Patent Description:
The present invention relates to a wiper and wash system, and more specifically to the monitoring of aircraft windscreen wiper blade usage and health.

Windscreen wiper and wash systems are used to clean and remove the debris from the windscreen. These windscreen wiper and wash systems can be equipped on different types of vehicles including aircraft, automobiles, and marine vehicles. The size and operation of the windscreen wiper and wash systems can vary depending on its application, and the operation of the windscreen wiper and wash system can be controlled by an operator. For example, the speed of the wiper system and the number of wash cycles can be selected and controlled by the operator. These aircraft wipers are controlled by pilot/copilot controls for start, stop, and speed control based on external environmental conditions to which the screen of the aircraft is exposed. <CIT> relates to a windshield wiper device.

According to an embodiment, a method for monitoring a wiper system is provided as claimed in claim <NUM>. The method includes reading a radio frequency identification (RFID) tag embedded in a wiper blade using a reader; comparing the read RFID tag to stored wiper blade information; determining a blade usage ratio for the wiper blade based on determining whether the wiper blade has been replaced; and providing an indication of a status of the wiper blade based at least in part on the blade usage ratio.

In addition to one or more of the features described herein, or as an alternative, further embodiments include responsive to an unsuccessful reading of the RFID tag, providing a fault indication.

In addition to one or more of the features described herein, or as an alternative, further embodiments include responsive to determining the wiper blade has been replaced, resetting the blade usage, otherwise continuing to increment the blade usage for the wiper blade.

In addition to one or more of the features described herein, or as an alternative, further embodiments include a status that is determined by comparing the blade usage ratio to a blade usage ratio threshold.

In addition to one or more of the features described herein, or as an alternative, further embodiments include a blade usage ratio is determined from the following equation: <MAT> wherein the current blade usage is at least one of a duration of time the wiper blade is operated or a number of sweeps the wiper blade is operated, and wherein the blade replacement interval is a configurable interval based on an expected life of the wiper blade.

In addition to one or more of the features described herein, or as an alternative, further embodiments include illuminating a corresponding LED based on comparing the blade usage ratio to a blade usage ratio threshold.

In addition to one or more of the features described herein, or as an alternative, further embodiments include responsive to installing a new wiper blade, storing the RFID of the new wiper blade; and resetting the total duty cycle stored for new wiper blade.

According to an embodiment, a system is provided as claimed in claim <NUM>, the system comprising one or more wiper blades; an electronic control unit configured to monitor the one or more wiper blades and determine a health status of the one or more wiper blades; and a radio-frequency identification (RFID) tag embedded in the one or more wiper blades, wherein the system is configured to perform the method of claim <NUM>.

In addition to one or more of the features described herein, or as an alternative, further embodiments include a motor control unit that is configured to drive the one or more wiper arms and is coupled to the ECU, wherein the ECU is configured to monitor a duty cycle for each mode of operation of the wiper system.

In addition to one or more of the features described herein, or as an alternative, further embodiments include an LED indicator system that is configured to provide an indication of the health status of the one or more wiper blades.

In addition to one or more of the features described herein, or as an alternative, further embodiments include an ECU that is configured to automatically detect a replaced wiper blade based on the RFID tag.

In addition to one or more of the features described herein, or as an alternative, further embodiments include an interface to communicate with a ground maintenance server or cockpit for preventive maintenance to indicate a health status of the one or more wiper blades.

In addition to one or more of the features described herein, or as an alternative, further embodiments include a scanner configured to read the embedded RFID tag.

Aircraft are equipped with wipers to perform cleaning of the windscreen surface through wiper blades to prevent the accumulation of rain, dust, snow, insects, etc. Faulty wipers can cause visibility problems and can cause delays of operation due to unscheduled maintenance.

Currently, there are no mechanisms available to track the duration of usage of the wiper blades and also the duration from the installation date leading to sudden failures. In addition, current wiper systems do not have any wiper blade health and usage monitoring systems for the pilot or maintenance crew which can provide information indicating worn-out blades and potential field failures that can hamper the windscreen visibility.

Inspections are performed manually by visually inspecting the wiper blades, and the wiper blades degrade over a period of time and become non-functional. The low-speed operation can provide longer life while high-speed operation and heavy usage of the wiper blades can reduce its life. Lack of automatic techniques to identify failures in the wiper system may cause the airlines to delay/cancel the flights due to the unscheduled maintenance. The techniques described herein provide for the life history of the wiper blade for easy maintenance and avoids the unnecessary replacement of wiper blades.

<FIG> depicts a high-level architecture of the windscreen wiper and wash system <NUM>. The system <NUM> includes a pilot wiper system <NUM> and a co-pilot wiper system <NUM>. Each of the wiper systems <NUM> and <NUM> include an arm, blade and spray bar <NUM>, <NUM>; gearbox/converter <NUM>, <NUM>, brushless motor, motor drive, and motor control unit (MCU) <NUM>, <NUM>; and an electronic control unit <NUM>, <NUM>.

In addition, the system <NUM> also includes a wash system <NUM>. The wash system <NUM> includes a wash tank and a wash fluid level sensor. The wash tank stores the wash fluid used when the wiper system is activated and is provided to the spray bar <NUM>, <NUM> through the wash tubes <NUM>. The level of the wash fluid in the wash tank is sensed using the fluid level sensor installed in the wash tank. In the event a low fluid level or below predefined threshold in the wash tank is detected, a fault can be reported to the wiper systems. The wiper system can further transmit the fault to the cockpit to alert the operators.

The system <NUM> includes avionics systems <NUM> and communicate with the pilot and co-pilot wiper systems via the aircraft avionics bus <NUM>. The avionics systems <NUM> address both wiper systems independently using their assigned unique addresses. In addition, the avionics systems <NUM> implement logic to dynamically communicate and configure the wiper parameters (wiper speed, sweep angle, sweep area, wash control, wiper control, etc.). The avionics systems <NUM> are also configured to retrieve the maintenance fault logs from the fault log repository in the wiper system. The avionics system <NUM> can also monitor the wiper and wash systems status.

The system <NUM> also includes a cockpit I/O <NUM> which is configured to receive faults that may be encountered in the wiper system and the low-level wash fluid status. The cockpit I/O <NUM> also provides cockpit input to the wiper and wash systems such as setting the operational mode, wiping speed, washing operation, etc..

The aircraft avionics communication bus <NUM> can include wired communication interface such as ARINC <NUM>, CAN, Ethernet, RS422/RS232, etc. or a wireless communication interface such as Bluetooth, Wi-Fi, wireless avionics intra-communication (WAIC), etc..

<FIG> depicts a detailed architecture of the wiper system and wash system in accordance with one or more embodiments. As shown, the wiper system <NUM> includes multiple components in addition to those described with respect to <FIG>. The wiper systems <NUM>, <NUM> include a plurality of sensors. For example, a first sensor is coupled to the output of the motor drive and the ECU, a second sensor is coupled to the output of the brushless motor and the ECU, and a third sensor is coupled to the output of the gearbox/converter and the ECU. It should be understood that additional sensors can be coupled to the ECU and other components of the wiper system to detect the proper operation of the wiper system. These sensors include current sensors, speed sensors, and position sensors.

<FIG> depicts a system architecture similar to that shown in <FIG> having a common ECU <NUM> in accordance with one or more embodiments. The pilot windscreen wiper system and the co-pilot windscreen wiper system can be configured with respective MCUs for controlling the wiper systems.

<FIG> depicts a high-level architecture of the wiper system <NUM> for wiper blade monitoring in the windscreen wiper system. The ECU <NUM> is shown including an RFID module <NUM>, Control Module <NUM>, and Avionics Interface Module <NUM>. The control module <NUM> of the ECU <NUM> includes a configurable usage limit and persistent memory. The blade replacement interval and blade retirement interval can be configured and stored in the persistent memory of the control module <NUM>.

The computing unit of the ECU <NUM> is configured to determine whether the wiper blade has been replaced by comparing the currently read blade information associated with the RFID tag against the previously stored blade information from the persistent memory.

The computing unit interfaces with the avionics interface module <NUM> for reporting the current blade usage status to the cockpit and to a computing device such as but not limited to a ground maintenance computer or server, or other maintenance device such a laptop, PED, smart device, etc. for preventive maintenance.

The RFID module <NUM> of the ECU <NUM> includes an RFID reader that is configured to communicate with the RFID tag of the wiper blade. The RFID reader is configured to energize the passive RFID tags, responsively the RFID tag transmits a unique serial number to the RFID reader. The RFID antenna is used to communicate with the RFID tag of the wiper blade. The RFID reader obtains the blade information from the RFID tags such as the unique serial number that identifies the individual wiper blades.

In one or more embodiments, upon power-up or during initial built-in test (IBIT) process, the computing unit reads the blade information through the RFID reader and stores it in the persistent memory, and the computing unit compares the currently read blade information against the previously stored blade information from the persistent memory.

The Avionics Interface Module <NUM> also includes a communication interface that is configured to communicate over a wireless or wired communication channel. The communication interface is coupled to a wireless transceiver and wireless antenna to communicate over the wireless channel. The communication interface can be coupled to or directly connected to the wired connection such as the avionics bus.

The blade usage ratio (BUR) can be calculated according to the following Equation <NUM>: <MAT> where the current blade usage is based on a duration of operation of the wiper blades or a number/count of sweeps during operation of the wiper blades, and the replacement interval can be configured for a particular type, model, or material used for the blade.

The blade usage status can be determined as follows: <MAT>.

The ECU continuously monitors the wiper blade usage and determines the blade usage status. If the calculated BUR is less than a first threshold1, the wiper blades are healthy and the normal indicator is annunciated. If the BUR is between a first threshold <NUM> and a second threshold2 a warning indicator is annunciated. If the BUR is between a second threshold2 and a third thresholds an error continue alert is annunciated. In this error state operation of the wiper system is allowed to continue. If the BUR exceeds the third thresholds, and error stop alert is annunciated. In this error state, further operation is not recommended and the wiper system should be stopped to replace the wiper blades.

It should be understood that the thresholds can be configured based on different levels of alarms and types of wipers. The thresholds can be stored in the memory and used by the ECU to compare the current status of the wiper blades to the thresholds to determine the corresponding status indicator.

In one or more embodiments, the rubber wear out in the blade that can occur during use causes cuts in the tracks in the passive RFID tag. The computing unit identifies the installation of incompatible blades and/or blade rubber wear out in the wiper system by monitoring the unresponsiveness of the passive RFID tag embedded in the wiper blade.

<FIG> depicts another diagram of a system <NUM> used for monitoring the health of the wiper blades system. As shown, the ECU <NUM> is coupled to the MCU <NUM> which controls the operation of the wipers <NUM>, an LED indicators <NUM> configured to provide a health status of the wiper blades, and a PED <NUM> configured to communicate with the ECU <NUM>. The data collected from the ECU <NUM> can be provided to and displayed on the PED for maintenance personnel.

The PED can be configured to communicate with the ECU over the communication interface or the wireless transceiver shown in <FIG>. The PED can be connected to the ECU using a wired/wireless connection to download the wiper blade health and usage data. In addition, the PED can also receive the generated replacement indicators and reports. The PED provides an interface to alert the maintenance/crew of the detailed health status and replacement advisory of the wiper blade.

As shown, the RFID tags <NUM> are embedded in the wiper blades <NUM> that are attached to the wiper arms on the pilot side and the co-pilot side of the windscreen.

The indication system <NUM> having LED indicators can include a number of light indicators that can be activated by signals from the ECU. This can indicate the current health of the wipers based on the usage history of the wiper system based on the total duty cycle and motor commands processed during operation.

It should be understood that the ECU <NUM> can be configured with additional modules to run in a maintenance mode and perform the computation for the wiper blade usage. In one or more embodiments, in the event, the RFID reader or scanner is unavailable the wiper information (installation date and time, wiper blade identification, etc.) can be manually entered into the system.

<FIG> depicts another view of the system of <FIG> used for health monitoring of the wiper blades system in accordance with one or more embodiments. <FIG> depicts the windscreen portion <NUM> and the cockpit portion <NUM> of the system. The windscreen portion <NUM> includes an RFID tag <NUM> that is embedded in the wiper blade <NUM> and is configured to communicate with an RFID scanner <NUM>. The RFID tag <NUM> contains the wiper blade installation date and time stored. In one or more embodiments, an RFID scanner device is used to collect the data from the RFID tag <NUM>.

The cockpit portion includes the ECU <NUM>, the MCU <NUM>, the LED indicators <NUM>, and the PED <NUM>. The ECU <NUM> is configured to continuously monitor the information and usage history of the blades and stored the information in the storage section <NUM> of the ECU <NUM>. The application section <NUM> of the ECU <NUM> analyzes the data stored and applies arithmetic computations defined in the algorithms to compute the wiper blade usage. The total duty cycle remaining can be calculated as follows according to Equation <NUM>: <MAT> where t is the function of the amount of time spent in a particular mode of operation. The estimated duty cycle is based on the life of the wiper blade.

The ECU <NUM> calculates the total duty cycle remaining and various indicators can be provided upon reaching configurable thresholds and/or levels. For example, the red LED can be illuminated when the wiper blade usage has reached the maximum limit. When the total duty cycle is half the life of the wiper blades a yellow LED can be illuminated and a green LED can be illuminated until the half age is reached. The ECU <NUM> can generate reports and logs for the processed data to indicate the health of the wiper blades.

It should be understood that any number and color of indicators can be used to provide various status levels. In addition, various alarms, alerts, feedback, etc. can also be coupled with the indicators to provide the status levels.

<FIG> depicts an illustration of the storage section <NUM> and the application section <NUM> of the ECU <NUM> in accordance with one or more embodiments. The storage section <NUM> of the ECU <NUM> stores the data in the storage <NUM>. In one or more embodiments, the storage <NUM> can include a non-volatile memory (NVM). The storage <NUM> is configured to store the duration of time or a number of sweeps in which the wiper blades are operated in the various modes. For example, duration t1 is recorded in the storage <NUM> when operating the wiper system in the low-speed mode, duration t2 and t3 are recorded when operating in the medium-speed mode and high-speed mode, respectively. As shown, when operating in the low-speed mode the duty cycle for operating the windscreen wipers is lower than that of the medium-speed and high-speed modes.

The application section <NUM> processes the logs and generates various reports such as the blade usage details <NUM>, remaining hours details <NUM>, blade replacement history <NUM>. It should be understood the application section <NUM> of the ECU can be configured to processing additional data and/or generate additional reports and is not limited by that provided in <FIG>.

<FIG> depicts a method <NUM> for providing monitoring of the wiper system in accordance with one or more embodiments. The method <NUM> begins at block <NUM> and proceeds to block <NUM> which provides for reading an RFID tag embedded in a wiper blade using a reader. The reader energizes the RFID tag and obtains the blade information transmitted from the RFID tag. The read blade information can be stored in the memory of the ECU.

Block <NUM> determines when the wiper blade was put into service based on a state corresponding to the read RFID tag. In one or more embodiments, an ECU compares the read RFID tag to the stored wiper blade information. If the blade information does not result in a match, it is determined that the blade has been replaced and the usage count/blade usage ratio for the blade is reset. If there is a match, it is determined that the blades have not been replaced and the usage count/blade usage ratio continues to be added to the current count. In addition, in the event the reader is unable to obtain a successful read from the RFID tag, it can be determined that the RFID tag is damaged due to overuse or some other fault that requires further inspection exists.

Block <NUM> determines a blade usage based on time elapsed since the wiper blade was placed into service. Block <NUM> determines a blade usage ration for the wiper blade based on time elapsed and the blade replacement, and block <NUM> provides an indication of a status of the wiper blade based at least in part on the blade usage ratio.

In one or more embodiments, the blade replacement interval and blade retirement interval can be stored in the persistent memory. The replacement interval and blade retirement interval are configurable parameter and can be based on the specific windscreen wiper that is being used. The method <NUM> can end at block <NUM>. In other embodiments, the method <NUM> can continue to monitor the wiper blade as provided with reference to the method <NUM> of <FIG>.

The method <NUM> for monitoring the health of a windscreen wiper system in accordance with one or more embodiments. The method <NUM> begins at block <NUM> and proceeds to block <NUM> which monitors, via an ECU, an operation of the wipers of the wiper system. The ECU is configured to monitor the duty cycle and motor commands from the MCU that are used to drive the wipers of the wiper system.

Block <NUM> calculates a total duty cycle of operation for the wiper blades, and Block <NUM> compares the total duty cycle to a duty cycle threshold. Block <NUM> provides an indication based at least in part on the comparison of the total duty cycle to the duty cycle threshold for the wiper blade. The method <NUM> ends at <NUM>. It should be understood that the method <NUM> can continuously monitor the wiper blades in accordance with the method.

Referring now to <FIG>, an aircraft <NUM> is shown that can implement the systems described herein. It should be understood the wiper system and wash system can be implemented on other types of vehicles not limited to rotorcrafts, trains, boats, and other vehicles.

The technical effects and benefits include automatic monitoring of the wiper blade usage of the wiper system in a variety of modes which can aid in the accurate planning of the maintenance of the wiper system.

Claim 1:
A method for monitoring a wiper system, the method comprising:
reading (<NUM>) a radio frequency identification (RFID) tag embedded in a wiper blade using a reader;
determining (<NUM>) when the wiper blade was put into service based on data stored corresponding to the read RFID tag;
determining (<NUM>) blade usage based on time elapsed since the wiper blade was placed into service;
determining (<NUM>) a blade usage ratio for the wiper blade based on time elapsed and a blade replacement interval,
providing (<NUM>) an indication of a status of the wiper blade based at least in part on the blade usage ratio;
monitoring, by an electronic control unit, an operation of the wiper blade of the wiper system;
calculating a total duty cycle for operating the wiper blade;
comparing the total duty cycle to a duty cycle threshold;
providing an indication of a health status of the wiper blade based at least in part on the comparison of the total duty cycle to the duty cycle threshold
operating the wiper blade system in at least a low-speed mode, a medium-speed mode, and a high-speed mode;
calculating a duty cycle corresponding to each mode of operating the wiper blade system, wherein calculating the total duty cycle comprises function of duration of time the wiper blade is operated in each mode, and
connecting the ECU to at least one of an LED indicator system or external device (PED) to display the health status of the wiper blade based on the total duty cycle;
wherein, when operating in the low-speed mode, the duty cycle for operating the windscreen wipers is lower than that of the medium-speed and high-speed modes.