Mitsubishi Electric Research Laboratories, Inc.

Ford Global Technolgoies, LLC

Uros Kalabic

Stefano Di Cairano

Avishai Weiss

Abraham Goldsmith

Piyush Grover

Daniel Aguilar Marsillach

Tsz-Chun Michael Chiu

Joseph Norman Ulrey

Adam Nathan Banker

Ilya V Kolmanovsky

Julia Helen Buckland

Karl Berntorp

Tobias John Pallett

Rien Quirynen

Matthew John Gerhart

Ankush Chakrabarty

Suzanne Kay Wait

Zhaojian Li

Nils Gustav Nilsson

Tianshu Chu

Vivek Muralidharan

Purnanand Elango

Udit Halder

A computer-implemented method for maintaining a spacecraft near an orbit comprises steps of detecting that a distance from the spacecraft to the orbit is greater than a spacecraft threshold and in response, linearizing dynamics of the spacecraft from a current time over a time horizon with respect to a high-fidelity reference trajectory to produce a state transition matrix (STM) for an uncontrolled motion of the spacecraft within the time horizon. The STM includes non-expanding eigenvectors with magnitudes less than or equal to one and expanding eigenvectors with magnitudes greater than one. The method further comprises determining a control action that changes an upcoming state of the spacecraft to a linear combination of the non-expanding eigenvectors of the STM and generating a control command to an actuator of the spacecraft.

Eigenmotion control for near rectilinear halo orbits

A system for controlling an operation of a vehicle to rendezvous with a target over a finite time horizon, wherein the vehicle and the target form a multi-object celestial system. A processor to formulate passive unsafe regions as passive safety constraints. The passive unsafe regions represents regions of space around the target guaranteeing collision trajectories with the target, in an event of total thruster failure. Update a controller having a model of dynamics of the vehicle with received data, and subject the updated controller to the passive safety constraints to generate control commands that produce a collision free rendezvous trajectory which avoids unsafe regions for the specified time period, guaranteeing a collision free trajectory with respect to the target in the event of the total vehicle thruster failure, so the vehicle does not collide with the target. Output the control commands to activate or not activate thrusters of the vehicle.

Fail-safe vehicle rendezvous in case of total control failure

A method and a system for fault detection and removal in a distributed computing system, implemented as a permissioned blockchain network, is disclosed. The method fault detection comprising compiling and executing a smart contract common for all nodes of the permissioned blockchain network. The smart contract is configured to perform at least one operation from a series of operations comprising: (1) appending transactions including logs indicative of exchanging of messages between the nodes of permissioned blockchain network, (2) detecting malicious behavior of a node in reaching a consensus, and (3) revoking the access of the node upon detecting the malicious behavior. Further, once malicious behavior (and corresponding malicious node) is detected, a consensus is reached between the networked computers of the permissioned blockchain network, by executing a distributed computing program.

Blockchain-based accountable distributed computing system

A satellite for implementing a protocol associated with a distributed satellite position verification system is provided. The satellite, on implementing the protocol, verifies records of positions of one or more other satellites in the distributed satellite position verification system. According to the protocol, the satellite performs, at different time instances, a first operation, a second operation, or a third operation to act as a first satellite, a second satellite, or a third satellite, respectively in the distributed satellite position verification system. When the first satellites performs the first operation, the first satellite verifies at least some positions in the records of positions of the second satellite such that the first satellite: determines a verified position of the second satellite; calculates a deviation between the verified position and a prior estimated position of the second satellite; and records the verified position into the records, based on the calculated deviation.

System for distributed verification of satellite position

Systems and methods controlling an operation of a vehicle in real time to rendezvous the vehicle with a target over a finite time horizon having multiple specified time periods. Select a set of unsafe regions from stored unsafe regions, the set of unsafe regions represents regions of space around the target in which any operation of the PSNO thrusters does not avoid collision with the target, guaranteeing collision trajectories with the target. Formulating the set of unsafe regions as safety constraints, and updating a controller having a model of dynamics of the vehicle with the accepted data. Generating control commands by subjecting the updated controller to the safety constraints to produce a rendezvous trajectory that avoids the set of unsafe regions, guaranteeing an operation of at least the PSNO thrusters, in the event of partial vehicle thruster failure results in a trajectory that does not collide with the target.

Abort-safe vehicle rendezvous in case of partial control failure

A system for optimizing a low-thrust trajectory of a spacecraft trajectory for orbital transfer includes an interface to receive data, a memory to store scheduled geostationary transfer orbit (GTO) data and scheduled geostationary Earth orbit (GEO) data and computer-executable programs, and a processor. The processor is configured to provide a two-dimensional (2D) averaged trajectory consisting of a predetermined revolutions by executing the optimal control program using the GTO data and GEO data, arrange N equidistant points on the 2D averaged trajectory to form segments on the 2D averaged trajectory, obtain osculating elements corresponding to the segments by solving optimization problems for the segments, estimate initial guesses of the segments under continuous thrusting conditions in tangential directions at the N equidistant points, solve a minimum energy optimization problem to obtain a minimum energy 2D osculating trajectory by using as initial guess the concatenation of segments, compute a minimum energy three-dimensional (3D) osculating trajectory by linearly decreasing an inclination of the minimum energy 2D osculating trajectory to zero, and generating a minimum fuel 3D osculating trajectory by iteratively solving a cost function while changing a parameter from one to zero.

System and method for optimizing a low-thrust trajectory of a spacecraft trajectory

A method and system for activating thrusters of a vehicle for trajectory-tracking control of the vehicle. A transfer orbit generator to generate a transfer orbit for the vehicle from an initial orbit to a target orbit, and a feedback stabilization controller. Compute the target orbit for the vehicle about the celestial body. Compute a free trajectory with patch points along the free trajectory using a free trajectory module, each patch point includes a position and a velocity. Determine a feedback gain at each patch point using a feedback gain module, wherein a state penalty function at each patch point is set to match a state uncertainty function at the same patch point. Apply the feedback gain at each patch point to map the position and the velocity at each patch point to delta v commands, to maintain the target orbit using a feedback stabilization controller.

Tracking neighboring quasi-satellite orbits around Mars's moon Phobos

A system for controlling an operation of a machine subject to state constraints in continuous state space of the machine and subject to control input constraints in continuous control input space of the machine is provided. The apparatus includes an input interface to accept data indicative of a state of the machine, a memory configured to store an optimization problem for computing the safety margin of a state and action pair satisfying the state constraints and a control policy mapping the state of the machine within a control invariant set (CIS) to a control input satisfying the control input constraints, and a processor configured to iteratively perform a reinforcement learning (RL) algorithm to jointly control the machine and update the control policy.

Constraint adaptor for reinforcement learning control

A system for controlling an autonomous vehicle includes a memory configured to store parameters of a g-g plot defining admissible space of values of longitudinal and lateral accelerations. The g-g plot parameters define a mapping between user driving preferences and constrained control of the autonomous vehicle. The g-g plot parameters include a maximum forward acceleration, a maximum backward acceleration, a maximum lateral acceleration and a shape parameter defining profile of curves connecting maximum values of forward, backward, and lateral accelerations. The system accepts a comfort level as a feedback from a passenger of the vehicle, determines a dominant parameter corresponding to the feedback, updates the dominant parameter of the g-g plot based on the comfort level indicated in the feedback, and controls the vehicle to maintain dynamics of the vehicle within the admissible space defined by the parameters of the updated g-g plot.

Control of autonomous vehicles adaptive to user driving preferences

A system for direct and indirect control of mixed-autonomy vehicles receives a traffic state of a group of mixed-autonomy vehicles traveling in the same direction, wherein the group of mixed-autonomy vehicles includes controlled vehicles willing to participate in a platoon formation and at least one uncontrolled vehicle, and wherein the traffic state is indicative of a state of each vehicle in the group, submit the traffic state into a parameterized function trained to transform the traffic state into target headways for the mixed-autonomy vehicles to produce the target headways, and submit the target headways to a headway-based model configured to map the target headways to target speeds of the mixed-autonomy vehicles to produce the target speeds. The system determines and transmits control commands to the controlled vehicle based on one or combination of the target headways and the target speeds.

Direct and indirect control of mixed-automata vehicle platoon

Methods and systems including processor configured to receive a transition indication to switch a semi-autonomous vehicle from a driving mode to another driving mode while a driver is driving the vehicle on a roadway. Wherein the driving modes include an autonomous lane keeping mode, an autonomous lane change mode and a manual mode. In response to receiving the request, use protocol data to assess a status of the vehicle's environment, a vehicle state and systems of the vehicle. Select, a set of conditions corresponding to the vehicle's state, based on one or more of the assessments. Determine, whether a switch between driving modes is initiated by the driver, by verifying if the vehicle's state satisfies the set of conditions, in order to validate if the driver actuated the vehicle into or out of a safety region.

Method and system for determining driver intention in semi-autonomous vehicle steering

A traffic control system for controlling a traffic of cooperative and uncooperative vehicles determines delays on each segment of the roads of the network based on the current state of the flow of the traffic and determines flows of the cooperative and uncooperative vehicles that satisfy a Nash equilibrium for the cooperative vehicles having a common objective and the uncooperative vehicles having individual objectives. The system determines, for the cooperative vehicles, costs of segments of the roads that correspond to the Nash equilibrium and determines routes for the cooperative vehicles based on the current locations and target locations of the cooperative vehicles, and the costs of the segments of the roads in the network determined for the cooperative vehicles. The routes are transmitted to corresponding cooperative vehicles.

System and method for asymmetric traffic control

A control system for controlling an operation of a processing machine positioning a worktool according to a processing pattern to machine a workpiece. A memory to store a reference trajectory defined in a spatial domain by a sequence of points for positioning the worktool and defined in a time domain by a relative time for positioning the worktool on each point of the reference trajectory. A sensor to determine a state of the processing machine. A reference governor to iteratively process the reference trajectory over a receding horizon including multiple windows of points, and analytically update the relative time for positioning the worktool for some points of the reference trajectory within the receding horizon to satisfy constraints on the operation of the processing machine having the state. A controller to control the operation of the processing machine using control inputs causing the worktool to track the updated reference trajectory.

Receding horizon reference governor

Systems and methods for a control system for controlling a machine including a first controller to generate a first control command according to an objective of control. A second controller to generate a control input as a combination of a second control command and a third control command. Wherein the second controller generates the second control command according to the objective of control, and generates the third control command using a product of a gain with a difference between the first control command and the second control command. A motor to control the machine according to the control input.

Methods and systems for balanced feasible and stable control

Systems and methods for an imaging system having a memory with a historical localization dictionary database having geo-located driving image sequences, such that each reference image is applied to a threshold to produce a binary representation. A sensor to acquire a sequence of input images of a dynamic scene. An encoder to determine, for each input image in the sequence, a histogram of each input image indicating a number of vertical edges at each bin of the input image and to threshold the histogram to produce a binary representation of the input image. A visual odometer to compare the binary representations of each input image and each reference image, by matching an input image against a reference image. Wherein the visual odometer determines a location of the input image based on a match between the input image and the reference image.

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Uros Kalabic