Abstract: To dynamically control power in a lidar system, a controller identifies a triggering event and provides a control signal to a light source in the lidar system adjusting the power of light pulses emitted by the light source. The triggering event includes identifying a particular type of object within a threshold distance of the lidar system. In some scenarios, the power is adjusted to address eye-safety concerns.

Abstract: In one embodiment, a method for dynamically varying receiver characteristics in a lidar system includes emitting light pulses by a light source in a lidar system. The method further includes detecting, by a receiver in the lidar system, light from one of the light pulses scattered by one or more remote targets to identify a return light pulse. The method also includes determining an atmospheric condition at or near a geolocation of a vehicle that includes the lidar system. The method further includes providing a control signal to the receiver adjusting one or more characteristics of the receiver to compensate for attenuation or distortion of the return light pulses associated with the atmospheric condition.

Abstract: To dynamically control power in a lidar system, a controller identifies a triggering event and provides a control signal to a light source in the lidar system adjusting the power of light pulses provided by the light source. Triggering events may include exceeding a threshold speed, being within a threshold distance of a person or other object, an atmospheric condition, identifying residue on a surface of a window of the lidar system, etc. In some scenarios, the power is adjusted to address eye-safety concerns.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light. The emitted pulses of light include one or more series of standard-resolution pulses alternating with one or more series of high-resolution pulses. Each series of the standard-resolution pulses includes multiple pulses having a standard pulse period, and each series of the high-resolution pulses includes multiple pulses having a high-resolution pulse period. The standard pulse period is greater than or equal to a round-trip time associated with a maximum range of the lidar system, and the high-resolution pulse period is less than the standard pulse period. The lidar system also includes a scanner configured to scan at least a portion of the emitted pulses of light across a field of regard.

Abstract: To dynamically control power in a lidar system, a controller identifies a triggering event and provides a control signal to a light source in the lidar system adjusting the power of light pulses provided by the light source. Triggering events may include exceeding a threshold speed, being within a threshold distance of a person or other object, an atmospheric condition, identifying residue on a surface of a window of the lidar system, etc. In some scenarios, the power is adjusted to address eye-safety concerns.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light and a scanner configured to scan at least a portion of the emitted pulses of light along a scan pattern contained within an adjustable field of regard. The scanner includes a first scanning mirror configured to scan the portion of the emitted pulses of light substantially parallel to a first scan axis to produce multiple scan lines of the scan pattern. The scanner also includes a second scanning mirror configured to distribute the scan lines along a second scan axis, where the scan lines are distributed within the adjustable field of regard according to an adjustable second-axis scan profile that includes a minimum scan angle along the second scan axis, a maximum scan angle along the second scan axis, and a scan-line distribution.

Abstract: A computer-implemented method of determining relative velocity between a vehicle and an object. The method includes receiving sensor data generated by one or more sensors of the vehicle. The one or more sensors are configured to sense an environment through which the vehicle is moving by following a scan pattern comprising component scan lines. The method includes obtaining, by one or more processors, a point cloud frame based on the sensor data and representative of the environment and identifying, by the one or more processors, a point cloud object within the point cloud frame. The method further includes determining, by the one or more processors, that the point cloud object is skewed relative to an expected configuration of the point cloud object, and determining, by the one or more processors, a relative velocity of the point cloud object by analyzing the skew of the object.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light and a scanner configured to scan at least a portion of the emitted pulses of light across a field of regard. The field of regard contains all or part of a target located a distance from the lidar system that is less than or equal to a maximum range of the lidar system, and one or more of the emitted pulses of light are scattered by the target. The lidar system also includes a receiver configured to detect at least a portion of the pulses of light scattered by the target. The lidar system further includes a processor configured to determine the distance from the lidar system to the target based at least in part on a round-trip time of flight for an emitted pulse of light.

Abstract: To compensate for the uneven distribution of data points around the periphery of a vehicle in a lidar system, a light source transmits light pulses at a variable pulse rate according to the orientation of the light pulses with respect to the lidar system. A controller may communicate with a scanner in the lidar system that provides the orientations of the light pulses to the controller. The controller may then provide a control signal to the light source adjusting the pulse rate based on the orientations of the light pulses. For example, the pulse rate may be slower near the front of the lidar system and faster near the periphery. In another example, the pulse rate may be faster near the front of the lidar system and slower near the periphery.

Abstract: A method for determining a scan pattern according to which a sensor equipped with a scanner scans a field of regard (FOR) is presented. The method comprises obtaining, by processing hardware, a plurality of objective functions, each of the objective functions specifying a cost for a respective property of the scan pattern, expressed in terms of one or more operational parameters of the scanner. The method further includes applying, by the processing hardware, an optimization scheme to the plurality of objective functions to generate the scan pattern. The method further includes scanning the FOR according to the generated scan pattern.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light and a scanner configured to scan at least a portion of the emitted pulses of light along a scan pattern contained within an adjustable field of regard. The scanner includes a first scanning mirror configured to scan the portion of the emitted pulses of light substantially parallel to a first scan axis to produce multiple scan lines of the scan pattern, where each scan line is oriented substantially parallel to the first scan axis. The scanner also includes a second scanning mirror configured to distribute the scan lines along a second scan axis that is substantially orthogonal to the first scan axis, where the scan lines are distributed within the adjustable field of regard according to an adjustable second-axis scan profile.

Abstract: To dynamically control power in a lidar system, a controller identifies a triggering event and provides a control signal to a light source in the lidar system adjusting the power of light pulses provided by the light pulse. Triggering events may include exceeding a threshold speed, being within a threshold distance of a person or other object, an atmospheric condition, etc. In some scenarios, the power is adjusted to address eye-safety concerns.

Abstract: A method for processing point clouds having variable spatial distributions of scan lines includes receiving a point cloud frame generated by a sensor configured to sense an environment through which a vehicle is moving. The point cloud frame includes scan lines arranged according to a particular spatial distribution. The method also includes either generating an enhanced point cloud frame with a larger number of points than the received point cloud frame, or constructing, by one or more processors and based on points of the received point cloud frame, a three-dimensional mesh. The method also includes generating, by performing an interpolation function on the enhanced point cloud frame or a virtual surface provided by the three-dimensional mesh, a normalized point cloud frame, and generating, using the normalized point cloud frame, signals descriptive of a current state of the environment through which the vehicle is moving.

Abstract: A lidar system includes a transmitter that encodes successive transmit pulses with different pulse characteristics and a receiver that detects the pulse characteristics of each received (scattered or reflected) pulse and that distinguishes between the received pulses based on the detected pulse characteristics. The lidar system thus resolves range ambiguities by encoding pulses of scan positions in the same or different scan periods to have different pulse characteristics, such as different pulse widths or different pulse envelope shapes. The receiver includes a pulse decoder configured to detect the relevant pulse characteristics of the received pulse and a resolver that determines if the pulse characteristics of the received pulse matches the pulse characteristics of the current scan position or that of a previous scan position.

Abstract: A computer-implemented method of detecting object distortion. The method includes receiving sensor data generated by one or more sensors of the vehicle. The one or more sensors are configured to sense an environment through which the vehicle is moving by following a scan pattern. The method also includes obtaining, based on the sensor data, a point cloud frame representative of the environment and identifying a point cloud object within the point cloud frame. Additionally, the method includes analyzing the point cloud object to identify a feature of the point cloud object that has an expected shape and comparing the feature of the point cloud object to the expected shape. The method also includes identifying that the point cloud object is distorted based on the feature of the point cloud object not matching the expected shape.

Abstract: To decrease the likelihood of a false detection when detecting light from light pulses scattered by remote targets in a lidar system, a receiver in the lidar system includes a photodetector and a pulse-detection circuit having a gain circuit with a varying amount of gain over time. The gain circuit operates in a low-gain mode for a time period T1 beginning with time t0 when a light pulse is emitted to prevent the receiver from detecting return light pulses during the threshold time period T1. Upon expiration of the threshold time period T1, the gain circuit operates in a high-gain mode to begin detecting return light pulses until a subsequent light pulse is emitted.

Abstract: A method for controlling at least a first vehicle sensor includes receiving sensor data generated by one or more vehicle sensors that are configured to sense an environment through which the vehicle is moving, and identifying, based on the received sensor data, one or more current and/or predicted positions of one or more dynamic objects that are currently moving, or are capable of movement, within the environment. The method also includes causing, based on the current and/or predicted positions of the dynamic objects, an area of focus of the first sensor to be adjusted, at least by causing (i) a field of regard of the first sensor, and/or (ii) a spatial distribution of scan lines produced by the first sensor, to be adjusted.

Abstract: A lidar system comprises a light source configured to emit light, a scanner configured to direct the emitted light to scan a field of regard of the lidar system in accordance with a scan pattern, a receiver configured to detect the light scattered by one or more remote targets, and a controller configured to control motion of at least the second mirror to modify the scan pattern. The scanner includes a rotatable polygon mirror having a block having a first wall, a second wall, and reflective surfaces extending between the first and second walls, the reflective surfaces being angularly offset from one another along a periphery of the block. The scanner also includes a polygon mirror axle extending into the block through at least one of the first and second walls, about which the block rotates, and a second mirror pivotable along an axis orthogonal to the polygon mirror axle.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light and a scanner configured to scan at least a portion of the emitted pulses of light across a field of regard. The lidar system also includes a receiver configured to detect at least a portion of the scanned pulses of light scattered by a target located a distance from the lidar system.

Abstract: A computer-implemented method of detecting object distortion. The method includes receiving sensor data generated by one or more sensors of the vehicle. The one or more sensors are configured to sense an environment through which the vehicle is moving by following a scan pattern. The method also includes obtaining, based on the sensor data, a point cloud frame representative of the environment and identifying a point cloud object within the point cloud frame. Additionally, the method includes analyzing the point cloud object to identify a feature of the point cloud object that has an expected shape and comparing the feature of the point cloud object to the expected shape. The method also includes identifying that the point cloud object is distorted based on the feature of the point cloud object not matching the expected shape.