103 results about "Steering ratio" patented technology

A steering ratio control system of a vehicle includes a variable steering ratio mechanism variably adjusting a steering ratio of a steer angle at left and right steered road wheels to a steering-wheel rotation angle, and a braking / driving force control unit individually controlling braking force and / or driving force of the left and right steered wheels. A steering ratio control unit determines a reference steering ratio based on a vehicle's driving state. The steering ratio control unit calculates a steering-ratio correction value needed for canceling torque steer resulting from a difference in braking force and / or driving force between the left and right steered wheels. A final steering ratio is determined based on both of the reference steering ratio and the steering-ratio correction value to drive the variable steering ratio mechanism responsively to the final steering ratio reflecting the steering-ratio correction value.

A steering ratio control system of a vehicle includes a variable steering ratio mechanism variably adjusting a steering ratio of a steer angle at left and right steered road wheels to a steering-wheel rotation angle, and a braking / driving force control unit individually controlling braking force and / or driving force of the left and right steered wheels. A steering ratio control unit determines a reference steering ratio based on a vehicle's driving state. The steering ratio control unit calculates a steering-ratio correction value needed for canceling torque steer resulting from a difference in braking force and / or driving force between the left and right steered wheels. A final steering ratio is determined based on both of the reference steering ratio and the steering-ratio correction value to drive the variable steering ratio mechanism responsively to the final steering ratio reflecting the steering-ratio correction value.

A steering control apparatus for a vehicle including a steering input unit movable to set a steering input, and a steering output unit arranged to output a steering output, the steering input unit being connected via a cable to a body of the vehicle, includes a steering ratio control unit, a steering limiter, and a cable-attachment diagnostic controller. The steering ratio control unit regulates a variable steering ratio as a rate of change in the steering output with respect to a change in the steering input. The steering limiter restricts movement of the steering input unit to limit the steering input. The cable-attachment diagnostic controller is activated in a cable-attachment diagnostic mode, to control the steering ratio in such a manner that the steering input unit is movable over an allowable region defined by the steering limiter when the cable is correctly attached.

An object of the present invention is to reduce the possibility of a power assistance failure because of the phenomenon that steering assisting power which an electric power steering unit can generate is lower than the steering assisting power which is required for the electric power steering unit. A vehicle steering control device comprises an electric power steering unit, a steering ratio varying unit which drives an output member relative to an input member driven by steering operation of a driver to vary a steering ratio, and a control means which controls the steering ratio varying unit. The control means decreases in magnitude the relative drive velocity of the output member driven by the steering ratio varying unit relative to the input member when the magnitude of a difference between the maximum value of the steering drive velocity range of said steerable wheels which allows said power steering unit to generate a required steering assisting power and an actual steering drive velocity of said steerable wheels is small in contrast to the large difference.

The invention belongs to self-steering systems for automatic navigation of agricultural machines and particularly relates to a self-steering proportional control valve block and a navigation hydraulic system based on the self-steering proportional control valve block. The valve block is provided with a first pressure oil feed inlet, a second pressure oil feed inlet, an oil return port, a first steering hydraulic cylinder connector, a second steering hydraulic cylinder connector, a first load pressure feedback port and a second load pressure feedback port and comprises a load sensing oil port and a three-position and five-way proportional directional valve, a fixed-differential reducing valve, a one-way valve and a differential pressure type overflow valve, wherein the median function of the three-position and five-way proportional directional valve is in the Y type. An automatic navigation system can be formed by connecting the valve block with a core-opening full-hydraulic steering gear or a core-closing full-hydraulic steering gear or a load sensing type core-closing full-hydraulic steering gear. When the navigation system works, the quantity of oil flowing into the steering hydraulic cylinder is only related to the opening degree of the three-position and five-way proportional directional valve and is basically not affected by the change of the load of the steering hydraulic cylinder. According to the self-steering proportional control valve block, heat loss is small, the control accuracy is high, and the response speed is high.

A steering control apparatus for a vehicle including a steering input unit movable to set a steering input, and a steering output unit arranged to output a steering output, the steering input unit being connected via a cable to a body of the vehicle, includes a steering ratio control unit, a steering limiter, and a cable-attachment diagnostic controller. The steering ratio control unit regulates a variable steering ratio as a rate of change in the steering output with respect to a change in the steering input. The steering limiter restricts movement of the steering input unit to limit the steering input. The cable-attachment diagnostic controller is activated in a cable-attachment diagnostic mode, to control the steering ratio in such a manner that the steering input unit is movable over an allowable region defined by the steering limiter when the cable is correctly attached.

A method for calculating the steering ratio at road cross based on genetic algorithm and maximum entropy model includes inputting flow rate data in certain time slot at study road cross and adjacent road cross, setting operator and control parameter of said algorithm and defining its search space and total frequency of solving solution, initializing calculation environment of said algorithm, executing genetic algorithm, calculating entropy of obtained solution and judging whether said total frequency is up or not if precision of obtained solution is satisfied and using solution corresponding maximum entropy as final solution if it is.

A steering system (10) and a method of dampening the forces transmitted to a steering wheel (20) of a vehicle when a steerable wheel (22) of the vehicle collides with an obstacle using the steering system (10). The method includes steering a vehicle via a steering wheel (20) operably connected to a steerable wheel (22), with the steering wheel (20) defining an input angle. The method also includes monitoring the rate of change of a steering angle (40) as defined by the steerable wheel (22), with the ratio of the input angle to the steering angle (40) defining a steering ratio. The method further includes reducing an amount of torque transmitted to the steering wheel (20) from the steerable wheel (22) when the rate of change of the steering angle (40) exceeds a maximum rate by adjusting the steering ratio (40).

The invention discloses a road deviation monitoring method. The method comprises the following steps: acquiring the driving state data of an automobile through a positioning module; comparing the driving state data with road data in a high-precision electronic map, and determining a road point optimally matched with a current position point in the driving road of the automobile; acquiring steering wheel angle data; determining the predication locus of the automobile through combining the internal and external steering ratio factor and the front and rear wheel base of the automobile according to the steering wheel angle data; predicating the predication position point of the automobile in the predication locus after driving a preset distance; determining a predication road point optimally matched with the predication position point in the road of the high-precision electronic map; and determining whether the automobile deviates from the road or not according to exceeding of a difference between a first deviation and a second deviation of a preset threshold or not. Compared with traditional technologies, the road deviation detection method adopting the above technical scheme is no longer dependent on an image visual technology in order to avoid light and other environment fluencies and improve the accuracy of detection and early warning.

A dolly for the transport of elongated loads which includes an adjustable steer linkage assembly, an adjustable steer ratio, means for switching between rear- and forward-steering, and manual over-ride of the self-steering configuration. All of these adjustments can be achieved without the need to manually delink subassemblies.

In a variable ratio steering system of a vehicle with a variable steering ratio mechanism varying a steering ratio R of steering wheel angle θS to road wheel steer angle θW at steered road wheels, a vehicle speed sensor, and a steering angle sensor, a steering ratio control unit controls the steering ratio according to a fixed steering ratio characteristic when the steering wheel angle θS is less than or equal to a predetermined angle θ1 substantially corresponding to a neutral position of a steering wheel. Conversely when the steering wheel angle θS is greater than the predetermined angle θ1 substantially corresponding to the neutral position of the steering wheel, the steering ratio control unit controls the steering ratio according to a vehicle-speed dependent steering ratio characteristic that a steering angle versus road wheel steer angle characteristic varies depending on a vehicle speed value.

A first reduction ratio established between first internal teeth of an input gear and first external teeth of a first planetary gear of an annular planetary gear unit is set different from a second reduction ratio established between a second internal teeth of an output gear and second external teeth of a second planetary gear of the annular planetary gear unit. A rotation cam unit is installed in a circular opening of the annular planetary gear unit to cause, upon rotation thereof, the first and second planetary gears to make an eccentric rotation relative to a common axis of the first and second internal teeth thereby to induce a circumferential movement of a first meshed portion between the first external teeth and the first internal teeth and a second meshed portion between the second external teeth and the second internal teeth. The rotation cam unit is actuated by an electric motor.

The invention relates to a position control method for a sensorless steering wheel. According to the position control method, continuous, smooth and stepless change of a steering ratio at different car speeds is realized by a regulation motor for controlling an ECU (Electronic Control Unit) gear ratio; meanwhile, the change rule is calculated by utilizing a correlation formula, and rotation angle compensation is carried out according to the calculated change rule; reverse steering adjustment is actively carried out during car oversteer, and the regulation motor and an assisting motor are flexibly controlled and mutually compensated so as to perfectly combine the flexibility, the portability and the control stability of the steering, so that the control performance and the safety are improved.

A vehicle for line marking, having a steering mechanism (10) including: a directional wheel (5) that pivots about a steering shaft (12) coupled to a steering actuator (13); a control actuator (21) responsive to a steering wheel (22); and a universal joint coupling the control actuator (21) and the steering actuator (13) at a fixed angle between 20° to 70°, preferably 30° to 60°; the angle of the universal joint acting to produce a varying steering ratio as the steering wheel is moved away from its centred position. The vehicle includes a hydraulic pump circuit for a motor (101) driven line marking spray device (77) having a hydraulic supply line (105) for the motor with a check valve (107) and a high pressure accumulator (109) between the check valve and the motor and a pressure actuated ram (102) to deactivate the pump (100) when the pressure exceeds a threshold; the motor return line having a low pressure accumulator (110) and a restricted (112) bypass line (111).

A personal watercraft can have a steering nozzle pivoting in accordance with the operation of a steering handle unit to change the traveling direction of a vehicle body. A steering position sensor can be configured to detect the steering angle of the steering handle unit. An actuator can be arranged to pivot the steering nozzle to change the steered angle thereof. A running speed sensor can be configured to detect the running speed of the vehicle body, and a control device. The control device can determine an operational amount of the actuator and control the actuator based upon the detection amount of the steering position sensor, the running speed sensor, and a steering ratio preset with reference to the steering angle and the running speed. The steering ratio is set to be smaller as the running speed becomes larger.

A steering arrangement including a first, second, third and fourth hydraulic chamber, the first and third chambers being operable to steer in a first direction and the second and fourth chambers being operable to steer in a second direction. A pump system supplies fluid to a steering system, which is operable to supply the pressurised fluid to one or more of the first, second, third and fourth hydraulic chambers. The steering system having a first mode wherein fluid is supplied to the first and third hydraulic chambers to steer in the first direction, or pressurised fluid is supplied to the second and fourth hydraulic chambers to steer in the second direction. The steering system having a second mode to steer in the first direction, or to steer in the second direction, such that the steering ratio is higher in the second mode than in the first mode.

The invention aims to reduce the possibility of a power assistance failure because of the phenomenon that steering assisting power producible by an electric power steering device is lower than the steering assisting power required for the electric power steering device. A power steering control device comprises an electric power steering device, a steering ratio varying device for varying the steering ratio by driving an output member relatively to an input member driven by the steering operation by the driver, and a control device for controlling the steering ratio varying device. When the difference between the maximum value of the steering drive speed range of the steering wheel for which a required steering assisting power producible by the power steering device and an actual steeringdrive speed of the steering wheel is small, the control device decreases the relative drive speed of the output member with respect to the input member by the steering ratio varying device in contrast to the large difference.

A steering apparatus for an automotive vehicle is provided with an electric drive unit that varies a steering ratio between a road wheel angle and a steering wheel angle of the vehicle, a temperature sensor that detects a temperature of the electric drive unit, and a control unit including a steering ratio characteristic setting block that sets a characteristic of the steering ratio including a steering gain and a steering response rate in accordance with an operating state of the vehicle and, when the temperature of the electric drive unit exceeds a first temperature threshold, adjusts the steering response rate in such a manner that the steering response rate comes closer to a base steering response rate level as the temperature of the electric drive unit becomes increased and a drive block that drives the electric drive unit to vary the steering ratio according to the steering ratio characteristic.

A vehicle steering control device includes an electric power steering unit, a steering ratio varying unit which drives an output member relative to an input member driven by steering operation of a driver to vary a steering ratio, and a control unit which controls the steering ratio varying unit. The control unit decreases in magnitude the relative drive velocity of the output member driven by the steering ratio varying unit relative to the input member when the magnitude of a difference between the maximum value of the steering drive velocity range of said steerable wheels which allows said power steering unit to generate a required steering assisting power and an actual steering drive velocity of said steerable wheels is small in contrast to the large difference.

A steering arrangement (20) including a first hydraulic pressure chamber (31), a second hydraulic pressure chamber (32), a third hydraulic pressure chamber (33) and a fourth hydraulic pressure chamber (34), the first and third pressure chambers (31, 33) being selectively operable to steer in a first direction and the second and fourth pressure chambers (32, 34) being selectively operable to steer in a second direction, a pump system (22) for supplying pressurised fluid to a steering system (24), the steering system (24) being operable to supply the pressurised fluid to one or more of the first, second, third and fourth hydraulic pressure chambers (31, 32, 33, 34), the steering system (24) having a first mode wherein pressurised fluid is simultaneously supplied to the first and third hydraulic pressure chambers (31, 33) to steer in the first direction or wherein pressurised fluid is simultaneously supplied to the second and fourth hydraulic pressure chambers (32, 34) to steer in the second direction, the steering system having a second mode wherein pressurised fluid is supplied to one of the first and third hydraulic pressure chambers (31, 33) to steer in the first direction or wherein pressurised fluid is supplied to one of the second and fourth hydraulic pressure chambers (32, 34) to steer in the second direction, such that the steering ratio is higher in the second mode than in the first mode.

A steering system (10) and a method of dampening the forces transmitted to a steering wheel (20) of a vehicle when a steerable wheel (22) of the vehicle collides with an obstacle using the steering system (10). The method includes steering a vehicle via a steering wheel (20) operably connected to a steerable wheel (22), with the steering wheel (20) defining an input angle. The method also includes monitoring the rate of change of a steering angle (40) as defined by the steerable wheel (22), with the ratio of the input angle to the steering angle (40) defining a steering ratio. The method further includes reducing an amount of torque transmitted to the steering wheel (20) from the steerable wheel (22) when the rate of change of the steering angle (40) exceeds a maximum rate by adjusting the steering ratio (40).

The embodiment of the invention provides a traffic situation simulation method, a system and electronic equipment. The method comprises the following steps: determining a road network area which is used as a simulation target and comprises one or more sub-area road networks; obtaining the edge road section flow of each sub-region road network and the entrance steering proportion of an intersectionentrance in each sub-region road network in a simulation target time period; according to the flow of the edge road section and the entrance steering proportion, estimating to obtain a simulated driving track of a vehicle driving into the subarea road network; establishing a corresponding traffic situation simulation environment for each sub-region road network; and loading simulation data containing the simulated driving track in the traffic situation simulation environment to realize traffic situation simulation. Compared with the scheme in the prior art, the method provided by the embodiment of the invention can improve the simulation accuracy and the simulation precision.

Disclosed is a method for actuating a superimposed steering system, a superimposed steering system, a controller, a computer program, and a computer program product. In the method, a steering ratio is produced as a function of the driving speed, with the magnitude of a time delay being adjusted as a function of the driving speed.

An operation torque estimating portion estimates an operation torque Th of a driver based on an input angle θh and an input torque T output from a torque sensor. A non-holding state detecting portion determines whether the driver is holding a steering wheel by comparing an absolute value of the operation torque Th and a predetermined value ε1. An equilibrium detecting portion determines whether an equilibrium point is reached by comparing the absolute value of the input torque T with a predetermined value ε2. When it is determined that the driver is not holding the steering wheel and the equilibrium point is reached, a switching portion switches to such a position that causes a target steering adjusting portion to multiply a target output angle θ pm by a predetermined gain G according to the input torque T so that the target steering angle is made smaller.

An electronic control unit for a steer-by-wire vehicle steering system includes a data storage component that stores a desired lateral acceleration versus steering angle profile with regard to a range of vehicle speeds and a processor operably and electronically coupled with a steering wheel angle sensor and a yaw sensor. The data storage component includes electronic instructions that causes the processor to receive steering wheel angle data over a range of vehicle speeds, receive vehicle yaw data over the range of vehicle speed correlated to the steering wheel angle data, generate an observed lateral acceleration versus steering angle profile with regard to the range of vehicle speeds, and generate a steering ratio correction based on a comparison of the desired lateral acceleration versus steering angle profile and the observed lateral acceleration versus steering angle profile.

The invention relates to a vehicle steering control method and system. An angle sensor is arranged on a steering wheel and used for detecting the rotating angle of the steering wheel. A control unit calculates the wheel target steering angle according to the signal of the angle sensor. According to the differential value between the wheel target steering angle and the wheel actual steering angle,the control unit outputs corresponding steering proportional direction valve control current, and a steering proportional direction valve controls steering of a vehicle through a steering oil cylinder. The system is convenient to install, steering control is convenient and reliable, and the cost can be reduced effectively.

The invention provides a steering control method and device and an automobile. The steering control method is applied to a vehicle comprising a power-assisted steering device. The steering control method comprises the following steps: acquiring the current vehicle speed and steering wheel rotation data of the vehicle; calculating a theoretical steering ratio and a limited steering ratio corresponding to the current vehicle speed and steering wheel rotation data according to the current vehicle speed and steering wheel rotation data; determining an actual steering ratio according to the theoretical steering ratio and a limited steering ratio; outputting a steering ratio output control instruction to the power-assisted steering device according to the actual steering ratio. According to the embodiment of the invention, under the condition that the conventional power-assisted system is not changed, namely under the condition that driving habits are not changed, the steering angle input by rotating the steering wheel by a driver is adjusted according to the vehicle speed and steering wheel rotation data, so that a small steering angle can be output under the conditions that the steering wheel is swerved at a high speed and the like, and the driving safety is improved.

The invention discloses an intersection traffic state parameter estimation method and system based on multi-source data. The method comprises the following steps: building a vehicle delay model according to a traffic wave theory, and building a vehicle travel time model of a flow direction level according to the speed distribution characteristics of a vehicle; enabling a fixed-point detector to detect and obtain the flow of the road section entrance, and determining the number of vehicles arriving at the road section entrance; determining a traffic flow steering ratio of a road section by setting a virtual travel line according to a vehicle track acquired by a mobile detector; determining Bayesian networks of different flow directions according to the vehicle travel time model, the number of arrival vehicles and the traffic flow steering ratio; and solving the Bayesian network and determining the maximum queuing length and the average travel time of the vehicles in different flow directions. According to the embodiment of the invention, the vehicle track data and the fixed-point detector data are combined, and the parameter estimation method fusing the traffic wave theory and statistical analysis is established, so that the accuracy of traffic state parameter estimation is effectively improved.

According to an active front steering system (AFS) of the invention, an actuator assembly that receives steering input from a driver and AFS input from a motor is mounted to a gear box that reciprocates a rack bar connected to tie rods that are connected to wheels. Therefore, the entire size of the AFS is reduced and a decelerator that changes the steering ratio includes a single planetary gear that outputs final steering through rack bar after the steering input from the driver and the AFS input from motor are inputted across each other.