Patents by Inventor Anand Gopalan

Anand Gopalan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11294041
    Abstract: Described herein are systems and methods for improving detection of a return signal in a light ranging and detection system. The system comprises a transmitter and a receiver. A first sequence of pulses may be encoded with an anti-spoof signature and transmitted in a laser beam. A return signal, comprising a second sequence of pulses, may be received by the receiver and the anti-spoof signature extracted from the second sequence of pulses. If based on the extraction, the first and second sequences of pulses match, the receiver outputs return signal data. If based on the extraction, the first and second sequence of pulses do not match, the return signal is disregarded. The system may dynamically change the anti-spoofing signature for subsequent sequences of pulses. Additionally, the first sequence of pulses may be randomized relative to a prior sequence of pulses.
    Type: Grant
    Filed: December 8, 2017
    Date of Patent: April 5, 2022
    Assignee: VELODYNE LIDAR USA, INC.
    Inventors: David S. Hall, Anand Gopalan
  • Publication number: 20220075038
    Abstract: A LiDAR system includes an optical transmitter, a scanner, a segmented optical detector including discrete sense nodes distributed along its length, and a controller. The optical transmitter can transmit a ranging signal via an optical component of the scanner. The scanner can change a position and/or orientation of the optical component after the ranging signal is transmitted. The segmented optical detector can receive the return signal corresponding to the ranging signal via the optical component after the change in the position and/or orientation of the optical component. The controller can detect a location of a return spot of the return signal based on outputs of the discrete sense nodes. The controller can determine a distance to an object that reflected the return signal based on the location of the return spot and a residual time of flight of the return signal.
    Type: Application
    Filed: September 9, 2021
    Publication date: March 10, 2022
    Inventors: David S. Hall, Mathew Rekow, Nikhil Naikal, Sunil Khatana, Stephen S. Nestinger, Anand Gopalan
  • Publication number: 20220057510
    Abstract: Apparatus and methods for aligning circuit boards (e.g., for LIDAR systems) are disclosed. According to one embodiment, an electronic device comprises a secondary device and a coupling device coupled to the secondary device. The coupling device comprises a plurality of conductive members, including a first conductive member and a second conductive member. Each of the conductive members comprises a first end configured to electrically and mechanically couple to a primary circuit board and a second end electrically and mechanically coupled to the secondary device. Each of the plurality of conductive members has an attribute adjustable in response to a condition being added to the respective conductive member, and is configured to maintain the adjusted attribute after the condition is removed.
    Type: Application
    Filed: November 8, 2021
    Publication date: February 24, 2022
    Inventors: David S. Hall, Anand Gopalan, Cristhian Octavio Reyes, Thomas Richardson Tewell, Mathew Noel Rekow
  • Patent number: 11255728
    Abstract: Described herein are systems and methods that may efficiently detect multi-return light signals. A light detection and ranging system, such as a LiDAR system, may fire a laser beam that may hit multiple objects with a different distance in one line, causing multi-return light signals to be received by the system. Multi-return detectors may be able to analyze the peak magnitude of a plurality of peaks in the return signals and determine a multitude of peaks, such as the first peak, the last peak and the maximum peak. One embodiment to detect the multi-return light signals may be a multi-return recursive matched filter detector. This detector comprises a matched filter, peak detector, centroid calculation and a zeroing out function. Other embodiments may be based on a maximum finder that algorithmically selects the highest magnitude peaks from samples of the return signal and buffers for regions of interests peaks.
    Type: Grant
    Filed: June 23, 2020
    Date of Patent: February 22, 2022
    Assignee: VELODYNE LIDAR USA, INC.
    Inventors: Kiran Kumar Gunnam, Kanke Gao, Nitinkumar Sagarbhai Barot, Anand Gopalan, David S. Hall
  • Publication number: 20220035031
    Abstract: Ultrasonic ranging systems and methods that emit coded bursts and correlate transduced acoustical echoes of the bursts with a receive template characterizing a burst code to determine time-of-flight information use receive templates of time-variable length to improve short-range object detection. The template length is based on a time index measured from the start of the burst emission. The detection can account for a dead zone of transducer ringing following a burst. A time-variable gain that is also based on the time index can be applied to the correlated signal. The length and gain can be adjusted with reduced temporal frequency to reduce computation cost.
    Type: Application
    Filed: October 18, 2021
    Publication date: February 3, 2022
    Inventors: LEI DING, SRINATH MATHUR RAMASWAMY, ANAND GOPALAN
  • Publication number: 20210364609
    Abstract: A scanner of a LiDAR system includes a mirror configured to redirect a light signal emitted by an optical emitter, a first axis scanning system configured to rotate the mirror about a first axis and with respect to the optical emitter, that controls a first angle of emission of the light signal from the LiDAR system into a field of view of the LiDAR system, and a second axis scanning system configured to rotate the mirror about a second axis and with respect to the optical emitter, that controls a second angle of emission of the light signal from the LiDAR system into the field of view. The first axis scanning mechanism is configured to rotate the reflective surface of the mirror at least 45 degrees about the first axis.
    Type: Application
    Filed: August 2, 2021
    Publication date: November 25, 2021
    Inventors: David S. Hall, Andrew Janik, Mathew Noel Rekow, Anand Gopalan, Stephen S. Nestinger, William B. Etheridge
  • Patent number: 11175402
    Abstract: Ultrasonic ranging systems and methods that emit coded bursts and correlate transduced acoustical echoes of the bursts with a receive template characterizing a burst code to determine time-of-flight information use receive templates of time-variable length to improve short-range object detection. The template length is based on a time index measured from the start of the burst emission. The detection can account for a dead zone of transducer ringing following a burst. A time-variable gain that is also based on the time index can be applied to the correlated signal. The length and gain can be adjusted with reduced temporal frequency to reduce computation cost.
    Type: Grant
    Filed: November 25, 2019
    Date of Patent: November 16, 2021
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Lei Ding, Srinath Mathur Ramaswamy, Anand Gopalan
  • Patent number: 11169267
    Abstract: Apparatus and methods for aligning circuit boards (e.g., for LIDAR systems) are disclosed. According to one embodiment, an electronic device comprises a secondary device and a coupling device coupled to the secondary device. The coupling device comprises a plurality of conductive members, including a first conductive member and a second conductive member. Each of the conductive members comprises a first end configured to electrically and mechanically couple to a primary circuit board and a second end electrically and mechanically coupled to the secondary device. The second end of the first conductive member is coupled to a first side of the secondary device, and the second end of the second conductive member is coupled to a second side of the secondary device. The second side of the secondary device is opposite to the first side of the secondary device.
    Type: Grant
    Filed: May 22, 2020
    Date of Patent: November 9, 2021
    Assignee: VELODYNE LIDAR USA, INC.
    Inventors: David S. Hall, Anand Gopalan, Cristhian Octavio Reyes, Thomas Richardson Tewell, Mathew Noel Rekow
  • Publication number: 20210156995
    Abstract: Ultrasonic ranging systems and methods that emit coded bursts and correlate transduced acoustical echoes of the bursts with a receive template characterizing a burst code to determine time-of-flight information use receive templates of time-variable length to improve short-range object detection. The template length is based on a time index measured from the start of the burst emission. The detection can account for a dead zone of transducer ringing following a burst. A time-variable gain that is also based on the time index can be applied to the correlated signal. The length and gain can be adjusted with reduced temporal frequency to reduce computation cost.
    Type: Application
    Filed: November 25, 2019
    Publication date: May 27, 2021
    Inventors: LEI DING, SRINATH MATHUR RAMASWAMY, ANAND GOPALAN
  • Publication number: 20200379094
    Abstract: Methods and systems for combining return signals from multiple channels of a LIDAR measurement system are described herein. In one aspect, the outputs of multiple receive channels are electrically coupled before input to a single channel of an analog to digital converter. In another aspect, a DC offset voltage is provided at the output of each transimpedance amplifier of each receive channel to improve measured signal quality. In another aspect, a bias voltage supplied to each photodetector of each receive channel is adjusted based on measured temperature to save power and improve measurement consistency. In another aspect, a bias voltage supplied to each illumination source of each transmit channel is adjusted based on measured temperature. In another aspect, a multiplexer is employed to multiplex multiple sets of output signals of corresponding sets of receive channels before analog to digital conversion.
    Type: Application
    Filed: August 6, 2020
    Publication date: December 3, 2020
    Inventors: David S. Hall, Rajanatha Shettigara, Nathan Slattengren, Aaron Chen, Anand Gopalan
  • Publication number: 20200379117
    Abstract: Apparatus and methods for aligning circuit boards (e.g., for LIDAR systems) are disclosed. According to one embodiment, an electronic device comprises a secondary device and a coupling device coupled to the secondary device. The coupling device comprises a plurality of conductive members, including a first conductive member and a second conductive member. Each of the conductive members comprises a first end configured to electrically and mechanically couple to a primary circuit board and a second end electrically and mechanically coupled to the secondary device. The second end of the first conductive member is coupled to a first side of the secondary device, and the second end of the second conductive member is coupled to a second side of the secondary device. The second side of the secondary device is opposite to the first side of the secondary device.
    Type: Application
    Filed: May 22, 2020
    Publication date: December 3, 2020
    Inventors: David S. Hall, Anand Gopalan, Cristhian Octavio Reyes, Thomas Richardson Tewell, Mathew Rekow
  • Publication number: 20200348401
    Abstract: Described herein are systems and methods for improving detection of a return signal in a light ranging and detection system. The system comprises a transmitter and a receiver. A first sequence of pulses may be encoded with an anti-spoof signature and transmitted in a laser beam. A return signal, comprising a second sequence of pulses, may be received by the receiver and the anti-spoof signature extracted from the second sequence of pulses. If based on the extraction, the first and second sequences of pulses match, the receiver outputs return signal data. If based on the extraction, the first and second sequence of pulses do not match, the return signal is disregarded. The system may dynamically change the anti-spoofing signature for subsequent sequences of pulses. Additionally, the first sequence of pulses may be randomized relative to a prior sequence of pulses.
    Type: Application
    Filed: July 16, 2020
    Publication date: November 5, 2020
    Inventors: David S. Hall, Anand Gopalan
  • Publication number: 20200319338
    Abstract: Described herein are systems and methods that may efficiently detect multi-return light signals. A light detection and ranging system, such as a LiDAR system, may fire a laser beam that may hit multiple objects with a different distance in one line, causing multi-return light signals to be received by the system. Multi-return detectors may be able to analyze the peak magnitude of a plurality of peaks in the return signals and determine a multitude of peaks, such as the first peak, the last peak and the maximum peak. One embodiment to detect the multi-return light signals may be a multi-return recursive matched filter detector. This detector comprises a matched filter, peak detector, centroid calculation and a zeroing out function. Other embodiments may be based on a maximum finder that algorithmically selects the highest magnitude peaks from samples of the return signal and buffers for regions of interests peaks.
    Type: Application
    Filed: June 23, 2020
    Publication date: October 8, 2020
    Inventors: Kiran Kumar Gunnam, Kanke Gao, Nitinkumar Sagarbhai Barot, Anand Gopalan, David S. Hall
  • Publication number: 20200309945
    Abstract: Ultrasonic sensing systems and associated methods provide side-lobe reduction to improve the acoustic detection of small objects, the signature envelope peaks of which can otherwise be obscured by subsidiary envelope peaks in side lobes that result from residual correlation between a signal received by an ultrasonic transducer and a template signal corresponding to a burst signal emitted by the ultrasonic transducer. A shaping signal by which the amplitude of the burst signal can be varied with respect to time is taken into account in the template signal, and correlator circuitry correlates a signal derived from the ultrasonic transducer with the template signal to produce a correlated output exhibiting the desired side-lobe reduction. The distance from the transducer to the detected object can thereby be determined with enhanced accuracy and responsiveness.
    Type: Application
    Filed: March 26, 2019
    Publication date: October 1, 2020
    Inventors: LEI DING, SRINATH MATHUR RAMASWAMY, ANAND GOPALAN, MICHAEL JOHN ZROKA
  • Patent number: 10739444
    Abstract: Methods and systems for combining return signals from multiple channels of a LIDAR measurement system are described herein. In one aspect, the outputs of multiple receive channels are electrically coupled before input to a single channel of an analog to digital converter. In another aspect, a DC offset voltage is provided at the output of each transimpedance amplifier of each receive channel to improve measured signal quality. In another aspect, a bias voltage supplied to each photodetector of each receive channel is adjusted based on measured temperature to save power and improve measurement consistency. In another aspect, a bias voltage supplied to each illumination source of each transmit channel is adjusted based on measured temperature. In another aspect, a multiplexer is employed to multiplex multiple sets of output signals of corresponding sets of receive channels before analog to digital conversion.
    Type: Grant
    Filed: September 18, 2018
    Date of Patent: August 11, 2020
    Assignee: VELODYNE LIDAR, INC.
    Inventors: David S. Hall, Rajanatha Shettigara, Nathan Slattengren, Aaron Chen, Anand Gopalan
  • Publication number: 20200225345
    Abstract: Ultrasonic ranging systems and methods that use coding to distinguish emitted bursts from multiple transducers temporally stagger the bursts emitted from the transducers. The stagger delay between bursts from different transducers in a sensing frame can be randomized between different sensing frames to prevent blind zones. The stagger delay can be relatively small (e.g., between 3 ms and 10 ms) as compared to delays required between bursts in a single-tone ranging system (which would need to be more on the order of between 30 ms and 40 ms, depending on the maximum detecting range of the ranging system). The coding of bursts can be selected to utilize the entire bandwidth of the bursting transducer so as to preserve short-range sensitivity over transducer ringing. Schemes in which some transducers in a system only listen for bursts from other transducers but do not themselves burst within a sensing frame are also described.
    Type: Application
    Filed: May 30, 2019
    Publication date: July 16, 2020
    Inventors: LEI DING, Srinath Mathur Ramaswamy, Anand Gopalan, Vaibhav Garg, Anand Ganesh Dabak
  • Publication number: 20200217959
    Abstract: The present disclosure relates generally to systems and methods for configuring architectures for a sensor, and more particularly for light detection and ranging (hereinafter, “LIDAR”) systems based on ASIC sensor architectures supporting autonomous navigation systems. Effective ASIC sensor architecture can enable an improved correlation between sensor data as well as configurability and responsiveness of the system to its surrounding environment and avoid any unnecessary delay within the decision-making process that may result in a failure of the autonomous driving system. It may be essential to integrated multiple functions within an electronic module and implement the functionality with one or more ASICs.
    Type: Application
    Filed: January 7, 2019
    Publication date: July 9, 2020
    Applicant: Velodyne LiDAR, Inc.
    Inventors: David HALL, Anand GOPALAN, Matthew REKOW, Pravin Kumar VENKATESAN
  • Publication number: 20200218062
    Abstract: Described herein are systems and methods that implement a dual axis resonant scanning mirror to support a sensor system such as a LIDAR system. The scanning mirror may comprise: 1) a small dual axis mirror, in which each axis is moving by similar electromagnetic mechanisms can generate crosstalk between each of these electromagnetic mechanisms causing perturbations in the motion; 2) a primary axis that may need to be driven independently of the motion of a secondary axis and vice versa; 3) an optical position sensor; 4) a scanning mirror assembly that may be mounted to a scanner base via the secondary axis. The scanning mirror assembly may comprise resonant spring, resonant spring assembly, the rocking chair (with electromagnetic drive coils), the scanner base with a set of two secondary axis propulsion magnets, the mirror with a spacer and primary axis propulsion magnets, and the optical sense board.
    Type: Application
    Filed: January 7, 2019
    Publication date: July 9, 2020
    Applicant: Velodyne LiDAR, Inc.
    Inventors: David HALL, Anand GOPALAN, Matthew REKOW, Garrett ROGREN
  • Publication number: 20200217954
    Abstract: The present disclosure relates generally to systems and methods for generating, processing and correlating data from multiple sensors in an autonomous navigation system, and more particularly to the utilization of configurable and dynamic sensor modules within light detection and ranging systems that enable an improved correlation between sensor data as well as configurability and responsiveness of the system to its surrounding environment.
    Type: Application
    Filed: January 7, 2019
    Publication date: July 9, 2020
    Applicant: Velodyne LiDAR, Inc.
    Inventors: David HALL, Anand GOPALAN, Matthew REKOW, Stephen NESTINGER, Tyler BANAS
  • Publication number: 20200218260
    Abstract: The present disclosure relates generally to systems and methods for generating, processing and correlating data from multiple sensors in an autonomous navigation system, and more particularly to the utilization of configurable and dynamic sensor modules within light detection and ranging systems that enable an improved correlation between sensor data as well as configurability and responsiveness of the system to its surrounding environment.
    Type: Application
    Filed: January 7, 2019
    Publication date: July 9, 2020
    Applicant: Velodyne LiDAR, Inc.
    Inventors: DAVID HALL, ANAND GOPALAN, MATTHEW REKOW, VISHAL JAIN