Method of controlling a windshield wiper system

A method of controlling a vehicular windshield wiping system including at least one wiper blade, and a sensor mounted to the windshield for monitoring a portion of the windshield, the sensor generating a signal having a value which varies as moisture or dirt or both collect on the monitored portion, the wiping system being activated when the sensor value crosses a predetermined switch-on threshold and deactivated when the sensor value is above a predetermined switch off threshold, the method comprising the steps of:

• determining a first sensor value when the monitored portion is substantially free of moisture, the first sensor value being less than a maximum possible sensor value due to the presence of dirt on the monitored portion, thereby allowing the windshield wiping system to distinguish between the presence of moisture and dirt on the monitored portion based on the first sensor value;
• modifying the predetermined switch-on and switch-off thresholds based on the first sensor value;
• and
• controlling the windshield wiping system based on the modified thresholds, thereby insuring the wiping system is activated due only to the presence of moisture on the monitored portion.

A method of controlling a vehicular windshield wiping system including at least one wiper blade, and a sensor mounted to the windshield for monitoring a portion of the windshield, the sensor generating a signal having a value which varies as moisture or dirt or both collect on the monitored portion, the wiping system being activated when the sensor value crosses a predetermined switch-on threshold, and deactivated when the sensor value is above a predetermined switch-off threshold, the method comprising the steps of:

• activating the wiping system for at least one wipe cycle when the sensor value drops below the predetermined switch-on threshold, the at least one wiper blade leaving a resting position and wiping the windshield, passing over the monitored portion of the windshield at least once;
• determining a first sensor value after the at least one wiper blade passes over the monitored portion of the windshield for the last time during the wipe cycle, the monitored portion being substantially free of moisture, the first sensor value being less than a maximum possible sensor value due to the presence of dirt on the monitored portion so as to allow the windshield wiping system to distinguish between the presence of moisture and dirt on the monitored portion;
• modifying the predetermined switch-on and switch-off thresholds based on the first sensor value;
• and
• controlling the windshield wiping system based on the modified thresholds, thereby insuring the wiping system is activated due only to the presence of moisture on the monitored portion.

A method of controlling a vehicular windshield wiping system, the wiping system including at least one windshield wiper and a sensor mounted to the windshield for monitoring a portion of the windshield wiped by the wiper during each wipe cycle, the sensor generating a sensor signal having a value which varies as a coating collects on the monitored portion of the windshield, the method comprising the steps of:

• defining a connection threshold based on the sensor signal, for starting operation of the windshield wiping system;
• defining a first disconnection threshold based on the sensor signal, for ceasing operation of the windshield wiping system in a first mode of operation;
• and
• defining a second disconnection threshold based on the sensor signal, for ceasing operation of the windshield wiping system in a second mode of operation.

A method of controlling a vehicular windshield wiping system including a motor, at least one windshield wiper and an optoelectronic sensor mounted to the windshield for monitoring a portion of the windshield wiped by the wiper during each wipe cycle, the sensor including infrared beam transmitters for emitting beams and infrared beam receivers for receiving the emitted beams, the emitted beams being modified based on the coating on the windshield, the sensor generating a signal having a value which varies as a coating collects on the monitored portion of the windshield, the method comprising the steps of:

• establishing a data window having a first plurality of values based on the sensor signal;
• establishing a measurement range within the data window, the measurement range having a second plurality of values defined by an upper threshold and a lower threshold;
• and
• modifying the amplification of the beams emitted by the beam transmitters if the sensor signal has a value which is outside of the measurement range.

A method of controlling a vehicular windshield wiping system including a motor, at least one windshield wiper and an optoelectronic sensor mounted to the windshield for monitoring a portion of the windshield wiped by the wiper during each wipe cycle, the sensor including infrared beam transmitters for emitting beams and infrared beam receivers for receiving the emitted beams, the emitted beams being modified based on the coating on the windshield, the sensor generating a sensor signal having a value which varies as a coating collects on the monitored portion of the windshield, the method comprising the steps of:

• establishing a data window based on the sensor signal, the data window having a first plurality of values defined by an upper boundary and a lower boundary;
• establishing a measurement range within the data window, the measurement range having a second plurality of values defined by an upper threshold and a lower threshold;
• modifying the amplification of the beams emitted by the beam transmitters if the sensor signal has a value which is outside of the measurement range when the motor is deactivated;
• and
• modifying the amplification of the beams emitted by the beam transmitters if the sensor signal has a value which is outside of the data window when the motor is activated.