This application is a National Stage of International Application No. PCT/US2006/020682, filed May 30, 2006. This application claims priority to U.S. Patent Application No. 60/685,917 filed on May 31, 2005. The disclosures of the above applications are incorporated herein by reference.
The present invention relates to a control strategy for self calibrating actuators under specific conditions, wherein the control strategy further provides a partial calibration feature that will maintain adequate actuator performance.
It is common practice in the automotive industry to use electric actuators to control various vehicular functions. These control actuators are often faced with operating in harsh environments that are subject to change. As a result the operation of these actuators can become misaligned or sometimes blocked. Thus periodic calibration or confirmation of the actuator function is often necessary to ensure that the actuator has a proper range of operation. An example of a type of system where calibration or confirmation is desirable is in a turbocharger. The actuator in a turbocharger is used to control the turbocharger unit and the boost pressure that the unit provides to the engine. If the actuator becomes misaligned then the valves in the turbocharger may not open properly and cause an incorrect pressure differential across the turbine. The misadjustment or misalignment of the valves can result in poor engine performance, failure to meet emissions legislation, or damage to the turbocharger and related vehicle components.
It is desirable to configure or program the actuator to calibrate itself when predetermined time periods or conditions exist. Doing so will prevent an intrusive event that may affect the engine performance, vehicle emissions, or potential system damage.
The present invention is related to a method of controlling a device having a calibration process. The calibration process has a partial calibration routine and a calibration routine. A detector within the control system is capable of receiving one or more input signals and determining whether a partial calibration or calibration should occur. The first step in the process involves starting the control method where the detector receives input signals or generates its own data within the detector. Next the detector determines if a calibration is required based on the values. The detector also determines whether a partial calibration routine or a calibration routine will take place based upon the value of the input signals received. A partial calibration routine will be performed if the input signals to the detector do not favor doing more than a partial calibration. If a partial calibration routine occurs, then the device is commanded to move to a first function or limitation of its operating range so that the device learns the characteristic of the limitation. Next the device operates using the learned characteristic and a previously stored value of a second characteristic representing the second limitation or function of the operating range of the device. If it is determined that a calibration routine will take place then the device will learn the first characteristic as described above, and a second characteristic located at a second function or limitation of the operating range of the device. After a calibration routine the device will then operate using the learned values of the first characteristic and second characteristic obtained during the calibration routine.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
Referring to
After the step 12 the device will proceed to a step 14 and determine if the calibration or verification of the device's parameters is required. This determination is based on various inputs, shown in
Once it has been determined at step 14 that a calibration or verification will take place the device will advance to a step 16. At step 16 the device will determine which type of calibration or verification to perform. The device may command a partial calibration, which is just one portion of a calibration routine, by learning or verifying the value of a first function at a step 18. At a step 20 the device will operate using the value of the first function and a previously stored value for a second function. The previously stored value can be a pre-programmed value, an end of line value, or a value obtained from the last calibration routine. The partial calibration will then be completed at a finish step 22 where the device will continue to operate using the learned position obtained at step 18 and the previously stored value for function 2 supplied at step 20 for operation of the device.
If at step 16 the device determines that the calibration routine is needed then the device will learn the position of a first function at step 24. The device will learn the position of a second function at a step 26. At a step 28 the device will verify the operation of the operating range of the device by moving between the learned position of the first function and the learned position of the second function. The device will then finish the calibration routine at a step 30 and operate using the learned positions obtained at steps 24 and 26.
The control method described in
The ACU 116 receives the information from the ECU 111. The ACU 116 then determines at a step 120 whether or not conditions allow for the actuator to perform a partial calibration routine. If at step 120 it is determined that a calibration routine is not possible due to the engine conditions or other factors, then at step 122 the ACU 116 performs a partial calibration with the actuator 122. A partial calibration is where the ACU 116 commands the actuator to drive to a second function. The ACU 116 then records the value of the second function, replacing learned values from previous partial calibrations or preprogrammed values. At step 124, the actuator then operates using previously stored data regarding a first function and the information acquired during the partial calibration 122. At step 120, the ACU 116 will continue to monitor and determine when conditions will allow for a calibration routine step 126 to be performed. For example, when the engine is sitting at idle or is cruising at ideal cruising speeds, the ACU 116 performs the step 126 of calibration with the actuator. During step 126, a calibration routine of the actuator is driven to all the functions within the range of the actuator. The ACU 116 then records the values of all the actuator's functions, replacing the learned values from previous calibration routines. Then at step 128 the ACU 116 operates using the data acquired during the calibration.
In the preferred embodiment the ECU 111 is configured to transmit information 114 to the ACU 116, and the ACU 116 is configured to receive information 118 from the ECU 111. The control strategy 110 can be implemented in applications where there is a single controller, such as a configuration where the ECU directly controls the actuated device. It is also within the scope of the present invention for the ACU 116 to be integrated into the device or for the ACU 116 to be a separate unit. Additionally, it is possible to implement the control strategy 110 of the present invention into a situation where there are two or more controllers. Such an embodiment would allow for the coordination for multiple controller units making or allowing the control strategy to operate based on multiple variables. For example, multiple controllers could input signals to the ECU so that the ECU could command the actuator to perform various learn sequences based upon signal values from various engine system components. One example of such an alternate embodiment would be where the ACU receives a signal from the ECU that is representative of engine conditions, while another variable inputted to the ECU could be a value inputted from a controller that monitors electrical consumption of the vehicle's cabin compartment.
It is possible for the conditions to direct the ACU 116 to perform step 126 when electrical disturbances in the vehicle may affect the performance of an actuator, which would then require the actuator to perform a calibration process. Electrical disturbances include high voltage, low voltage, or intermittent voltage; where an intermittent voltage could be caused by manufacturing defects, mechanical stress, or corrosion. However, before the ACU 116 performs a calibration with the actuator it must be determined if the ACU 116 has received information from the ECU 111. If the ACU 116 has received information from the ECU 111 then the ACU 116 can determine if conditions allow for a calibration at step 120. The reason the ACU 116 must receive information from the ECU 118 before the ACU 116 can determine if conditions allow for a calibration routine is to ensure that the ACU 116 does not perform a calibration routine with the actuator during certain engine operating conditions. Therefore, after the steps 122, 123 of performing a partial calibration routine are complete, the ACU 116 disregards other factors that direct the ACU 116 to command the actuator to perform the step 120 of a second self calibration process until the ECU transmits a second input signal to the ACU 116, to allow the ACU 116 to command the actuator to run the second self calibration process. Under certain engine operating conditions a calibration process is performed it can cause poor engine performance, failure to meet emissions legislation, or damage to vehicle components. Also prior to engine start-up or at engine shut down the signals transmitted by the ECU can cause the ACU to command a calibration process. A specific example includes calibration or verification that must occur prior to an engine reaching a specific RPM during starting.
If the ACU 116 has not received information from the ECU, but the conditions have directed the ACU 116 to perform a calibration; the ACU 116 will perform a partial calibration with the actuator at step 122. A partial calibration will not cause undesirable effects while being performed. After the partial calibration has been performed the actuator operates using previously stored data and the information acquired during the partial calibration at step 124. The control strategy 110 must then reset in order to determine if the conditions allow for a calibration at step 120.
The devices that the present control strategies 10, 110 can be used with are devices or actuators such as, but not limited to vehicle engine actuators including turbochargers, exhaust gas recirculation valves, throttle valves, shift actuators, transfer case shift mechanisms, clutches and transmission shift mechanisms, variable cam timing mechanisms, tuning actuators, fuel injectors, etc. The control strategies 10, 110 of the present invention are used to learn or calibrate the functions of these devices and other devices having similar functions. Functions include but is not limited to mechanical stops, current or voltage fluctuation, air flow capacity, torque range angular movement, fuel metering, fuel quantity, force, linear travel, rotary movement, etc.
The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/US2006/020682 | 5/30/2006 | WO | 00 | 11/28/2007 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2006/130534 | 12/7/2006 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
4707789 | Downs et al. | Nov 1987 | A |
5265576 | McMahon et al. | Nov 1993 | A |
5403250 | Juergens | Apr 1995 | A |
5526280 | Consadori et al. | Jun 1996 | A |
5574211 | Shimada et al. | Nov 1996 | A |
5760289 | Skottegard | Jun 1998 | A |
6128902 | Kolmanovsky et al. | Oct 2000 | A |
6298255 | Cordero et al. | Oct 2001 | B1 |
6529815 | Hawkins et al. | Mar 2003 | B2 |
6536261 | Weldon et al. | Mar 2003 | B1 |
6965826 | Andres et al. | Nov 2005 | B2 |
7162356 | Fuwa et al. | Jan 2007 | B2 |
7374513 | Whitton | May 2008 | B2 |
7467033 | Miller et al. | Dec 2008 | B2 |
7707821 | Legare | May 2010 | B1 |
20020171819 | Cheung | Nov 2002 | A1 |
20030229430 | Beek | Dec 2003 | A1 |
20040218199 | Regimbal | Nov 2004 | A1 |
20040221899 | Parsons et al. | Nov 2004 | A1 |
20050001188 | Everingham et al. | Jan 2005 | A1 |
20050021217 | Bhargava et al. | Jan 2005 | A1 |
20050107212 | Soliman et al. | May 2005 | A1 |
20050185227 | Thompson | Aug 2005 | A1 |
Number | Date | Country |
---|---|---|
0512690 | Nov 1992 | EP |
2788143 | Jul 2000 | FR |
WO 2004022949 | Mar 2004 | WO |
Number | Date | Country | |
---|---|---|---|
20090267557 A1 | Oct 2009 | US |
Number | Date | Country | |
---|---|---|---|
60685917 | May 2005 | US |