produced by the light sensor board, and do not aggravate cross-talk between sensors. The timing rules include staging an amplifier for a staging time before the corresponding light sensor is to be read, closing a switch after the staging time has passed, and powering down the amplifier and opening the switch after a reading time passes.

Lidar photosensor amplification circuit

Sensors, including time-of-flight sensors, may be used to detect objects in an environment. In an example, a vehicle may include a time-of-flight sensor that images objects around the vehicle, e.g., so the vehicle can navigate relative to the objects. Sensor data generated by the time-of-flight sensor can return unreliable pixels, e.g., in the case of over- or under-exposure. In some examples, parameters associated with power of a time-of-flight sensor can be altered based on a number of unreliable pixels in measured data and/or based on intensity values of the measured data. For example, unreliable pixels can be determined using phase frame information captured at a receiver of the sensor.

Active power control of sensors

A LIDAR system includes one or more LIDAR sensor assemblies, which may be mounted to a vehicle or other object. Each LIDAR sensor assembly includes a laser light source to emit laser light, and a light sensor to produce a light signal in response to sensing reflected light corresponding to reflection of the laser light emitted by the laser light source from a reference surface that is fixed in relation to the LIDAR sensor assembly. A controller of the LIDAR sensor assembly may calibrate the LIDAR sensor assembly based at least in part on a signal from the light sensor indicating detection of reflected light corresponding to reflection of a pulse of laser light reflected from the reference surface.

LIDAR sensor assembly calibration based on reference surface

Techniques are described for aligning optical components within a LIDAR assembly. The techniques may be performed to align the optical components during manufacturing or assembly of the LIDAR assembly. For example, a first optical element (e.g., one of a light source or light sensor) may be installed in the LIDAR assembly. An optimal alignment for a second optical element (e.g., the other of the light source or light sensor) may be determined and the second optical element may be installed at the optimal alignment. The optimal alignment for the second optical element may be determined based on detected signals, for example, which may correspond to an alignment resulting in a strongest return signal, highest quality return signal, and/or minimal interference. Additionally or alternatively, techniques may be used to align optical components at runtime by using an actuator to move one or more components of the LIDAR assembly during operation.

Aligning optical components in LIDAR systems

A LIDAR system emits laser pulses, wherein each pulse is associated with a power level. A laser emitter is adjusted during operation of a LIDAR system using power profile data associated with the laser. The power profile data is obtained during a calibration procedure and includes information that associates charge duration for a laser power supply with the actual power output by laser. The power profiles can be used during operation of the LIDAR system. A laser pulse can be emitted, the reflected light from the pulse received and analyzed, and the power of the next pulse can be adjusted based on a lookup within the power profile for the laser. For instance, if the power returned from a pulse is too high (e.g., above some specified threshold), the power of the next pulse is reduced to a specific value based on the power profile.

Laser power cailibration and correction

Lidar ring lens return filtering

Sensors, including time-of-flight sensors, may be used to detect objects in an environment. In an example, a vehicle may include a time-of-flight sensor that images objects around the vehicle, e.g., so the vehicle can navigate relative to the objects. The sensor may generate first image data at a first configuration and second image data at a second configuration. The first image data and the second image data may be combined to provide disambiguated depth and improved intensity values for imaging the environment. In some examples, the first and second configurations may have different modulation frequencies, different integration times, and/or different illumination intensities. In some examples, configurations may be dynamically altered based on depth and/or intensity information of a previous frame.

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Campbell, CA, United States of America

Denis Nikitin