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dc.contributor.advisorKarl Iagnemma.en_US
dc.contributor.authorConstantin, Alexandre, S.M. Massachusetts Institute of Technologyen_US
dc.contributor.otherMassachusetts Institute of Technology. Department of Mechanical Engineering.en_US
dc.date.accessioned2014-12-08T18:52:08Z
dc.date.available2014-12-08T18:52:08Z
dc.date.copyright2014en_US
dc.date.issued2014en_US
dc.identifier.urihttp://hdl.handle.net/1721.1/92146
dc.descriptionThesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.en_US
dc.descriptionCataloged from PDF version of thesis.en_US
dc.descriptionIncludes bibliographical references (pages 139-145).en_US
dc.description.abstractThis thesis describes the design of an unified framework for threat assessment and the shared control between a human driver and the onboard controller, based on the notion of fields of safe travel. It allows to perform corridor navigation, trajectory planning, threat assessment and driving assistance in hazardous situations. A new approach to the threat assessment problem is introduced, based upon the estimation of the control freedom afforded to a vehicle. Given sensor information of the surrounding environment, an algorithm first identifies corridors of travel through which the vehicle can safely navigate. The second stage then consists in assessing the potential threat posed to the vehicle in each identified corridor thanks to a metric associated with available control margin. For this purpose, the fields of safe travel are associated with sets of homotopic trajectories generated either from a lattice sampled in the vehicles input space or from a conformal state lattice. This level of threat is the keystone of the system and serves as input to influence autonomous navigation or driver support inputs. The semi-autonomous control system aims to honor safe driver inputs while ensuring safe and robust navigation properties. It ideally operates only during instances of significant threat: it should give a driver full control of the vehicle in "low threat" situations but apply appropriate levels of computer-controlled actuator effort during "high threat" situations. This approach preserves the freedom of control of the human driver when he/she remains within a safe navigable corridor, and adjust the vehicle trajectory when its predicted future state falls out of a safe field, or when the lowest threat exceeds some threshold. In fully autonomous mode, this human-inspired motion planning approach ensures collision free navigation and driving comfort.en_US
dc.description.statementofresponsibilityby Alexandre Constantin.en_US
dc.format.extent145 pagesen_US
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsM.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582en_US
dc.subjectMechanical Engineering.en_US
dc.titleA margin-based approach to vehicle threat assessment in a homotopy framework for semi-autonomous highway navigationen_US
dc.typeThesisen_US
dc.description.degreeS.M.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Mechanical Engineering
dc.identifier.oclc896822425en_US


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