摘要:
Various types and levels of operator assistance are performed within a unified, configurable framework. A model of the device with a model of the environment and the current state of the device and the environment are used to iteratively generate a sequence of optimal device control inputs that, when applied to a model of the device, generate an optimal device trajectory through a constraint-bounded corridor or region within the state space. This optimal trajectory and the sequence of device control inputs that generates it is used to generate a threat assessment metric. An appropriate type and level of operator assistance is generated based on this threat assessment. Operator assistance modes include warnings, decision support, operator feedback, vehicle stability control, and autonomous or semi-autonomous hazard avoidance. The responses generated by each assistance mode are mutually consistent because they are generated using the same optimal trajectory.
摘要:
A method predicts and quantifies the threat posed to a human-operated device based on an optimal device trajectory through a constraint-bounded corridor. A model of the device together with a model of anticipated hazards and the current state of both the device and the hazards are used to iteratively generate an optimal device trajectory through a constraint-bounded corridor or region within state space. Device dynamics are forward-simulated over a time horizon. A method generates a threat assessment metric from the resulting sequence of optimal vehicle states. This threat assessment may be used to devise various types and levels of operator assistance. The human operator can control the device within a safe corridor or region. Threat assessment is based on the nearness of successive optimal trajectory predictions to limits of safe device handling rather than on deviation from a predefined path.
摘要:
A longwall mining machine comprises a rotatable cutting head having a configuration in the form of an equilateral triangle viewed along its axis of rotation and formed with a continuous auger along the outer surface of the head. Cutter bits are located on apexes of the auger. The cutting head is mounted on a boom adjacent the longwall and is geared to produce an eccentric Cardan motion to the head causing the cutter bits to follow a substantially square trajectory in a plane normal to the axis of rotation of the head. Production of coal dust is minimized by deep linear vertical and horizontal cuts extending downwardly from roof to floor. During rotation of the head, cut coal is augered outwardly from the longwall and dropped into a conveyor for removal to a collection area.
摘要:
A method predicts and quantifies the threat posed to a human-operated device based on an optimal device trajectory through a constraint-bounded corridor. A model of the device together with a model of anticipated hazards and the current state of both the device and the hazards are used to iteratively generate an optimal device trajectory through a constraint-bounded corridor or region within state space. Device dynamics are forward-simulated over a time horizon. A method generates a threat assessment metric from the resulting sequence of optimal vehicle states. This threat assessment may be used to devise various types and levels of operator assistance. The human operator can control the device within a safe corridor or region. Threat assessment is based on the nearness of successive optimal trajectory predictions to limits of safe device handling rather than on deviation from a predefined path.
摘要:
Various types and levels of operator assistance are performed within a unified, configurable framework. A model of the device with a model of the environment and the current state of the device and the environment are used to iteratively generate a sequence of optimal device control inputs that, when applied to a model of the device, generate an optimal device trajectory through a constraint-bounded corridor or region within the state space. This optimal trajectory and the sequence of device control inputs that generates it is used to generate a threat assessment metric. An appropriate type and level of operator assistance is generated based on this threat assessment. Operator assistance modes include warnings, decision support, operator feedback, vehicle stability control, and autonomous or semi-autonomous hazard avoidance. The responses generated by each assistance mode are mutually consistent because they are generated using the same optimal trajectory.
摘要:
An active safety framework performs trajectory planning, threat assessment, and semi-autonomous control of passenger vehicles in a unified, optimal fashion. The vehicle navigation task is formulated as a constrained optimal control problem. A predictive, model-based controller iteratively plans an optimal or best-case vehicle trajectory through the constrained corridor. This best-case scenario is used to establish the minimum threat posed to the vehicle given its current state, current and past driver inputs/performance, and environmental conditions. Based on this threat assessment, the level of controller intervention required to prevent collisions or instability is calculated and driver/controller inputs are scaled accordingly. This approach minimizes controller intervention while ensuring that the vehicle does not depart from a traversable corridor. It also provides a unified architecture into which various vehicle models, actuation modes, trajectory-planning objectives, driver preferences, and levels of autonomy can be seamlessly integrated without changing the underlying controller structure.
摘要:
An apparatus (10) for placing a hard compact material such as rock surrounding a drill hole into axial tension for the purpose of breaking and excavating the material by virtue of a dual piston (23) and (25) arrangement disposed within a fluid cylinder (16) wherein the first piston (23) is attached to a thrust rod member (28) the second piston is attached to a wedge member (30) having an outwardly tapered conical end (34) and a feather member (40) surrounding the wedge (30) and thrust (28) members; wherein the feather segments (43) have a conical profile on both their internal and external peripheries.