Karl Berntorp

Karl Berntorp
  • Biography

    Karl's research interests include statistical signal processing, Bayesian inference and learning, sensor fusion, and optimization-based control, with applications to automotive, transportation, navigation, positioning, and communication systems. Karl is an Associate Editor and member of the IEEE Technology Conferences Editorial Board.

  • Recent News & Events


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  • Awards

    •  AWARD    Best Student Paper Award at the IEEE Conference on Control Technology and Applications
      Date: August 26, 2020
      Awarded to: Marcus Greiff, Anders Robertsson, Karl Berntorp
      MERL Contacts: Karl Berntorp; Marcus Greiff
      Research Areas: Control, Signal Processing
      Brief
      • Marcus Greiff, a former MERL intern from the Department of Automatic Control, Lund University, Sweden, won one of three 2020 CCTA Outstanding Student Paper Awards and the Best Student Paper Award at the 2020 IEEE Conference on Control Technology and Applications. The research leading up to the awarded paper titled 'MSE-Optimal Measurement Dimension Reduction in Gaussian Filtering', concerned how to select a reduced set of measurements in estimation applications while minimally degrading performance, was done in collaboration with Karl Berntorp at MERL.
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  • Internships with Karl

    • CA1944: Vehicle Estimation and Learning

      MERL is seeking a highly motivated and qualified intern to collaborate with the Control for Autonomy team in research on GNSS-based estimation and sensor fusion algorithms. The ideal candidate is expected to be working towards a PhD with strong emphasis in statistical signal processing and estimation, and with experience in at least some of the following areas: application and theory of Bayesian inference, learning, Kalman filters, variational Bayes, automotive, autonomous vehicles, distributed estimation, large-scale estimation, sensor fusion including camera radar and/or GNSS. Good programming skills in MATLAB, Python, or C/C++ are required. The expected duration of the internship is 3-6 months.

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  • MERL Publications

    •  Vaskov, S., Quirynen, R., Menner, M., Berntorp, K., "Friction-Adaptive Stochastic Nonlinear Model Predictive Control for Autonomous Vehicles", Vehicle System Dynamics, May 2023.
      BibTeX TR2023-064 PDF
      • @article{Vaskov2023may2,
      • author = {Vaskov, Sean and Quirynen, Rien and Menner, Marcel and Berntorp, Karl},
      • title = {Friction-Adaptive Stochastic Nonlinear Model Predictive Control for Autonomous Vehicles},
      • journal = {Vehicle System Dynamics},
      • year = 2023,
      • month = may,
      • url = {https://www.merl.com/publications/TR2023-064}
      • }
    •  You, S., Greiff, M., Quirynen, R., Ran, S., Wang, Y., Berntorp, K., Dai, R., Di Cairano, S., "Integral Action NMPC for Tight Maneuvers of Articulated Vehicles", American Control Conference (ACC), May 2023.
      BibTeX TR2023-058 PDF
      • @inproceedings{You2023may,
      • author = {You, Sixiong and Greiff, Marcus and Quirynen, Rien and Ran, Shuangxuan and Wang, Yebin and Berntorp, Karl and Dai, Ran and Di Cairano, Stefano},
      • title = {Integral Action NMPC for Tight Maneuvers of Articulated Vehicles},
      • booktitle = {American Control Conference (ACC)},
      • year = 2023,
      • month = may,
      • url = {https://www.merl.com/publications/TR2023-058}
      • }
    •  Menner, M., Berntorp, K., "Gaussian Processes with State-Dependent Noise for Stochastic Control", arXiv, May 2023.
      BibTeX arXiv
      • @article{Menner2023may,
      • author = {Menner, Marcel and Berntorp, Karl},
      • title = {Gaussian Processes with State-Dependent Noise for Stochastic Control},
      • journal = {arXiv},
      • year = 2023,
      • month = may,
      • url = {https://arxiv.org/abs/2305.16229}
      • }
    •  Menner, M., Berntorp, K., Di Cairano, S., "Automated Controller Calibration by Kalman Filtering", IEEE Transactions on Control Systems Technology, April 2023.
      BibTeX TR2023-022 PDF
      • @article{Menner2023apr,
      • author = {Menner, Marcel and Berntorp, Karl and Di Cairano, Stefano},
      • title = {Automated Controller Calibration by Kalman Filtering},
      • journal = {IEEE Transactions on Control Systems Technology},
      • year = 2023,
      • month = apr,
      • url = {https://www.merl.com/publications/TR2023-022}
      • }
    •  Chakrabarty, A., Berntorp, K., Di Cairano, S., "Parameter-Adaptive Reference Governors with Learned Robust Constraint-Admissible Sets", Control Engineering Practice, DOI: 10.1016/​j.conengprac.2023.105450, Vol. 133, February 2023.
      BibTeX TR2023-005 PDF
      • @article{Chakrabarty2023feb,
      • author = {Chakrabarty, Ankush and Berntorp, Karl and Di Cairano, Stefano},
      • title = {Parameter-Adaptive Reference Governors with Learned Robust Constraint-Admissible Sets},
      • journal = {Control Engineering Practice},
      • year = 2023,
      • volume = 133,
      • month = feb,
      • doi = {10.1016/j.conengprac.2023.105450},
      • url = {https://www.merl.com/publications/TR2023-005}
      • }
    See All Publications for Karl
  • Other Publications

    •  K. Berntorp, "Joint Wheel-Slip and Vehicle-Motion Estimation Based on Inertial, GPS, and Wheel-Speed Sensors", IEEE Transactions on Control Systems Technology, Vol. 24, No. 3, pp. 1020-1027, May 2016.
      BibTeX
      • @Article{7247687,
      • author = {K. Berntorp},
      • title = {Joint Wheel-Slip and Vehicle-Motion Estimation Based on Inertial, GPS, and Wheel-Speed Sensors},
      • journal = {IEEE Transactions on Control Systems Technology},
      • year = 2016,
      • volume = 24,
      • number = 3,
      • pages = {1020--1027},
      • month = may
      • }
    •  Karl Berntorp, "Particle Filter for Combined Wheel-Slip and Vehicle-Motion Estimation", 2015 American Control Conference, July 2015.
      BibTeX
      • @Inproceedings{berntorp2015acc,
      • author = {Berntorp, Karl},
      • title = {Particle Filter for Combined Wheel-Slip and Vehicle-Motion Estimation},
      • booktitle = {2015 American Control Conference},
      • year = 2015,
      • address = {Chicago, IL},
      • month = jul
      • }
    •  Karl Berntorp and Fredrik Magnusson, "Hierarchical Predictive Control for Ground-Vehicle Maneuvering", 2015 American Control Conference, July 2015.
      BibTeX
      • @Inproceedings{berntorp_magnusson2015acc,
      • author = {Berntorp, Karl and Magnusson, Fredrik},
      • title = {Hierarchical Predictive Control for Ground-Vehicle Maneuvering},
      • booktitle = {2015 American Control Conference},
      • year = 2015,
      • address = {Chicago, IL},
      • month = jul
      • }
    •  Bjorn Olofsson, Karl Berntorp and Anders Robertsson, "A Convex Approach to Path Tracking with Obstacle Avoidance for Pseudo-Omnidirectional Vehicles," Tech. Rep., Department of Automatic Control, Lund University, Sweden, 2015.
      BibTeX
      • @Techreport{8232521,
      • author = {Olofsson, Bjorn and Berntorp, Karl and Robertsson, Anders},
      • title = {A Convex Approach to Path Tracking with Obstacle Avoidance for Pseudo-Omnidirectional Vehicles},
      • institution = {Department of Automatic Control, Lund University, Sweden},
      • year = 2015
      • }
    •  Karl Berntorp and Jerker Nordh, "Rao-Blackwellized Particle Smoothing for Occupancy-Grid Based SLAM Using Low-Cost Sensors", 19th IFAC World Congress, August 2014.
      BibTeX
      • @Inproceedings{bern_jnifacwc,
      • author = {Berntorp, Karl and Nordh, Jerker},
      • title = {Rao-Blackwellized Particle Smoothing for Occupancy-Grid Based SLAM Using Low-Cost Sensors},
      • booktitle = {19th IFAC World Congress},
      • year = 2014,
      • address = {Cape Town, South Africa},
      • month = aug
      • }
    •  Kristoffer Lundahl, Bjorn Olofsson, Karl Berntorp, Jan Aslund and Lars Nielsen, "Towards Lane-Keeping Electronic Stability Control for Road-Vehicles", 19th IFAC World Congress, August 2014.
      BibTeX
      • @Inproceedings{lundahl_etal2013ifacwc,
      • author = {Lundahl, Kristoffer and Olofsson, Bjorn and Berntorp, Karl and {\AA}slund, Jan and Nielsen, Lars},
      • title = {Towards Lane-Keeping Electronic Stability Control for Road-Vehicles},
      • booktitle = {19th IFAC World Congress},
      • year = 2014,
      • address = {Cape Town, South Africa},
      • month = aug
      • }
    •  Karl Berntorp, Bjorn Olofsson and Anders Robertsson, "Path Tracking with Obstacle Avoidance for Pseudo-Omnidirectional Mobile Robots Using Convex Optimization", 2014 American Control Conference, June 2014.
      BibTeX
      • @Inproceedings{bern_etal2014acc,
      • author = {Berntorp, Karl and Olofsson, Bjorn and Robertsson, Anders},
      • title = {Path Tracking with Obstacle Avoidance for Pseudo-Omnidirectional Mobile Robots Using Convex Optimization},
      • booktitle = {2014 American Control Conference},
      • year = 2014,
      • address = {Portland, Oregon},
      • month = jun
      • }
    •  Karl Berntorp, "Particle Filtering and Optimal Control for Vehicles and Robots", May 2014, Department of Automatic Control, Lund University, Sweden.
      BibTeX
      • @Phdthesis{berntorp2014phd,
      • author = {Berntorp, Karl},
      • title = {Particle Filtering and Optimal Control for Vehicles and Robots},
      • school = {Department of Automatic Control, Lund University, Sweden},
      • year = 2014,
      • month = may
      • }
    •  Fredrik Magnusson, Karl Berntorp, Bjorn Olofsson and Johan Akesson, "Symbolic Transformations of Dynamic Optimization Problems", 10th International Modelica Conference, March 2014.
      BibTeX
      • @Inproceedings{magn_eal2014modelica,
      • author = {Magnusson, Fredrik and Berntorp, Karl and Olofsson, Bjorn and {\AA}kesson, Johan},
      • title = {Symbolic Transformations of Dynamic Optimization Problems},
      • booktitle = {10th International Modelica Conference},
      • year = 2014,
      • address = {Lund, Sweden},
      • month = mar
      • }
    •  Karl Berntorp, Anders Robertsson and Karl-Erik Arzen, "Rao-Blackwellized Particle Filters with Out-of-Sequence Measurement Processing", IEEE Transactions on Signal Processing, Vol. 62, No. 24, pp. 6454-6467, 2014.
      BibTeX
      • @Article{bernieeesp,
      • author = {Berntorp, Karl and Robertsson, Anders and Arzen, Karl-Erik},
      • title = {Rao-Blackwellized Particle Filters with Out-of-Sequence Measurement Processing},
      • journal = {IEEE Transactions on Signal Processing},
      • year = 2014,
      • volume = 62,
      • number = 24,
      • pages = {6454--6467}
      • }
    •  Karl Berntorp, Bjorn Olofsson, Kristoffer Lundahl and Lars Nielsen, "Models and methodology for optimal trajectory generation in safety-critical road–vehicle manoeuvres", Vehicle System Dynamics, Vol. 52, No. 10, pp. 1304-1332, 2014.
      BibTeX
      • @Article{bernvsd,
      • author = {Berntorp, Karl and Olofsson, Bjorn and Lundahl, Kristoffer and Nielsen, Lars},
      • title = {Models and methodology for optimal trajectory generation in safety-critical road–vehicle manoeuvres},
      • journal = {Vehicle System Dynamics},
      • year = 2014,
      • volume = 52,
      • number = 10,
      • pages = {1304--1332}
      • }
    •  Bjorn Olofsson, Kristoffer Lundahl, Karl Berntorp and Lars Nielsen, "An Investigation of Optimal Vehicle Maneuvers for Different Road Conditions", 7th IFAC Symposium on Advances in Automotive Control, September 2013.
      BibTeX
      • @Inproceedings{olof_etal2013aac,
      • author = {Olofsson, Bjorn and Lundahl, Kristoffer and Berntorp, Karl and Nielsen, Lars},
      • title = {An Investigation of Optimal Vehicle Maneuvers for Different Road Conditions},
      • booktitle = {7th IFAC Symposium on Advances in Automotive Control},
      • year = 2013,
      • address = {Tokyo, Japan},
      • month = sep
      • }
    •  Kristoffer Lundahl, Karl Berntorp, Bjorn Olofsson, Jan Aslund and Lars Nielsen, "Studying the Influence of Roll and Pitch Dynamics in Optimal Road-Vehicle Maneuvers", 23rd International Symposium on Dynamics of Vehicles on Roads and Tracks, August 2013.
      BibTeX
      • @Inproceedings{lund_etal2013iavsd,
      • author = {Lundahl, Kristoffer and Berntorp, Karl and Olofsson, Bjorn and {\AA}slund, Jan and Nielsen, Lars},
      • title = {Studying the Influence of Roll and Pitch Dynamics in Optimal Road-Vehicle Maneuvers},
      • booktitle = {23rd International Symposium on Dynamics of Vehicles on Roads and Tracks},
      • year = 2013,
      • address = {Qingdao, China},
      • month = aug
      • }
    •  Karl Berntorp, Anders Robertsson and Karl-Erik Arzen, "Rao-Blackwellized Out-of-Sequence Processing for Mixed Linear/Nonlinear State-Space Models", 16th International Conference on Information Fusion, July 2013.
      BibTeX
      • @Inproceedings{bern_etal2013fusion,
      • author = {Berntorp, Karl and Robertsson, Anders and Arzen, Karl-Erik},
      • title = {Rao-Blackwellized Out-of-Sequence Processing for Mixed Linear/Nonlinear State-Space Models},
      • booktitle = {16th International Conference on Information Fusion},
      • year = 2013,
      • address = {Istanbul, Turkey},
      • month = jul
      • }
    •  Karl Berntorp, Bjorn Olofsson, Kristoffer Lundahl, Bo Bernhardsson and Lars Nielsen, "Models and Methodology for Optimal Vehicle Maneuvers Applied to a Hairpin Turn", 2013 American Control Conference, June 2013.
      BibTeX
      • @Inproceedings{bern_etal2012acc,
      • author = {Berntorp, Karl and Olofsson, Bjorn and Lundahl, Kristoffer and Bernhardsson, Bo and Nielsen, Lars},
      • title = {Models and Methodology for Optimal Vehicle Maneuvers Applied to a Hairpin Turn},
      • booktitle = {2013 American Control Conference},
      • year = 2013,
      • address = {Washington, DC},
      • month = jun
      • }
    •  Jerker Nordh and Karl Berntorp, "pyParticleEst -- A Python Framework for Particle Based Estimation," Tech. Rep., Department of Automatic Control, Lund University, Sweden, March 2013.
      BibTeX
      • @Techreport{bern_7628,
      • author = {Nordh, Jerker and Berntorp, Karl},
      • title = {pyParticleEst -- A Python Framework for Particle Based Estimation},
      • institution = {Department of Automatic Control, Lund University, Sweden},
      • year = 2013,
      • month = mar
      • }
    •  Karl Berntorp, "Derivation of a Six Degrees-of-Freedom Ground-Vehicle Model for Automotive Applications," Tech. Rep., Department of Automatic Control, Lund University, Sweden, February 2013.
      BibTeX
      • @Techreport{bern_7627,
      • author = {Berntorp, Karl},
      • title = {Derivation of a Six Degrees-of-Freedom Ground-Vehicle Model for Automotive Applications},
      • institution = {Department of Automatic Control, Lund University, Sweden},
      • year = 2013,
      • month = feb
      • }
    •  Karl Berntorp, Karl-Erik Arzen and Anders Robertsson, "Mobile Manipulation with a Kinematically Redundant Manipulator for a Pick-and-Place Scenario", 2012 IEEE Multi-Conference on Systems and Control, October 2012.
      BibTeX
      • @Inproceedings{bern_etal2012ieeemsc,
      • author = {Berntorp, Karl and Arzen, Karl-Erik and Robertsson, Anders},
      • title = {Mobile Manipulation with a Kinematically Redundant Manipulator for a Pick-and-Place Scenario},
      • booktitle = {2012 IEEE Multi-Conference on Systems and Control},
      • year = 2012,
      • address = {Dubrovnik, Croatia},
      • month = oct
      • }
    •  Jerker Nordh and Karl Berntorp, "Extending the Occupancy Grid Concept for Low-Cost Sensor Based SLAM", 10th International IFAC Symposium on Robot Control, September 2012.
      BibTeX
      • @Inproceedings{nordh_bern2012SYROCO,
      • author = {Nordh, Jerker and Berntorp, Karl},
      • title = {Extending the Occupancy Grid Concept for Low-Cost Sensor Based SLAM},
      • booktitle = {10th International IFAC Symposium on Robot Control},
      • year = 2012,
      • address = {Dubrovnik, Croatia},
      • month = sep
      • }
    •  Karl Berntorp, Karl-Erik Arzen and Anders Robertsson, "Storage Efficient Particle Filters with Multiple Out-of-Sequence Measurements", 15th International Conference on Information Fusion, July 2012.
      BibTeX
      • @Inproceedings{bern_etal2012fusion,
      • author = {Berntorp, Karl and Arzen, Karl-Erik and Robertsson, Anders},
      • title = {Storage Efficient Particle Filters with Multiple Out-of-Sequence Measurements},
      • booktitle = {15th International Conference on Information Fusion},
      • year = 2012,
      • address = {Singapore},
      • month = jul
      • }
    •  Karl Berntorp, Karl-Erik Arzen and Anders Robertsson, "Sensor Fusion for Motion Estimation of Mobile Robots with Compensation for Out-of-Sequence Measurements", 11th International Conference on Control, Automation and Systems, October 2011.
      BibTeX
      • @Inproceedings{bern_etal2011ccas,
      • author = {Berntorp, Karl and Arzen, Karl-Erik and Robertsson, Anders},
      • title = {Sensor Fusion for Motion Estimation of Mobile Robots with Compensation for Out-of-Sequence Measurements},
      • booktitle = {11th International Conference on Control, Automation and Systems},
      • year = 2011,
      • address = {Gyeonggi-do, Korea},
      • month = oct
      • }
    •  Karl Berntorp, "ESP for Suppression of Jackknifing in an Articulated Bus," Tech. Rep., Department of Automatic Control, Lund University, Sweden, December 2008.
      BibTeX
      • @Techreport{bern_5831,
      • author = {Berntorp, Karl},
      • title = {ESP for Suppression of Jackknifing in an Articulated Bus},
      • institution = {Department of Automatic Control, Lund University, Sweden},
      • year = 2008,
      • month = dec
      • }
  • Videos

  • MERL Issued Patents

    • Title: "Probabilistic state tracking with multi-head measurement model"
      Inventors: Berntorp, Karl; Greiff, Marcus; Di Cairano, Stefano; Kim, Kyeong-Jin
      Patent No.: 11,644,579
      Issue Date: May 9, 2023
    • Title: "System and Method for Tracking Expanded State of an Object"
      Inventors: Wang, Pu; Xia, Yuxuan; Berntorp, Karl; Koike-Akino, Toshiaki; Mansour, Hassan; Boufounos, Petros T.; Orlik, Philip V.
      Patent No.: 11,619,494
      Issue Date: Apr 4, 2023
    • Title: "System and Method for Determining Friction Curve of Tire"
      Inventors: Berntorp, Karl
      Patent No.: 11,597,364
      Issue Date: Mar 7, 2023
    • Title: "Model-Based Control Under Uncertainty"
      Inventors: Berntorp, Karl; Di Cairano, Stefano
      Patent No.: 11,501,193
      Issue Date: Nov 15, 2022
    • Title: "Model-Based Control with Uncertain Motion Model"
      Inventors: Berntorp, Karl
      Patent No.: 11,474,486
      Issue Date: Oct 18, 2022
    • Title: "System and Method for GNSS Ambiguity Resolution"
      Inventors: Berntorp, Karl; Greiff, Marcus
      Patent No.: 11,474,263
      Issue Date: Oct 18, 2022
    • Title: "System and Method for Integer-Less GNSS Positioning"
      Inventors: Berntorp, Karl; Greiff, Marcus
      Patent No.: 11,340,356
      Issue Date: May 24, 2022
    • Title: "Adaptive Control of Autonomous or Semi-Autonomous Vehicle"
      Inventors: Berntorp, Karl; Di Cairano, Stefano; Menner, Marcel
      Patent No.: 11,327,492
      Issue Date: May 10, 2022
    • Title: "Friction Adaptive Vehicle Control"
      Inventors: Berntorp, Karl; Quirynen, Rien; Di Cairano, Stefano
      Patent No.: 11,254,315
      Issue Date: Feb 22, 2022
    • Title: "System and Method for Determining Friction Curve of Tire"
      Inventors: Berntorp, Karl
      Patent No.: 11,203,354
      Issue Date: Dec 21, 2021
    • Title: "System and Method for Controlling Motion of Vehicle with Variable Speed"
      Inventors: Berntorp, Karl; Danielson, Claus; Weiss, Avishai; Di Cairano, Stefano
      Patent No.: 11,091,158
      Issue Date: Aug 17, 2021
    • Title: "System and Method for Controlling Lateral Motion of Vehicle"
      Inventors: Berntorp, Karl; Weiss, Avishai; Danielson, Claus; Di Cairano, Stefano
      Patent No.: 10,994,729
      Issue Date: May 4, 2021
    • Title: "System and Method for GNSS Ambiguity Resolution"
      Inventors: Berntorp, Karl; Weiss, Avishai; Di Cairano, Stefano
      Patent No.: 10,976,444
      Issue Date: Apr 13, 2021
    • Title: "Systems and Methods for Safe Decision Making of Autonomous Vehicles"
      Inventors: Berntorp, Karl; Di Cairano, Stefano; Ahn, Heejin
      Patent No.: 10,860,023
      Issue Date: Dec 8, 2020
    • Title: "Systems and Methods for Intention-Based Steering of Vehicle"
      Inventors: Kalabic, Uros; Berntorp, Karl; Di Cairano, Stefano
      Patent No.: 10,589,784
      Issue Date: Mar 17, 2020
    • Title: "System and Method for Controlling a Vehicle Under Sensor Uncertainty"
      Inventors: Berntorp, Karl; Di Cairano, Stefano
      Patent No.: 10,408,638
      Issue Date: Sep 10, 2019
    • Title: "System and Method for Determining State of Stiffness of Tires of Vehicle"
      Inventors: Berntorp, Karl; Di Cairano, Stefano
      Patent No.: 10,370,004
      Issue Date: Aug 6, 2019
    • Title: "System and Method for Controlling Motion of Vehicle in Shared Environment"
      Inventors: Berntorp, Karl; Okamoto, Kazuhide; Di Cairano, Stefano
      Patent No.: 10,324,469
      Issue Date: Jun 18, 2019
    • Title: "System and Method for Calibrating Parameters of Tires"
      Inventors: Berntorp, Karl; Di Cairano, Stefano
      Patent No.: 10,093,321
      Issue Date: Oct 9, 2018
    • Title: "Methods and Systems for Path Planning Using a Network of Safe-Sets"
      Inventors: Danielson, Claus; Weiss, Avishai; Berntorp, Karl; Di Cairano, Stefano
      Patent No.: 10,012,988
      Issue Date: Jul 3, 2018
    • Title: "SYSTEM AND METHOD FOR CONTROLLING AUTONOMOUS VEHICLES"
      Inventors: Berntorp, Karl; Arslan, Oktay
      Patent No.: 10,012,984
      Issue Date: Jul 3, 2018
    • Title: "System and Method for Determining State of Stiffness of Tires of Vehicle"
      Inventors: Berntorp, Karl; Di Cairano, Stefano
      Patent No.: 10,011,284
      Issue Date: Jul 3, 2018
    • Title: "System and Method for Controlling Vehicle using Neural Network"
      Inventors: Berntorp, Karl; Liu, Ming-Yu; Weiss, Avishai
      Patent No.: 9,989,964
      Issue Date: Jun 5, 2018
    • Title: "System and Method for Controlling Motion of Vehicle"
      Inventors: Di Cairano, Stefano; Kalabic, Uros; Berntorp, Karl
      Patent No.: 9,915,948
      Issue Date: Mar 13, 2018
    • Title: "System and Method for Controlling Autonomous or Semi-Autonomous Vehicle"
      Inventors: Berntorp, Karl; Di Cairano, Stefano
      Patent No.: 9,568,915
      Issue Date: Feb 14, 2017
    See All Patents for MERL