Abstract: A servo pattern recording device capable of improving the recording accuracy of a servo pattern. The servo pattern recording device is comprised of a magnetic head that records a servo pattern for tracking servo on a magnetic tape, a first motor that feeds the magnetic tape, a second motor that takes up the magnetic tape, and a main panel along a surface of which the magnetic tape is caused to move. The first motor and the second motor are mounted on the main panel, and the magnetic head is mounted on a first sub panel that is formed separately from the main panel and is connected to the main panel via a connecting member.

Abstract: A vehicle driving force control device controls engine torque so as to correct driver's request-engine-torque with the torque-down amount by an engine control unit, the torque-down amount being set into the lower one of a first torque-down amount and a second torque-down amount by a control-amount setting unit, the first torque-down amount being calculated on the basis of a relation between a tire force generated on a tire and a maximum tire force which the tire is capable of exercising against a current road-surface by a first traction control unit, the second torque-down amount being calculated on the basis of a slip rate of the tire by a second traction control unit.

Abstract: A main controller calculates permissible driving forces of individual wheels from a road-surface friction coefficient, ground loads of the individual wheels, and lateral forces of the individual wheels. The main controller then calculates a permissible engine torque on the basis of the calculated permissible driving forces so as to limit engine output. In addition, based on the calculated permissible driving forces, the main controller calculates a transfer-clutch torque for front-rear driving-force distribution control, a rear-wheel torque shift amount for left-right driving-force distribution control, and a steering-angle correction amount for steering-angle control.

Abstract: An driving assist control unit controls actuators such as a front wheel steering device, an accelerator pedal mechanism, an alarm lamp. The control units estimates permissible tire-force being capable of acting on the vehicle tire on the basis of road-surface friction coefficient and ground load of the tire, and then calculates tire-force margin by subtracting current tire-force currently acting on the tire, such as total driving force and lateral force, from the permissible tire-force. The control unit then controls steering reaction force of the front wheel steering device, reaction force of the accelerator pedal, and flashing frequency of the alarm lamp in accordance with the magnitude of the tire-force margin, respectively.

Abstract: A braking-force control device has a brake control function for performing brake control on a front outside wheel when a vehicle is detected to be in an oversteer condition during a turning operation and for performing brake control on a rear inside wheel when the vehicle is detected to be in an understeer condition during a turning operation. For preventing the oversteer condition, a command for reducing the engine torque is output. On the other hand, for preventing the understeer condition, the engine torque is limited in accordance with a permissible engine torque value that is calculated on the basis of a road-surface friction coefficient, and ground loads and lateral tire forces of individual wheels. If it is detected that engine braking is in operation, the engine torque is adjusted to substantially zero.

Abstract: A driving force control device includes an individual-wheel friction-circle limit-value calculating portion that calculates friction-circle limit-values of individual wheels, an individual-wheel requested-resultant-tire-force calculating portion that calculates requested resultant tire forces of the individual wheels, an individual-wheel resultant-tire-force calculating portion that calculates resultant tire forces of the individual wheels, an individual-wheel requested-excessive-tire-force calculating portion that calculates requested excessive tire forces of the individual wheels, an individual-wheel excessive-tire-force calculating portion that calculates excessive tire forces of the individual wheels, an excessive-tire-force calculating portion that calculates an excessive tire force, an over-torque calculating portion that calculates an over-torque, and a control-amount calculating portion that calculates a control amount that is output to an engine control unit.

Abstract: Steering stability of a vehicle under a traveling state such as cornering is enhanced by controlling a state of the vehicle based on cornering powers of right and left wheels. A detecting unit 1 detects action force containing longitudinal force Fx, lateral force Fy and vertical force Fz which act on each wheel. A specifying unit 2 specifies a friction coefficient between the wheels and road surface. An estimating unit 6 estimates cornering power ka of each wheel based on the action force and the friction coefficient. A processing unit 7 determines control values so that the representative value ka_ave of the cornering powers concerning the right and left wheels is larger than the present value of the representative value ka_ave of the cornering powers concerning the right and left wheels. Controlling units 8 to 10 control the state of the vehicle based on the control values thus determined.

Abstract: The present invention relates to active chassis systems and a method, a system and a computer program product for road to wheel friction estimation (RFE). More specifically, the present invention relates to a method, a system and computer program product for estimating, with especially high accuracy, the road surface friction coefficient (?). Said method comprises the steps of: continuously estimating a road surface friction coefficient (?), using an algorithm based on a dynamic model of the vehicle, determining a road surface friction coefficient range based on specific transient or static vehicle driving parameters, and reinitiating said algorithm so that the estimated road surface friction coefficient (?) is adapted to said determined road surface friction coefficient range. Said system comprises means for performing the steps of said method. Said computer program product comprises code for execution of the steps of said method.

Abstract: With a drive power distribution control section, limited differential torque correction value TLSDS is estimated and calculated by a limited differential torque correction value calculating section based on input torque TCD. Also, a transfer torque calculating section calculates transfer torque TLSD2 by multiplying input torque sensing transfer torque TLSD1 by vehicle slip angular velocity correction coefficient K(d?/dt). A transfer torque correction/output section then subtracts limited differential torque correction value TLSDS from the transfer torque TLSD2 to calculate and output transfer torque TLSD. In this way, clutch engaging torque for carrying out front and rear drive power distribution is set with good accuracy, and it is possible to have both high cornering performance and high traction performance.

Abstract: An adjustment unit identifies a front-rear driving force distribution control unit and a braking force control unit, and calculates based on the current vehicle state, a target yaw moment required for each of the front-rear driving force distribution control unit and braking force control unit. Then, based on the current operating state of each of the control units, a control correction value for each unit is calculated in consideration of the maximum value, and outputted.

Abstract: A steering control section has a first steering angle correction amount calculating section, a second steering angle correction amount calculating section, and a motor rotational angle calculating section. The first correction amount calculating section calculates a first correction amount based on a vehicle speed and an actual steering wheel angle. The second correction amount calculating section calculates a second correction amount through multiplying a control gain corresponding to the vehicle speed with a value calculated by low-pass filtering a differential value of steering wheel angle. The motor rotational angle calculating section calculates a motor rotational angle corresponding to the value adding the first and second steering angle correction amount, and outputs it to a motor driving section so as to drive an electric motor for correcting the steering angle. Thereby, an unstable vehicle behavior due to a resonance of a yaw motion caused in the steering operation can be suppressed.

Abstract: A drive power distribution control section calculates input torque sensing transfer torque by first transfer torque calculating section, steering angle/yaw rate sensing transfer torque by second transfer torque calculating section, and tack-in prevention transfer torque by third transfer torque calculating section. At this time, input torque sensing transfer torque is estimated using respective time constants for increasing and decreasing engine torque. Also, in a region where input torque is large, a variation amount is increased. The steering angle/yaw rate sensing transfer torque corrects yaw moment, and in correction of an absolute value of the yaw moment towards a larger value a limit is provided based on a previous correction result.

Abstract: A temporary indicated torque is obtained by taking a conventional dead zone area for a first slip control area, and the value proportional to the slip quantity for a maximum value, this temporary indicated torque is corrected by a correction value according to the tight cornering brake quantity to be the indicated torque of the transfer clutch, and occurrence of any tight cornering brake phenomenon is prevented thereby. In a slip control area after passing a dead zone area (a second slip control area), the slip control is smoothly transferred from the first slip control area to the second slip control area by performing the slip control with a value of the indicated torque according to the slip quantity added to the indicated torque in the first slip control area as the indicated torque, abrupt torque change is prevented, and the vehicle behavior is stabilized thereby.

Abstract: A correlation coefficient computing unit receives front-left and front-right wheel-accelerations from high-pass filters, each having a driver-operating component removed therefrom, and computes a correlation coefficient therebetween. A computing-unit of upper and lower limits of a correlation coefficient of a population sets upper and lower limits of a correlation coefficient of a population. First and second correction-gain setting units set first and second correction-gains varying in accordance with running and driving states, respectively. A correlation coefficient computing unit of a population computes a correlation coefficient of a population of this time based on the correlation coefficients computed as above, a correlation coefficient of a population of the previous time, the upper and lower limits, and the first and second correction-gains.

Abstract: A driving force distribution control unit 60 calculates front/rear driving force distribution cooperative control addition yaw moment by multiplying front/rear driving force distribution control addition yaw moment by a front/rear driving force distribution cooperative control gain. Under steering accelerating condition, when it is possible to judge that actual lateral acceleration is high and the road is a high ? road, the front/rear driving force distribution cooperative control gain is set to become a low control gain so as to reduce a control amount by the front/rear driving force distribution control operation. Also, the driving force distribution control unit 60 calculates right/left driving force distribution cooperative control addition yaw moment by multiplying right/left driving force distribution control addition yaw moment by a right/left driving force distribution cooperative control gain.

Abstract: To provide a new vehicle control technique, a calculation section calculates a cornering power ka using the detected longitudinal force Fx, lateral force Fy, and vertical force Fz, and the identified friction coefficient ?. This calculation is made based on the correlation between a slip angle ? of the wheels and the lateral force Fy. Based on thus calculated cornering power ka and a target cornering power ka? required for the wheels, a processing section determines a change amount for changing at least one action force out of the longitudinal force Fx, the lateral force Fy, and the vertical force Fz, all acting on the wheels. Based on thus determined change amount, a control section controls at least one action force out of the longitudinal force Fx, the lateral force Fy, and the vertical force Fz, all acting on the wheels.

Abstract: A drive power from an engine is transferred to front wheel drive systems and rear wheel drive systems via a central differential. A torque distribution ratio between front and rear wheels defined by the central differential is set to one for the front wheels being made too much thereof, with a motor generator being coupled to the rear wheel drive systems. In response to detection signals from various sensors for detecting the running conditions, a drive power control unit controls the additional torque from the motor generator toward the drive torque or regenerative braking torque side, thereby changing the torque distribution ratio between the front and rear wheels. Thus, a degree of flexibility in making a change in the torque distribution between front and rear wheels or between right and left wheels is increased, thereby realizing an all-wheel drivable hybrid vehicle which provides further improved running performance.

Abstract: A mode establishing section of a differential limiting control apparatus for a four wheel drive vehicle commands an automatic mode control section or a manual mode control section to output calculated clutch torques according to a signal from a mode switch operated by a driver. In an initial condition of an ignition switch turned on, the execution command is issued to the automatic mode control section, until the driver newly selects the manual mode through the mode switch. Further, when the vehicle travels at a speed higher than a preestablished threshold value, the execution command is outputted to the automatic mode control section, irrespective of the signal from the mode switch.

Abstract: An estimating unit 7 estimates an element aij of a system matrix based on state quantity including at least a longitudinal force Fx applied to a wheel, a vertical force Fz applied to the wheel and a vehicle speed V. A setting unit 8 sets a target value aij? regarding the element aij of the system matrix. A processing unit 9 calculates a control value so that the estimated element aij approaches the set target value aij?. Controlling units 10 to 13 control a vehicle based on the calculated control value. Here, the element aij is expressed by a sum of a linear term changing with linearity of the wheel and a nonlinear term changing with nonlinearity of the wheel, and the setting unit 8 sets the linear term of the element aij as the target value aij?.

Abstract: A drive power from an engine is transferred to front wheel drive systems and rear wheel drive systems via a central differential. A torque distribution ratio between front and rear wheels defined by the central differential is set to one for the front wheels being made too much thereof, with a motor generator being coupled to the rear wheel drive systems. In response to detection signals from various sensors for detecting the running conditions, a drive power control unit controls the additional torque from the motor generator toward the drive torque or regenerative braking torque side, thereby changing the torque distribution ratio between the front and rear wheels. Thus, a degree of flexibility in making a change in the torque distribution between front and rear wheels or between right and left wheels is increased, thereby realizing an all-wheel drivable hybrid vehicle which provides further improved running performance.