Abstract: An angle computing device includes a first computing unit configured to compute a rotation angle of a motor based on a detection signal from a detection unit that detects the rotation angle of the motor, and a second computing unit configured to compute turn number information indicating the number of turns of the motor as information used to compute the rotation angle based on the detection signal from the detection unit. When a start switch of a vehicle is off, the first computing unit stops and the second computing unit computes the turn number information. When the start switch is on, the first computing unit computes the rotation angle using the turn number information that is computed by the second computing unit while the start switch is off.

Abstract: A steering system includes a rotation angle sensor that detects a signal related to an absolute steering angle, and an assist circuit that acquires the signal related to the absolute steering angle while an ignition switch is off in order to reduce battery consumption. The assist circuit includes a counter that updates a count value based on a result of detection by a first rotating direction determining unit and a second rotating direction determining unit that determine a rotating direction of a motor, and an abnormality detecting unit that detects an abnormality in absolute steering angle based on a past value and a current value of the count value in the counter.

Abstract: A steering system includes a rotation angle sensor that detects a signal related to an absolute steering angle, and an assist circuit that acquires the signal related to the absolute steering angle while an ignition switch is off in order to reduce battery consumption. The assist circuit includes a counter that updates a count value based on a result of detection by a first rotating direction determining unit and a second rotating direction determining unit that determine a rotating direction of a motor, and an abnormality detecting unit that detects an abnormality in absolute steering angle based on a past value and a current value of the count value in the counter.

Abstract: There is provided an actuator control apparatus configured such that even when an electronic device that generates an electric signal to be used to control an actuator is provided in the form of a duplexed system, an increase in the number of communication paths between the electronic device and a controller is suppressed. A torque sensor and a rotation angle sensor are each provided in the form of a duplexed system. Two sets of a torque sensor and a rotation angle sensor are connected to a microcomputer via a SPI communication line. The torque sensors and the rotation angle sensors are connected to the microcomputer via CS communication lines, respectively. By selecting a communication target via a corresponding one of the CS communication lines, the microcomputer is able to receive multiple kinds of electric signals via each one of the SPI communication lines.

Abstract: There is provided an actuator control apparatus configured such that even when an electronic device that generates an electric signal to be used to control an actuator is provided in the form of a duplexed system, an increase in the number of communication paths between the electronic device and a controller is suppressed. A torque sensor and a rotation angle sensor are each provided in the form of a duplexed system. Two sets of a torque sensor and a rotation angle sensor are connected to a microcomputer via a SPI communication line. The torque sensors and the rotation angle sensors are connected to the microcomputer via CS communication lines, respectively. By selecting a communication target via a corresponding one of the CS communication lines, the microcomputer is able to receive multiple kinds of electric signals via each one of the SPI communication lines.