Yamaha Hatsudoki Kabushiki Kaisha

Tomoaki Kishi

Takeshi Matsuda

Masato Yokoi

Keisuke Maruo

Naoya Yamaguchi

Mikiyasu Uchiyama

Ichikai Kamihira

Hiroto Watanabe

Haruhiko Samoto

Hiroshi Kobayashi

Risa Yasukawa

Hoshimi Torigoe

An electronic throttle valve control system prevents rapid rotation of a throttle valve when the control system has a failure. A throttle valve controls the amount of intake air to an internal combustion engine, an electric motor drives the throttle valve, and a control section controls the electric motor. The throttle valve has an urging mechanism for urging the throttle valve in the closing direction. The control section shifts the electric motor to a regenerative mode when the control system has a failure to control the speed at which the throttle valve is rotated in the closing direction by the urging force of the urging mechanism. The throttle valve is therefore rotated slowly in the closing direction by the urging force of the urging mechanism and then held in a predetermined opening position.

Electronic throttle valve control system and two-wheeled motor vehicle

An electronic throttle valve control system prevents rapid rotation of a throttle valve reliably when the control system has a failure. A throttle valve controls the amount of intake air to an internal combustion engine, an electric motor drives the throttle valve, and a rotational speed reduction mechanism reduces the rotation of the electric motor to control the rotation of the throttle valve. An urging mechanism urges the throttle valve in the closing direction. An attenuation mechanism attenuates the speed at which the throttle valve is rotated in the closing direction by the urging mechanism when the control system has a failure. The attenuation mechanism is the electric motor in a regenerative mode or an air damper.

An abnormality monitoring device monitors a PWM driving signal output from a driving section of an associated motor control system to judge whether the driving section is operating abnormally. By monitoring the output of the driving section, the monitoring device can detect an abnormality of the driving section before the motor can respond to the abnormal drive signal to a significant degree (e.g., to a degree readily discernable to a rider of a motorcycle on which the motor control system is employed in combination with an electronic throttle system).

Abnormality monitoring device for motor control system

An engine speed control apparatus includes a throttle valve for adjusting the amount of an intake air sucked into an engine, a drive unit for driving the throttle valve, and a control unit for generating a PWM signal for driving the drive unit. The control unit includes a real speed detecting unit for detecting a real engine speed, a target speed setting unit for setting a target engine speed, a target speed change amount calculating unit for calculating a target engine speed change amount with the use of the real engine speed and the target engine speed, and a PWM pulse generating unit which calculates, according to the target engine speed change amount, a PWM control parameter for determining a PWM duty, and generates a PWM signal based on the calculated PWM control parameter, so as to supply the generated PWM signal to the drive unit. The PWM control parameter includes at least one of a PWM duty correction value for correcting the duty ratio of a PWM signal, a PWM duty correction value maintaining time during which the PWM duty correction value is continuously applied, and a PWM duty correction frequency at which the PWM duty correction value is applied.

Engine speed control apparatus; engine system, vehicle and engine generator each having the engine speed control apparatus; and engine speed control method

An electronic engine control unit for a motorcycle or other two-wheeled vehicle gradually decreases engine torque at the time of a failure so as to eliminate an uneasy feeling that an operator might experience if the engine torque were to be reduced abruptly. When a failure is detected, a throttle valve is closed gradually by initially closing the valve quickly and then slowly closing the valve so as to obtain a smooth decrease in engine torque. In addition, the ignition timing is changed gradually toward retardation to gradually decrease engine torque. Alternatively, the ignition pulses to the cylinders are thinned out gradually to cause a gradual decrease in engine torque. As a further alternative in the case of a multi-cylinder engine, the ignition pulses are stopped on a cylinder-by-cylinder basis to cause a gradual decrease in engine torque.

Electronic engine control device

Efficiency of evolution in optimization method is improved using evolutionary computing to obtain individuals of higher suitability by repeating the steps of: forming one generation with a group of individuals, and performing calculation using individuals of at least said generation to create a group of individuals of the next generation. The method is characterized in that a search area for next generation individuals is provided in a selection space and a group of next generation individuals is created within the search area.

Method for controlling machine with control module optimized by improved evolutionary computing

Optimization control of a control system by improving evolution efficiency while retaining the advantages of genetic optimization is described. An optimizer for evolving control parameters affecting the characteristics of a control system uses actual user fitness evaluations of various control parameters or control parameters arranged as chromosomes. Parameters or chromosomes for a next generation are pre-processed using an evaluation model that estimates the fitness of new chromosomes before the chromosomes are presented to the user. Chromosomes that have a low estimated fitness value are modified or deleted, thereby reducing the number of low-quality chromosomes evaluated by the user.

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Shizuoka, Japan

Tomoaki Kishi