Abstract: An assisting command value calculating unit calculates a first assisting factor on the basis of the value of a torque differential control volume added to a basic assist control volume based on a steering torque value, while increasing or decreasing, on the basis of an assisting gradient, the torque differential control volume based on a torque differential value. The pinion angle F/B control unit calculates a pinion angle command value, capable of being converted to a steering angle of the steering wheel, on the basis of the steering torque and the first assisting factor, and executes rotational angle feedback control. The assisting command value calculating unit calculates an assisting command value on the basis of the value of a second assisting factor, calculated by the pinion angle F/B control unit, added to the first assisting factor.

Abstract: A steering torque shift control amount calculation unit (31) calculates the steering torque shift control amount (?ts) by multiplying the basic shift amount (?ts_b) used as the basic compensation component by the transition coefficient (Kss). Then, the steering torque shift control amount (?ts) is subjected to the low-pass filter process in an abrupt change prevention processing unit (32). An abrupt change prevention processing unit (40) is provided in the steering torque shift control amount calculation unit (31). The transition coefficient (Kss) is subjected to the low-pass filter process in the abrupt change prevention processing unit (40). The cutoff frequency of the low-pass filter that forms the abrupt change prevention processing unit (40) is set to a value lower than the cutoff frequency of the low-pass filter that forms the abrupt change prevention processing unit (32) that executes the low-pass filter process on the torque shift control amount (?ts).

Abstract: A sensor element detects exhaust gas emitted from an internal combustion engine. A heater is supplied with electricity from a power source so as to heat the sensor element. A detection unit detects heater voltage across the heater. A degradation determination unit determines whether the heater is degraded in accordance with at least one of the heater voltage and a diagnosis value, which changes according to the heater voltage. The degradation determination unit determines whether the heater is degraded further in accordance with at least one of power-supply voltage of the power source and a driving state of an electric device, which is supplied with electricity from the power source.

Abstract: In an engine of a direct-injection type, a split injection (a fuel injection in an intake stroke and a fuel injection in a compression stroke) is carried out. A compression-stroke injection amount is gradually decreased or increased when the split injection is carried out. Engine rotational speed, which varies by combustion of such injected fuel, is detected for respective fuel injection amounts, which are varied (decreased or increased) as above. Such a fuel injection amount, with which the engine rotational speed becomes maximum, is calculated and set as a basic injection amount for the compression-stroke injection. The fuel injection in the compression stroke is then controlled based on the basic injection amount.

Abstract: An electric power steering (EPS) apparatus 1 includes a motor 12, an EPS actuator 10, a torque sensor 14, and an ECU 11. The EPS actuator 10 uses the motor 12 as a drive source to apply assist force to a steering system, thereby assisting a steering operation. The torque sensor 14 detects a steering torque ? of the steering system. The ECU 11 controls the operation of the EPS actuator 10. Based on the steering torque ? detected by the torque sensor 14, the ECU 11 computes a basic shift amount ?ts_b of the assist force applied to the steering system. The ECU 11 determines which one of returning, holding, and turning is the state of the steering operation. When the state of the steering operation is returning or holding, the ECU 11 executes compensation control for correcting the steering torque ?, which is used in the computation of the basic shift amount ?ts_b of the assist force, thereby increasing the assist force applied to the steering system.

Abstract: A current command value computing section includes an integration control computing section. Based on an integration of the steering torque ?, the integration control computing section computes a steering torque integration control amount Iint*, which is a compensation component for increasing the assist force. The integration control computing section functions as a determining device that determines whether the vehicle is traveling forward in a straight line. When the determining device determines that the vehicle is traveling forward in a straight line, the integration control computing section outputs the steering torque integration control amount Iint* to an adder. The current command value computing section superimposes the steering torque integration control amount Iint* on a basic assist control amount Ias* computed by a basic assist control section, and outputs the obtained value, as a current command value Iq* corresponding to a target assist force, to an output section.

Abstract: A steering torque shift control amount calculation unit (31) calculates the steering torque shift control amount (?ts) by multiplying the basic shift amount (?ts_b) used as the basic compensation component by the transition coefficient (Kss). Then, the steering torque shift control amount (?ts) is subjected to the low-pass filter process in an abrupt change prevention processing unit (32). An abrupt change prevention processing unit (40) is provided in the steering torque shift control amount calculation unit (31). The transition coefficient (Kss) is subjected to the low-pass filter process in the abrupt change prevention processing unit (40). The cutoff frequency of the low-pass filter that forms the abrupt change prevention processing unit (40) is set to a value lower than the cutoff frequency of the low-pass filter that forms the abrupt change prevention processing unit (32) that executes the low-pass filter process on the torque shift control amount (?ts).

Abstract: When engine rotation speed is increasing in a compression stroke injection mode, a control device determines that a crank angle at injection end timing of an injector deviates toward a delayed crank angle side and performs additional ignition at timing when (or immediately before or after) a crank angle at actual injection end timing of the injector of a present injection cylinder is reached. Thus, even when the crank angle at the injection end timing deviates toward the delayed crank angle side with respect to preset original ignition timing, a combustion state can be stabilized by performing the additional ignition at timing, at which a suitable stratified mixture gas is formed in a cylinder, through the execution of the additional ignition at the timing substantially the same as the actual injection end timing.

Abstract: An electric power steering (EPS) apparatus 1 includes a motor 12, an EPS actuator 10, a torque sensor 14, and an ECU 11. The EPS actuator 10 uses the motor 12 as a drive source to apply assist force to a steering system, thereby assisting a steering operation. The torque sensor 14 detects a steering torque ? of the steering system. The ECU 11 controls the operation of the EPS actuator 10. Based on the steering torque ? detected by the torque sensor 14, the ECU 11 computes a basic shift amount ?ts_b of the assist force applied to the steering system. The ECU 11 determines which one of returning, holding, and turning is the state of the steering operation. When the state of the steering operation is returning or holding, the ECU 11 executes compensation control for correcting the steering torque ?, which is used in the computation of the basic shift amount ?ts_b of the assist force, thereby increasing the assist force applied to the steering system.

Abstract: A sensor element detects exhaust gas emitted from an internal combustion engine. A heater is supplied with electricity from a power source so as to heat the sensor element. A detection unit detects heater voltage across the heater. A degradation determination unit determines whether the heater is degraded in accordance with at least one of the heater voltage and a diagnosis value, which changes according to the heater voltage. The degradation determination unit determines whether the heater is degraded further in accordance with at least one of power-supply voltage of the power source and a driving state of an electric device, which is supplied with electricity from the power source.

Abstract: When engine rotation speed is increasing in a compression stroke injection mode, a control device determines that a crank angle at injection end timing of an injector deviates toward a delayed crank angle side and performs additional ignition at timing when (or immediately before or after) a crank angle at actual injection end timing of the injector of a present injection cylinder is reached. Thus, even when the crank angle at the injection end timing deviates toward the delayed crank angle side with respect to preset original ignition timing, a combustion state can be stabilized by performing the additional ignition at timing, at which a suitable stratified mixture gas is formed in a cylinder, through the execution of the additional ignition at the timing substantially the same as the actual injection end timing.

Abstract: A rotation speed calculation interval is set near a combustion top dead center of each cylinder of an engine. An interval rotation time necessary for a crankshaft to rotate through the rotation speed calculation interval is calculated as angular speed information of the crankshaft in the rotation speed calculation interval for each combustion stroke of the engine. Engine rotation speed is calculated based on the interval rotation time. The angular speed information of the crankshaft in the rotation speed calculation interval set near the combustion top dead center reflects a combustion state or generated torque. By calculating the engine rotation speed based on the angular speed information, the engine rotation speed highly correlated with the combustion state or the generated torque of the engine can be calculated.

Abstract: An individual-cylinder air-fuel ratio estimation model is designed so as to consider the mixing of gases exhausted from adjacent combustion cylinders, and a movement by which a mixed gas arrives at the position of an air-fuel ratio sensor, in order that influences ascribable to the intervals (combustion intervals) of the adjacent combustion cylinders may be reflected on the estimation values of individual-cylinder air-fuel ratios. In evaluating the mixing of the gases which are exhausted from the adjacent combustion cylinders, there are considered the lengths and shapes of the exhaust manifolds of the respective combustion cylinders. In evaluating the movement by which the mixed gas arrives at the position of the air-fuel ratio sensor, there are considered a distance or volume from the confluence to the position of the air-fuel ratio sensor, and the exhaust gas quantities of the respective combustion cylinders.

Abstract: An individual-cylinder air-fuel ratio estimation model is designed so as to consider the mixing of gases exhausted from adjacent combustion cylinders, and a movement by which a mixed gas arrives at the position of an air-fuel ratio sensor, in order that influences ascribable to the intervals (combustion intervals) of the adjacent combustion cylinders may be reflected on the estimation values of individual-cylinder air-fuel ratios. In evaluating the mixing of the gases which are exhausted from the adjacent combustion cylinders, there are considered the lengths and shapes of the exhaust manifolds of the respective combustion cylinders. In evaluating the movement by which the mixed gas arrives at the position of the air-fuel ratio sensor, there are considered a distance or volume from the confluence to the position of the air-fuel ratio sensor, and the exhaust gas quantities of the respective combustion cylinders.

Abstract: An individual-cylinder air-fuel ratio estimation model is designed so as to consider the mixing of gases exhausted from adjacent combustion cylinders, and a movement by which a mixed gas arrives at the position of an air-fuel ratio sensor, in order that influences ascribable to the intervals (combustion intervals) of the adjacent combustion cylinders may be reflected on the estimation values of individual-cylinder air-fuel ratios. In evaluating the mixing of the gases which are exhausted from the adjacent combustion cylinders, there are considered the lengths and shapes of the exhaust manifolds of the respective combustion cylinders. In evaluating the movement by which the mixed gas arrives at the position of the air-fuel ratio sensor, there are considered a distance or volume from the confluence to the position of the air-fuel ratio sensor, and the exhaust gas quantities of the respective combustion cylinders.

Abstract: A reference model simulates a desired response characteristic of the variable valve timing apparatus and is constructed by using a dynamic characteristic in a region of the maximum changing speed of the valve timing of the variable valve timing apparatus. The variable valve timing apparatus is constructed of the control system with two degrees of freedom in which in the controller, the feedback duty is calculated so that the deviation between the output obtained by applying the time delay to the output of the quickest response model and the valve timing is small, and in the reverse VCT model, the feed forward duty is calculated so that the target advance amount is realized based upon the output of the quickest response model, and the control duty of the variable valve timing apparatus is obtained by addition of the feedback duty and the feed forward duty.

Abstract: A rotation speed calculation interval is set near a combustion top dead center of each cylinder of an engine. An interval rotation time necessary for a crankshaft to rotate through the rotation speed calculation interval is calculated as angular speed information of the crankshaft in the rotation speed calculation interval for each combustion stroke of the engine. Engine rotation speed is calculated based on the interval rotation time. The angular speed information of the crankshaft in the rotation speed calculation interval set near the combustion top dead center reflects a combustion state or generated torque. By calculating the engine rotation speed based on the angular speed information, the engine rotation speed highly correlated with the combustion state or the generated torque of the engine can be calculated.

Abstract: When a specified air-fuel ratio F/B control condition is established during supply of a secondary air provided, an air-fuel ratio F/B control is executed, and at this time, an initial value of a target air-fuel ratio is set to a before-catalyst air-fuel ratio detected by an A/F (air-fuel ratio) sensor. The target air-fuel ratio subsequent to this is gradually changed from the initial value to a specified air-fuel ratio. By this, the initial value of the target air-fuel ratio can be suitably set at a start time of execution of the air-fuel ratio F/B control during the supply of the secondary air. The target air-fuel ratio subsequent to this is gradually changed to a stoichiometric air-fuel ratio, so that a change in engine rotation speed is suppressed and the drivability can be improved.

Abstract: An air-fuel ratio sensor detects an air-fuel ratio of an exhaust gas at a confluent portion of an exhaust gas. An air-fuel ratios in each cylinder are estimated to be controlled based on an output of the air-fuel ratio sensor. A computer determines whether an air-fuel detecting timing deviates according to a dispersion of the estimated air-fuel ratio among cylinders. When the deviation is detected, the air-fuel ratio detecting timing is varied to estimate an air-fuel ratio before and after correcting amount of fuel. The air-fuel ratio detecting timing is adapted as a proper timing when the variation amount of the estimated air-fuel ratio before and after the correction of fuel amount corresponds to the correct amount of fuel.

Abstract: A reference model simulates a desired response characteristic of the variable valve timing apparatus and is constructed by using a dynamic characteristic in a region of the maximum changing speed of the valve timing of the variable valve timing apparatus. The variable valve timing apparatus is constructed of the control system with two degrees of freedom in which in the controller, the feedback duty is calculated so that the deviation between the output obtained by applying the time delay to the output of the quickest response model and the valve timing is small, and in the reverse VCT model, the feed forward duty is calculated so that the target advance amount is realized based upon the output of the quickest response model, and the control duty of the variable valve timing apparatus is obtained by addition of the feedback duty and the feed forward duty.