51results about How to "Improve steering feel" patented technology

An outboard motor steering system for an outboard motor mounted on a stern of a boat and having an internal combustion engine and a propeller with a rudder powered by the engine to propel and steer the boat. The system includes a swivel shaft connected to the propeller, a swivel case rotatably accommodating the swivel shaft, and a hydraulic cylinder connected to the swivel shaft to rotate it. The swivel case is formed with a box-like recess to accommodate the hydraulic cylinder therein such that the hydraulic cylinder does not project outside a profile of the outboard motor, regardless of a steered angle of the outboard motor. A rotation angle sensor is also installed in the recess and outputs a signal indicative of an angle of swivel shaft rotation. Further, moving orifices are provided in a hydraulic pressure circuit of the actuator for relieving excessive hydraulic pressure. Thus, space utilization around the outboard motor and boat is not restricted and steering feel is improved.

The invention relates to an optimum determining method of power steering torque of electric power steering system of vehicle. At first, the torque of the starting power-steered steering wheel can be determined; the torques of the starting power-steered steering wheel in different speed intervals are set: T0(v0) is equal to plus or minus 1Nm; T1 (v1) is equal to plus or minus 1.5Nm; and T2(v2) is equal to plus or minus 2Nm. Secondly, the coefficient of proportionality of the starting steering power of a motor V (Vi) (i is equal to 0,1 and 2) is determined, according to the operation of the vehicle (idle load of vehicle and relevant parameters of vehicle) and the effects of steering power. Thirdly, the maximum power steering torque of the motor is determined; and the torque Tdtest of the rotary steering wheel of the vehicle requiring an EPS system is measured in the state of maximum load and the stationary state. Fourthly, the coefficient (M / m).V(Vi) of the actual steering power is regulated according to the vehicle load, speed and requirements for the steering system. Fifthly, the optimum power steering current of the motor of the EPS system is determined, according to the whole weight M, the running speed V, the torque Td and the parameters of the steering system of the vehicle under the actual running condition.

The invention discloses a joint control method of ESP and EPS when a vehicle turns to avoid collision in an emergency, including: 1. Obtaining the longitudinal vehicle speed v by using a wheel speed sensor x , use the steering wheel angle sensor to obtain the front wheel angle δ parameter; 2 Calculate the expected angular velocity through the two-degree-of-freedom vehicle dynamics model 3 Calculate the maximum yaw rate to ensure vehicle stability through the road surface adhesion limit 4 compare and If there is a wrong operation, the coordinated control will be carried out. If there is no wrong operation, then the EPS and ESP will work normally; 5. When the driver makes a wrong operation, adjust the power assist torque; Correct the power-assist torque provided by the EPS motor to assist the driver's operation and avoid or weaken the side slip of the front axle caused by the driver's excessive steering wheel.

A motor control device includes control calculation means formed by an open loop control unit and a dq-axis / 3-phase conversion unit. The open loop control unit obtains voltage instruction values vd, vq on the d-axis and q-axis according to current instruction values id*, iq* on the d-axis and q-axis, the armature winding interlinking magnetic flux quantity f, and the rotor angular velocity omega e in the motor. The dq-axis / 3-phase conversion unit converts the voltage instruction values vd, vq into phase voltage instruction values Vu, Vv, Vw. On the other hand, a data acquisition unit acquires angle-dependency data indicating dependency on the electric angle indicated by a secondary higher harmonic component concerning the electric angle of the d-axis or the q-axis component of the motor current according to the current detection value ia and the electric angle theta. A correction coefficient decision unit decides a correction coefficient for correcting the phase voltage instruction value so as to reduce the dependency according to the angle-dependency data. A correction execution unit corrects the phase voltage instruction values Vu, Vv, Vw obtained by the dq-axis / 3-phase conversion unit, according to the decided correction coefficient.

[Problem] To provide an electric power steering device capable of reducing a sense of discomfort due to noise when steering or when executing low-speed steering, and capable of achieving smooth steering without phase delay during high-speed steering. [Solution] An electric power steering device includes a torque control unit that computes a current command value on the basis of at least a steering torque, and assist-controls a steering system by driving a motor using a current control system based on the current command value. The electric power steering device is provided with: a motor angular velocity computing unit that computes a motor angular velocity from a motor rotation angle; a motor angular acceleration computing unit that computes a motor angular acceleration from the motor angular velocity; and a stability compensation unit that computes a compensation steering torque and a compensation current command value on the basis of the motor angular velocity and the motor angular acceleration (and additionally the vehicle speed as necessary), wherein the steering torque is compensated using the compensation steering torque and the current command value is compensated using the compensation current command value.

The invention discloses an electronic differential control method of a four-wheel drive electric vehicle. The electronic differential control method includes the steps of calculating the turning radiuses of two front wheels and the turning radiuses of two rear wheels according to the turning angles of wheels and the slip angles of tires correspondingly, calculating target wheel speeds of the fourwheels according to the reference vehicle speed and the obtained turning radiuses of the two front wheels and the two rear wheels correspondingly, monitoring the difference between the actual wheel speeds of the four wheels and the target wheel speed in real time, determining the output modification feedback torque of each wheel by multiplying the difference by a preset torque modification proportionality coefficient, modifying the output torque, and obtaining the actual torque of the driving wheels inside and outside a front axle and a rear axle by subtracting the torque difference from the driving wheels inside, adding the torque difference to the driving wheels outside and meanwhile adding the feedback torque based on target wheel speed modification correspondingly. The electronic differential control method is suitable for the four-wheel independent drive electric vehicle, the turning radius and target torque of each driving wheel are calculated independently, the torque can be rapidly and precisely controlled, the slip angles of the tires are introduced to participate in calculation, and precision is improved.

The electric power steering device 10 is equipped with a determination part 60 to determine a state of going or returning. The determination part 60 to determine the state of going or returning determines the state of the steering wheel as a returning state, and thereafter the returning state is continued until an absolute value of a rotation speed of the motor to be detected by a detection part of the rotation speed of the motor reaches not more than a predetermined value BB.

The present disclosure provides an automobile reducer including a worm shaft bearing coupled to an end of a worm shaft meshing with a worm wheel, the end lying opposite a portion of the worm shaft coupled to a motor shaft; a bush coupled to an outer peripheral surface of the worm shaft bearing, the bush having an incision formed by incising one side of the bush; a damper coupled to an outer peripheral surface of the bush inside a housing so as to force the bush against the worm shaft bearing and to elastically support between the housing and the worm shaft bearing; and a clearance compensation mechanism penetrating the damper and pressurizing the bush towards the worm wheel. The automobile reducer can accurately assist the driver's steering wheel manipulation.

The invention provides an electric power steering system, a control method and a vehicle. The electric power steering system comprises a torque sensor, a friction compensation module and a motor control module, wherein the torque sensor is used for detecting a frictional resisting moment of the vehicle; the friction compensation module obtains an original friction compensation moment, calculates afriction compensation correction coefficient Kf' of the vehicle according to the original friction compensation moment and the frictional resisting moment detected by the torque sensor and calculatesa friction compensation current; and the motor control module compensates the current according to the friction compensation current and performs power steering control. According to the electric power steering system, the frictional resisting moment of the vehicle is measured by using the torque sensor, and the friction compensation current of the vehicle is calculated by using the friction compensation module according to the frictional resisting moment, differentiated friction compensation output is realized, and the steering hand feel is improved.

The invention relates to an automotive chassis system integration multi-objective optimization method based on an improved cell membrane optimization algorithm. The method includes steering and suspension system optimization, wherein the steering system optimization includes selection of transmission ratio of a steering servo motor and adoption of torque sensor rigidity and electric motor rotation inertia serving as design variables, the suspension system optimization includes selection of suspension rigidity and adoption of suspension transverse stabilizer bar angle rigidity, suspension damp and tire cornering stiffness serving as integrated optimization objectives. The steering road feel and steering sensitivity of a novel electric power steering system and the smoothness of an active suspension system serve as integrated optimization objectives, the steering stability, steering sensitivity and suspension dynamic deflection limit serve as integrated constraint conditions, the improved cell membrane optimization algorithm is applied to perform optimization design. Finally, an optimum compromise solution under a desirability function is selected as an optimization result according to a Pareto solution, and accordingly integrated optimization of vehicle running smoothness, operating stability and safety is achieved.

A power steering system provides improved steering feel whenever negligible power assist is required is required such as during on-center operation or at very high vehicular speeds. The power steering system includes fluid lines used for directly coupling a motor driven pump to a power cylinder. The fluid lines are coupled to a system reservoir or to one another whenever a primary control signal indicative of steering wheel torque has a value below a selected threshold value thereby substantially decoupling the power cylinder from the pump.

The invention provides electric power steering apparatus includes an operation amount detecting unit for detecting an operation amount of an operation member for steering a motor vehicle; a reference assist characteristics setting unit for setting reference assist characteristics which are reference characteristics of a motor driving target value corresponding to the operation amount of the operation member; a motor driving target value setting unit for setting a motor driving target value in accordance with corrected assist characteristics obtained by shifting the reference assist characteristics along an axis of coordinates of the operation amount; a yaw rate detecting unit for detecting or estimating a yaw rate of the motor vehicle; and a shifting amount setting unit for setting a shifting amount of the corrected assist characteristics with respect to the reference assist characteristics corresponding to the yaw rate of the motor vehicle.

The invention discloses a multi-objective optimization method based on a cell membrane optimization algorithm and used for an automotive complex steering system. Mechanical parameters and hydraulic parameters having greater influence on steering performance are selected from the complex steering system to serve as optimization variables, steering feel, steering sensitivity and energy consumption are taken as optimization objectives, and the steering assisting range is taken as a constraint condition, so that the system can obtain good steering feel and steering sensitivity with lower energy consumption.

Discloses is a reducer of an electric power steering apparatus. The reducer of the electric power steering apparatus can reduce the rattling noise caused by an increase of backlash due to friction and abrasion of a worm and a worm wheel or by an impact transferred through a wheel and a steering shaft from the road and allowing a pivotal movement of a worm shaft, while decreasing a rotation resistance and blockage of a worm shaft and a worm shaft bearing to increase steering feel of a driver.

A motor controller includes a converter including a plurality of switching elements controlled by PWM to generate sinusoidal waves of multiple phases; a motor including a stator coil and a rotor, the stator coil is provided with a generated a sine wave to generate a rotating magnetic field in the stator coil, and the rotor is rotationally driven by the action of the rotating magnetic field generated by the stator coil; a storage unit for detecting and storing the sine waves of each phase generated in the converter a correction amount for each phase calculated based on the detection result so that the sine waves of the respective phases coincide with each other; and a correction unit for correcting the switching element based on the calculated correction amount PWM signal for PWM control.

The invention discloses an ESP and EPS combined system for vehicle emergency steering collision avoidance and a control method thereof. The system comprises a sensor unit, a controller unit and an actuator unit. The method comprises the steps that a sensor collects vehicle driving state information, and a longitudinal vehicle speed vx, a front wheel steering angle delta and a road adhesion coefficient mu are obtained; an ECU calculates an expected angular velocity through a two-degree-of-freedom vehicle dynamics model, calculates a maximum yaw velocity for ensuring the stability of the vehicle through a road adhesion limit, judges the misoperation degree of a driver, formulates a coordination control command and assists the driver in operation. A combined control structure strategy based on the ESP and the EPS is provided, coordinated control of the ESP and the EPS is achieved, the potential risk of instability of the vehicle can be reduced under the condition that an emergency steering driver operates mistakenly, the steering operation hand feeling of the driver is improved, and the psychological stress of the driver is reduced.

The invention relates to a cog belt and a belt reduction device including the cog belt. The cog belt includes a back portion and helical teeth on an inner peripheral side of the back portion, and a plurality of the helical teeth are arranged at a fixed pitch onn a belt length direction. The angle ([theta]) between the direction in which a tooth line of the helical tooth (20) extends and the direction of the belt width is higher than 7 degrees and lower than 10 degrees. When thickness of the back portion is represented by tb, the tooth height of the helical tooth (20) is represented by hb, and when the ratio A of tb to hb is calculated by A = 100 x tb / hb, A is 120% or more and 240% or less.

Exemplary embodiments of the present invention relate to a friction compensation logic of MDPS and a friction compensation method using the same. The friction compensation logic of MDPS in accordance with an embodiment of the present invention includes: a signal processor configured to extract only a signal having a limited range from column torque signals input from a column torque; a friction compensation sign calculator configured to determine a friction compensation sign by integrating the column torque signal extracted by the signal processor and calculating the friction compensation sign by limiting the integrated value to a set value; and a friction compensation torque calculator configured to calculate a friction compensation torque by reflecting a friction compensation amount to a value calculated by the friction compensation sign calculator.

A toothed belt (16) comprises a back, and a plurality of helical teeth (2) disposed at a fixed pitch along the direction of the belt length and provided on the inner peripheral side of the back. An angle (theta), formed by the direction in which the tooth trace of a helical tooth extends and the belt width direction, is 7 to 10 degrees. When a ratio (A) is A = 100 x tb / hb, where tb is the back thickness and hb is the tooth height of the helical tooth (20), A is 120% to 240%.

An apparatus for driving a motor driven power steering (MDPS) includes: a first calculation unit (10 configured to calculate a damping force gain based on an MDPS output current; a second calculation unit (20) configured to calculate a damping force using vehicle speed and steering angle speed; and a damping force calculation unit (30) configured to calculate a final damping force using the damping force gain calculated through the first calculation unit and the damping force calculated through the second calculation unit.

The invention relates to a method for determining a rack force (Fr, estcomplrack) for a steer-by-wire steering system (1) for a motor vehicle, wherein the rack force (Fr, estcomplrack) is determined from two components, wherein a first component of the rack force (Fr, estvehicle) is generated in a module for the vehicle model-based estimation of the rack force (15) by means of a vehicle model, anda second component of the rack force (Fr, estrack) is generated in a module for the steering-mechanism-model-based estimation of the rack force (16) by means of a steering-mechanism model.

A clutch device (29) is provided with: a handle-side housing (36) having lock grooves (42) formed in the inner periphery thereof at intervals from each other in the circumferential direction; a tire-side housing (38); lock bars (40) provided to the tire-side housing (38) so as to be capable of moving in the radial direction of the tire-side housing (38) and arranged at intervals from each other in the circumferential direction of the tire-side housing (38); and a forward / backward movement mechanism for moving the lock bars (40) forward and backward in the direction toward the lock grooves (42). The lock bars (40) have a lock bar (403) and a lock bar (401), which are configured so that, when the lock bars (40) are moved toward the lock grooves (42) by the forward / backward movement mechanism, irrespective of the rotational phase difference between the handle-side housing (36) and the tire-side housing (38), the lock bar (403) enters a lock groove (423) of the lock grooves and the lock bar (401) enters a lock groove (421) of the lock grooves.

The invention provides a stiction compensation method and device. The method and device are used for an electric power steering system, and the method comprises the steps that a torque of a steering wheel is acquired from a torque sensor; a stiction compensation current of the electric power steering system is determined according to the torque of the steering wheel; and the rotation of a power motor is controlled according to the stiction compensation current, so that the electric power steering system performs stiction compensation, thereby achieving stiction compensation and reducing fluctuation amplitude values during a steering process, improving steering feel and improving driving safety.

A column-assist type electric power steering device (10) is provided with: a steering shaft (22); a magnetostrictive type torque sensor (80) that detects a torque produced in the steering shaft (22); and bearings (64, 65) that rotatably support the steering shaft (22). The magnetostrictive type torque sensor (80) includes a magnetostrictive film (81) disposed on an outer peripheral surface of the steering shaft (22), and a detection unit (83) that is disposed opposite the magnetostrictive film (81) and that detects a change in permeability. The bearings (64, 65) are installed at two locations in the axial direction of the steering shaft (22) in such a manner as to sandwich the detection unit (83).

A clutch device (29) switches between transmission and non-transmission of rotational force between a steering wheel-side housing (76) and a tire-side housing (78). The clutch device (29) is configured so as to be capable of switching between: a first mode in which rotational force is not transmitted between the steering wheel-side housing (76) and the tire-side housing (78); a second mode in which rotational force can be transmitted to rotation in both directions in a state in which the steering wheel-side housing (76) and the tire-side housing (78) have been mutually locked; a third mode in which, in a state in which rotational force can be transmitted to rotation in one direction between the steering wheel-side housing (76) and the tire-side housing (78), rotation of the steering wheel-side housing (76) or the tire-side housing (78) is allowed in the other direction, whereby transmission of rotational force can be canceled.

The invention relates to a method for operating a steering device which comprises at least one electric motor (10) that can be operated with an increased torque lying between a nominal torque (14) ofthe electric motor (10) and a maximum torque (16) of the electric motor (10) over an entire basic setting range (12). In at least one operating state, a threshold torque (18) of the electric motor (10) is at least temporarily limited to a reduced torque (20), in particular in comparison to the maximum torque (16), at least depending on at least one temperature characteristic variable.

The invention provides an electric power-assisted steering system, a friction compensation method and device, equipment and a medium. The friction compensation method of the electric power-assisted steering system comprises the steps: acquiring a booster friction force of a booster and a steering gear friction force of a steering gear which are measured respectively; calculating a total friction force difference value according to the booster friction force and the steering gear friction force; and compensating the boosting torque of the booster according to the total friction force differencevalue. The friction force compensation performance of the electric power steering system is improved, and the steering hand feeling and the whole vehicle driving experience are improved.

A power steering system provides improved steering feel whenever negligible power assist is required is required such as during on-center operation or at very high vehicular speeds. The power steering system includes fluid lines used for directly coupling a motor driven pump to a power cylinder. The fluid lines are coupled to a system reservoir or to one another whenever a primary control signal indicative of steering wheel torque has a value below a selected threshold value thereby substantially decoupling the power cylinder from the pump.