DIRECT DRIVE CABLE-OPERATED ACTUATION SYSTEM FOR CLOSURE PANEL

An actuation system and method of operation for moving a closure panel in one of a normal drive state and a back drive state are provided. The actuation system includes a mechanical coupling for moving the closure panel. A motor with a shaft is directly and operably connected to the mechanical coupling to directly move the mechanical coupling. A sensor detects movement of the closure panel and couples to a controller connected to the motor. The controller moves the closure panel with the motor based on a detected motor movement command in the normal drive mode. The controller also detects movement of the closure panel using the at least one sensor and selectively brakes the movement of the closure panel based on the movement detected in the back drive state.

FIELD

The present disclosure relates generally to motor vehicle closure panels, and more particularly to power-operated actuation systems therefor.

BACKGROUND

In many motor vehicle door assemblies, an outer sheet metal door panel and an inner sheet metal door panel are connected together to define an internal door cavity therebetween. In some motor vehicle door assemblies, such as those including power-operated windows, an equipment module or sub-assembly, commonly referred to as a carrier module, or simply carrier, is mounted to the inner door panel within the internal door cavity. The carrier typically functions to support various door hardware components, such as a window regulator rail1shown inFIGS. 1A and 1B, for example, configured to support lifter plate2for selectively slidable movement therealong, as well as an actuator system3configured to drive the lifter plate2along the window regulator rail1. The lifter plate2is fixed to a window (not shown) to cause the window to slide up and down therewith along the direction of guide channels within the window regulator rail1in response to powered actuation of the actuator system3.

The actuator system3typically includes a regulator motor4operably connected to a cable drum5via a gearbox assembly6(inFIG. 1B, a drum cover of the cable drum5is hidden for clarity). Motor4typically has an output shaft extending to a worm gear, with the worm gear being configured in meshed engagement with a drive gear of the gearbox assembly6. The gearbox assembly6typically includes a planetary gearset with an output gear member configured in meshed engagement with an input gear of the cable drum5. Unfortunately, the aforementioned actuator system3experiences inherent inefficiencies due to the gearing losses resulting from friction and slop (play) between the several intermeshed gears. As a result of the inherent operational inefficiencies, components, such as the motor4, are often increased in power, size and weight, which inherently increases cost and decreases fuel efficiency.

In addition to motor vehicle door assemblies including power-operated windows, other motor vehicle door assemblies, such as power-operated sliding doors, can include similar types of actuator systems as discussed above for actuator system3, in addition to clutches, to facilitate sliding movement of the power-operated sliding doors between closed and open positions. Accordingly, during powered movement of the sliding door, similar losses are typically experienced within the gearbox assembly of the actuator system, as well as in the associated clutches.

In view of the above, there is a need to provide actuation systems for motor vehicles that are efficient in operation, while at the same time being compact, robust, durable, lightweight and economical in manufacture, assembly, and in use.

SUMMARY

This section provides a general summary of the disclosure and is not intended to be a comprehensive listing of all features, advantages, aspects and objectives associated with the inventive concepts described and illustrated in the detailed description provided herein.

It is an object of the present disclosure to provide actuation systems for a closure panel of a vehicle that address at least some of those issues discussed above with known actuation systems.

In accordance with the above object, it is an aspect of the present disclosure to provide actuation systems that are efficient in operation, while at the same time being compact, robust, durable, lightweight and economical in manufacture, assembly, and in use.

In accordance with another aspect of the disclosure, the present disclosure is directed to an actuation system for moving a closure panel of a vehicle in one of a normal drive state and a back drive state. The actuation system includes a mechanical coupling connected to the closure panel for moving the closure panel in between an open position and a closed position. The actuation system also includes a motor having a shaft directly and operably connected to the mechanical coupling and configured to directly move the mechanical coupling. The actuation system additionally includes at least one sensor for detecting movement of the closure panel. The actuation system additionally includes a controller electrically coupled to the motor and to the at least one sensor and configured to detect a motor movement command in the normal drive state. The controller is also configured to directly move the closure panel with the motor based on the motor movement command detected in the normal drive state and detect movement of the closure panel using the at least one sensor in one of the normal drive state and the back drive state. The controller controls operation of the motor based on the movement detected and the motor movement command detected in one of the normal drive state and the back drive state. The controller also selectively brakes the movement of the closure panel in between the closed position and the open position based on the movement detected in the back drive state.

In accordance with yet another aspect of the disclosure, the present disclosure is directed to a method of operating an actuation system for moving a closure panel of a vehicle in one of a normal drive state and a back drive state. The method includes the step of detecting a motor movement command using a controller in the normal drive state. Next, directly moving the closure panel in between an open position and a closed position with a motor having a shaft directly and operably connected to a mechanical coupling connected to the closure panel based on the motor movement command detected in the normal drive state. The method then includes the step of detecting movement of the closure panel using at least one sensor coupled to the motor and the controller in one of the normal drive mode and the back drive state. The method proceeds by controlling operation of the motor using the controller based on the movement detected and the motor movement command detected in one of the normal drive mode and the back drive state. The method also includes the step of selectively braking the movement of the closure panel in between the closed position and the open position based on the movement detected using the controller in the back drive state.

In accordance with yet another aspect, there is provided an actuation system for moving a closure panel of a vehicle, including a mechanical coupling connected to the closure panel for moving the closure panel in between an open position and a closed position, and a motor having a shaft directly and operably connected to the mechanical coupling and configured to directly move the mechanical coupling.

In a related aspect, a gear reduction mechanism is not interconnected between the shaft and the mechanical coupling.

In another related aspect, a clutch mechanism is not interconnected between the shaft and the mechanical coupling.

In another related aspect, the motor is a brushless motor.

In another related aspect, the shaft is interconnected to the mechanical coupling by a transmission.

In another related aspect, the transmission is a backdrivable transmission.

In another related aspect, the actuation system includes a braking system coupled to at least one of the mechanical coupling and the transmission and the motor.

In another related aspect, the braking system comprises a braking assembly configured for selectively braking the movement of the closure panel, the at least one of the mechanical coupling and the transmission and the motor.

In another related aspect, the braking system includes at least one sensor for detecting movement of at least one of the closure panel, the mechanical coupling, the transmission, and the motor; and a controller electrically coupled to the motor and to the at least one sensor and configured to detect movement of the at least one of the closure panel, the mechanical coupling, the transmission, and the motor using the at least one sensor and to selectively brake the movement of the closure panel in between the closed position and the open position based on the detected movement.

In another related aspect, the controller is configured control the motor to oppose the detected movement of the at least one of the closure panel, the mechanical coupling, the transmission, and the motor.

In another related aspect, the motor is a brushless motor and the controller is configured to control the motor using a field oriented control methodology comprising supplying a flux linkage voltage command and a torque voltage command to the motor.

In accordance with another related aspect, there is provided method of constructing an actuation system for moving a closure panel of a vehicle including the steps of providing a mechanical coupling connected to the closure panel for moving the closure panel in between an open position and a closed position; and providing a motor having a shaft directly and operably connected to the mechanical coupling and configured to directly move the mechanical coupling.

Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are only intended to illustrate certain non-limiting embodiments which are not intended to limit the scope of the present disclosure.

DETAILED DESCRIPTION

The expression “closure panel” will be used, in the following description and the accompanying claims, to generally indicate any element movable between an open position and a closed position, respectively opening and closing an access to an inner compartment of a motor vehicle, therefore including, but not limited to boot, doors, liftgates, sliding doors, rear hatches, bonnet lid or other closed compartments, windows, sunroofs, in addition to the side doors of a motor vehicle.

In general, the present disclosure relates to an actuation system of the type well-suited for use in many applications. The actuation system and associated methods of operation of this disclosure will be described in conjunction with one or more example embodiments. However, the specific example embodiments disclosed are merely provided to describe the inventive concepts, features, advantages and objectives with sufficient clarity to permit those skilled in this art to understand and practice the disclosure. Specifically, the example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

Now referring toFIG. 2of the drawings, an example of a motor vehicle10is shown having a vehicle body12, a hinged front door14and a sliding rear door16. Front door14is equipped with a window18which is moveable between closed and open positions via a power-operated window lift system. Similarly, rear door16is equipped with a window20which is moveable between closed and open positions via a power-operated window lift system. While the present disclosure will hereinafter be specifically directed to describing the window lift system associated with a door16, those skilled in the art will recognize and appreciate that similar arrangements to that described herein can be adapted for use with front door14and/or a window22associated with a hinged liftgate24, as well as any other type of closure panel, such as sliding doors, sunroofs and the like, and as well as other vehicle power actuators, such as for power release, power lock in vehicle door latches, as well as for cinching actuators, and the like.

FIG. 3shows a window regulator26of an actuation system27for moving the window20in vehicle door16, in accordance with aspects of the disclosure. The window regulator26includes a motor28,28′, a drum30, a set of three drive cables32, shown individually at32a,32band32c, two rails34shown individually at34aand34b, two lifter plates36, shown individually at36aand36b.

The rails34may be mounted in any suitable way to the vehicle door16. For example the rails34may be mounted to a carrier panel38that is inside the vehicle door16. The lifter plates36hold the window20and are slidably mounted on the rails34. The cable32aconnects between the drum30around a pulley39at an end of rail34aand the first lifter plate36a. The cable32bconnects between the drum30around a pulley at an end of rail34band the second lifter plate36b. The cable32cis mounted between the two lifter plates36and wraps around pulleys39at ends of both rails34. The lifter plates36are driven upwardly and downwardly via the cables32, which are themselves driven by rotation of the drum30. The drum30is rotated in a first direction or a second opposite direction by the motor28,28′ depending on whether the occupant of the vehicle10wishes the window18to be raised or lowered. The motor28,28′ may be a bidirectional electric motor.

According to another aspect, best shown inFIG. 4, the actuation system27may utilize or comprise a single rail window regulator40. Regulator40includes a rail42along at least a portion of the length of which a lifter plate44can slide. A guide, in the illustrated embodiment a pulley46, is mounted adjacent one end of rail42. At the end of rail42opposite pulley46, a drive means48is located, drive means48comprising motor28,28′ (e.g., direct current motor) and a driven drum50which can be turned in a clockwise or counter clockwise direction by operation of motor28,28′ in a respective direction.

Driven drum50can be connected to motor28,28′ by any suitable means, such as a gear train and/or a clutch mechanism, as will be apparent to those of skill in the art and a housing52encloses the gear train and/or clutch mechanism and includes three bores in or through which mounting bolts54,56and58can be received. Bolt58extends through rail42to pivotally connect drive means48to rail42. Bolt56can be employed to assist in mounting regulator40within the vehicle10and bolt54can engage a slot in the end of rail42, to prevent further pivotal movement of drive means48with respect to rail42once regulator40is assembled.

A flexible drive member62extends from a first attachment point64on lift plate44down to driven drum50about which it is wrapped and then up to and around pulley46and then down to a second attachment point66on lifter plate44. As shown, flexible drive member62is a wire cable. Configurations of driven drum50and pulley46which are suitable for other flexible drive member62, such as belts, will be apparent to those of skill in the art. Further, rather than a pulley46, the guide for flexible drive member62can be any suitable device about which flexible drive member62can move. Suitable guides for wire cables62can include a Delrin™ disc with grooves in its perimeter edge, the wire cable62sliding through the groove around the perimeter of the disc when the wire cable62is moved.

As best shown inFIGS. 5A-5B, the actuation system27for moving a closure panel (e.g., window20) of the vehicle10in one of a normal drive state and a back drive state is provided according to other aspects of the disclosure. The actuation system27includes a mechanical coupling70connected to the closure panel (e.g., window20) for moving the closure panel20in between an open position and a closed position. Other types of mechanical couplings70may be provided such as a center hinge or sliding door bracket as described in U.S. Pat. No. 7,770,961 entitled “Compact cable drive power sliding door mechanism”, the entire contents of which are incorporated herein by reference.

The actuation system27also includes the motor28,28′ having a shaft72directly and operably connected to the mechanical coupling70and configured to directly move the mechanical coupling70. So, the mechanical coupling70can be the drum30,50directly connected to the shaft72(the drum30,50is shown with a drum cover hidden for clarity inFIG. 5B). In addition, the actuation system27includes a controller74electrically coupled to the motor28,28′ and to at least one sensor114a,114b,114c(FIG. 11). The controller74is configured to detect a motor movement command in the normal drive state (e.g. from a switch109or a signal from a body control module/BCM137inFIGS. 9A-9B) and directly move the closure panel20with the motor28,28′ based on the motor movement command detected in the normal state. The controller74also detects movement of the closure panel20using the at least one sensor114a,114b,114cin one of the normal drive mode and the back drive state. The controller74additionally controls operation of the motor28,28′ based on the movement detected and the motor movement command detected in one of the normal drive state and the back drive state. The controller74is also configured to selectively brake the movement of the closure panel20in between the closed position and the open position based on the movement detected using the controller74in the back drive state. The controller74also detects movement of the closure panel20using other types of sensor configurations, such as for detecting directly the movement of the window20, or movement of any component in the transmission between the window20and the motor28,28′.

As best shown in the block diagrams ofFIG. 6A-6C, a plurality configurations of the controller74, motor28,28′, and mechanical coupling70of the actuation system27may be utilized to directly drive the closure panel20. Referring toFIG. 6A, the closure panel is a window20of the door16. The motor28,28′ is a brushed electrical motor28and the mechanical coupling70includes a direct drive or direct mechanical connection between the shaft72of the motor28and a lifter plate36,44of the window regulator40. Thus, because no gear train is utilized, efficiency of the actuation system27can be improved; however, it is still possible to back drive the actuation system27. In the case of the window20, for example, it may be undesirable to allow back drive, as the security of a closed window20could be compromised by window20being forced back or back driven into the door16or body of the vehicle10. The actuation system27ofFIG. 6Bis similar to that shown inFIG. 6A; yet, instead of a brushed electric motor28, the actuation system27shown utilizes a brushless direct current motor28′. Thus, the back drive can be countered or corrected by control of the brushless direct current electric motor28′. In,FIG. 6C, another exemplary actuation system27is shown. Again, the closure panel is the window20of the door16. The mechanical coupling70includes a rail34,42for coupling to the door16and a lifter plate36,44is attached to the window20and slidably mounted on the rail34,42. A cable32,62attaches to the lifter plate36,44. A drum30,50is directly coupled to the shaft72of the motor28,28′ with the cable32,62looped about the drum30,50for moving the cable32,62and the lifter plate36,44along the rail in response to rotation of the shaft72of the motor28,28′. Thus, as inFIGS. 6A and 6B, there is no gear train, as the drum30,50is directly coupled to the shaft72of the motor28,28′. Again, inFIG. 6C, the motor28,28′ is a brushless direct current electric motor28′. It should be understood that although one is not shown inFIG. 6C, a planetary gear train may be utilized as part of the mechanical coupling70.

Now referring toFIGS. 7A-7D, additional configurations of the controller74, motor28,28′, and mechanical coupling70of the actuation system27are provided to additionally allow for braking or resistance to movement of the mechanical coupling70, motor28,28′, and/or closure panel20. Referring toFIG. 7A, the closure panel is the window20of the door16and the mechanical coupling70includes a rail for coupling to the door16, a cable32,62directly driven by the shaft72of the motor28,28′, and a lifter plate36,44. The lifter plate36,44is attached to the window20and slidably mounted on the rail and configured to lock the lifter plate36,44at any position along the rail when the motor28,28′ is not operated and the cable32,62is not tensioned by the motor28,28′. The lifter plate36,44also enables motion of the lifter plate36,44when the motor28,28′ is operated and the cable32,62is tensioned by the motor28,28′. In other words, the lifter plate36,44inFIG. 7Ais a locking lifter plate such as in U.S. Pat. No. 7,975,434, incorporated herein by reference. Consequently, back drive is prevented by the locking of the lifter plate36,44.

InFIG. 7B, the motor28,28′ is a brushless direct current electric motor28′ and the mechanical coupling70includes a direct mechanical connection between the shaft72of the motor28,28′ and the lifter plate36,44of the window20. However, as shown, the actuation system27can additionally include a clutch or electromechanical brake assembly76(FIGS. 8, 9A, and 9B) coupled to at least one of the mechanical coupling70and the motor28,28′ (both couplings are shown). The electromechanical brake assembly76is electrically coupled to and controlled by the controller74to selectively move between an engaged status and a disengaged status. The electromechanical brake assembly76is, for example, set to be in the engaged status by default in case of a power loss and the brake is removed (i.e., moved to the disengaged status) only when the motor28′ is driven. In the engaged status, rotation of the shaft72is hindered for braking movement of the mechanical coupling70and the closure panel20between the closed position and the open position in the back drive state. In contrast, in the disengaged status, the shaft72is permitted to rotate and allow movement of the mechanical coupling70and the closure panel20in the normal drive state. So, to prevent back drive, locking or braking is achieved using the electromechanical brake assembly76.

FIG. 7Cdoes not include an electromechanical brake assembly76like inFIG. 7B; nevertheless, locking or braking is achieved by applying power to the motor28,28′ to stop rotation of the shaft72of the motor28,28′ and as a result, stop motion of the mechanical coupling70and closure panel20. Specifically, the motor28,28′ is a brushless direct current electric motor28′ and the mechanical coupling70includes a direct mechanical connection between the shaft72of the motor28′ and the lifter plate36,44of the window20. Thus, the brushless electric motor28′ is capable of braking control (i.e., opposing the closure panel or window20from being back driven), one example of a braking system, and specifically one example of an electronic braking system.

FIG. 7Dillustrates a configuration of the actuation system27in which the mechanical coupling70includes a rail34,42for coupling to the door16and a lifter plate36,44attached to the window20and slidably mounted on the rail. A cable32,62attaches to the lifter plate36,44. The mechanical coupling70also includes a transmission, for example gear train77being back drivable and having a gear train input driven by the shaft72of the motor28,28′ and a gear train output. A drum30,50is coupled to the gear train output with the cable32,62looped thereabout for moving the cable32,62and the lifter plate36,44along the rail34,42in response to rotation of the shaft72of the motor28,28′ as modified by the gear train77. The gear train77can for example be a gear train 77 such as in U.S. Pat. No. 9,234,377, herein incorporated by reference. Specifically, the gear train77can include a worm gear78attached to the shaft72of the motor28,28′ at the gear train input and a spur gear79attaches to a gear shaft80comprising the gear train output and having a plurality of outer peripheral teeth81in meshed engagement with the worm gear78. Such a gear train or transmission as a gear reduction mechanism may have gear reduction properties whereby the speed of the motor is reduced at the output of the transmission for providing speed reduction/torque multiplication. Rotation of the worm gear78by the motor28,28′ causes rotation of the spur gear79in the normal drive state and rotation of the spur gear79causes rotation of the worm gear78in the back drive state. According to an aspect, the worm gear78is formed of brass and the spur gear79is formed of plastic to achieve a coefficient friction sufficient to allow back driving in which rotation of the spur gear79causes rotation of the worm gear78. According to another aspect, a gear ratio between the worm gear78and the spur gear79is at least 50:1 (e.g., 57:1) to allow the worm gear78to be back driven by the spur gear79in the back drive state illustrative as one type of a backdriveable transmission. Nevertheless, it should be appreciated that other gear trains (e.g., other high efficiency, low gear ratio backdriveable gear trains) may be utilized in addition to or instead.

As best shown inFIGS. 8, 9A, and 9B, the electromechanical brake assembly76, another example of a braking system and specifically an example of a mechanical braking system, includes a coil assembly82operably connected to the controller74for receiving electrical current. In more detail, the electromechanical brake assembly76remains in the engaged status when the coil assembly82is de-energized by the absence of the electrical current and remains in the disengaged status when the coil assembly82is energized by the electrical current. The electromechanical brake assembly76also includes a first friction plate83fixed for conjoint rotation with the shaft72and a second friction plate84. The first and second friction plates83,84are biased into frictional engagement with one another when the coil assembly82is de-energized. In more detail, a spring member85biases the first and second friction plates83,84into frictional engagement with one another when the coil assembly82is de-energized. When the coil assembly82is energized, the first and second friction plates83,84are moved out of frictional engagement with one another by a magnetic force from the coil assembly82. The shaft72of the motor28,28′ extends axially through the motor28,28′ from a first end86attached to the mechanical coupling70(e.g., drum30,50) to a second end87attached to the first friction plate83of the electromechanical brake assembly76.

As best shown in the exploded view ofFIG. 8, the electromechanical brake assembly76includes a brake housing88having an end mount face89and an annular outer wall90, shown as being generally cylindrical and bounding an inner cavity91sized for substantial receipt of various components of the brake assembly76. To facilitate fixing the brake assembly76in position, the end mount face89is shown having a plurality of through openings92for receipt of fasteners therethrough, wherein the fasteners can be provided as threaded fasteners for threaded receipt into an end of the motor28,28′ (FIGS. 9A-9B), by way of example and without limitation. The brake assembly76further includes a spacer93, also referred to as a shim. The electromagnetic coil assembly82has a conductive electrical wire94spirally wound about a bobbin95and configured in operable electrical communication with a source of electric current; and a coil housing96.

The coil housing96has an annular outer wall97and a central, tubular post98extending along the axis A from an end wall99to a free end, with a toroid-shaped cavity100extending between the wall97and post98for receipt of the coil assembly82therein. The bobbin95of the coil assembly82has a through opening or passage101sized for close receipt about an outer surface of the post98and is sized for close receipt within the cavity100of the coil housing96.

As best shown inFIGS. 9A and 9B, there is a direct mechanical coupling between the shaft72and the drum30,50. The spacer93is disposed in a cavity or pocket102bounded by the wall of the tubular post98, such that the spacer93is brought into abutment with the end wall99. The spring member85is disposed in the pocket102against the spacer93, wherein the spring member85has a length sufficient to extend axially along the axis A (FIG. 8) outwardly from and beyond a free end103of the tubular post98while in an unbiased, axially decompressed state. It should be recognized that the spacer93can be provided with the desired axial thickness to adjust the force of the spring member85applied to the second friction plate83by adjusting how far the spring member85extends axially beyond the free end103of the post98, in addition to adjusting the spring constant of the spring member85. With the brake housing88fixed to the motor28,28′, the first friction plate83is operably connected for fixed attached to the second end87of the shaft72of the motor28,28′ for conjoint rotation therewith, such as via a press fit, bonded and/or fixed thereto via a mechanical fastener, by way of example and without limitation, while the first end86of the shaft72is operably fixedly coupled with the drum30,50. The second friction plate84is disposed in the brake housing88between the first friction plate73and the spring member85, such that the spring member85engages the second friction plate84and forcibly biases the second friction plate84into contact with the first friction plate83upon completing assembly, and while in the “on position” or “engaged status.” The second friction plate84is not provided for rotation movement about the axis A, but rather, for sliding movement along the axis A during movement between the “engaged” and “disengaged” statuses. To facilitate smooth sliding movement, the second friction plate84is shown as having a plurality of radially outwardly extending tabs or ears104for close sliding engagement with an inner surface of the brake housing outer wall90. To facilitate establishing high frictional engagement between the first and second friction plates83,84while in the “engaged status,” the second friction plate84is shown as having a high coefficient friction material formed in shaped of an annular band105fixed within an annular groove107in an end face of the second friction plate84. Accordingly, the annular band105extends axially outwardly from the end face of the second friction plate84for frictional engagement with an end face of the first friction plate83while in the “engaged status.” It should be recognized that the band105could be fixed to the first friction plate83, or to both the first and second friction plates83,84, as desired to obtain the degree of frictional engagement therebetween. It should also be recognized that any suitable high friction coefficient material can be used for the band105, and further, that the end faces of the first friction plate83and/or the second friction plate84can be surface treated or otherwise roughened, as desired, to facilitate providing a high degree of friction therebetween for holding the first friction plate83and preventing the first friction plate83from rotating while in the “engaged status.” One skilled in the art of braking surfaces will readily appreciate numerous mechanisms for obtaining a brake condition between the first and second friction plates83,84upon viewing the disclosure herein, with those mechanisms being contemplated and incorporated herein by reference.

Still referring toFIGS. 9-10, an electrical lead106extends from the controller74into electrical communication with the electromechanical brake assembly76, and in particular, with the coil assembly82of the electromechanical brake assembly76. When the brake76is energized via electrical current, the brake76is moved to the “disengaged status,” and the shaft72can rotate about the axis A. However, the brake76is normally in the “engaged status” to prevent movement of the shaft72, the mechanical coupling70, and thus the closure panel20.

When the electromechanical brake76is in the “engaged status,” as shown inFIG. 9, such as when the window20is fully closed, for example, the coil assembly82is de-energized by the absence of electrical current supplied thereto. As such, no current or energy is provided from the controller74to the coil assembly82of the brake76, and thus the spring force imparted by the spring member85biases the second friction plate84into frictional contact with the first friction plate83to prevent the first friction plate83, and thus the shaft72, from rotating about the axis A. By preventing rotation of the shaft72, the brake76also prevents movement of the mechanical coupling70. Accordingly, the window20or other closure panel20remains closed.

To disengage the brake76and move the brake76from the “engaged status” to the “disengaged status,” a signal or command is selectively sent to controller74. A user of the vehicle10can initiate sending a signal or command to the controller74to selectively release the brake76, and thus allow the closure panel20to be freely moved to a new position, for example to an open or closed position. A switch, key fob, button, sensor, or any other device in the vehicle10or associated with the vehicle10can be used to send the signal to the controller74. Upon receiving the signal, the controller74provides energy in the form of electrical current to the coil assembly82and also to the motor28,28′. Upon energizing the electromagnetic coil assembly82via electrical current flowing through the wire winding94, a magnetic field is produced as a result of Ampere's law. The magnetic field exerts a magnetic force on the second friction plate84, which is sufficiently strong to overcome the spring force of the spring member85, and thus the magnetic force pulls and slides the second friction plate84axially away from and out of contact from the first friction plate83. With the second friction plate84being axially spaced from the first friction plate83(FIG. 10), the brake76is brought to the “disengaged status,” thereby allowing the first friction plate78, the shaft72, the mechanical coupling70to move under a suitable externally applied force. As such, once the second friction plate84is disengaged from the first friction plate83, the energy commanded by the controller74and provided to the motor28,28′ causes the shaft72and the first friction plate83to rotate about the axis A. With the second friction plate84no longer being in contact with the first friction plate83, the shaft72and first friction plate83are able to rotate freely about the axis A. The shaft72thusly drives the mechanical coupling70. Once the closure panel20reaches the closed, or another predetermined position, a signal is selectively sent from controller74to cease the supply of the energy to the motor28,28′ and the coil assembly82, thereby de-energizing the coil assembly82, and thus causing the magnetic force from the coil assembly82to dissipate, thereby causing the second friction plate84to move under the bias of the spring member85into frictional engagement with the first friction plate83. Accordingly, the brake76is again brought to the “engaged status” to prevent rotation of the shaft72of the motor28,28′ and thus maintain the closure panel20in the desired position.

The controller74includes a motor control circuit107configured to control the motor28,28′ and a brake control circuit108configured to control the electromechanical brake76. In addition, the switch109(e.g., a window regulator switch) and/or BCM137are shown to provide the motor movement command to the controller74(e.g., in the normal drive state).

The actuation system27of the present disclosure can also be operated manually. If manual operation is performed, the controller74may sense movement from the at least one sensor114a,114b,114cprovided for the motor28,28′ and releases the electromechanical brake76in the same manner as the power operation described above. If all power is lost, for example if the vehicle batteries are dead, then the braking torque is limited to a maximum allowing a slip condition. This will allow the closure panel20to be opened or closed with higher than normal manual forces. Furthermore, the controller74is further configured to monitor the availability of a main power source110and operate in one of the normal drive state and the back drive state accordingly. If the main power source110is normal (i.e., nota low battery or no battery condition), the electromechanical brake assembly76is off (power applied) when the motor28,28′ is on (power applied). Also, if the main power source110is normal, the electromechanical brake assembly76is on (power removed) when the motor28,28′ is off (power removed). However, if the main power source110is not normal (i.e., a low battery or no battery condition), the electromechanical brake assembly76is on (power removed, spring) when the motor28,28′ is off (power removed)

As discussed above with reference toFIG. 7C, the motor28,28′ can brake, resist, or stop movement of the mechanical coupling70and closure panel20in the back drive state. To provide such operation, the motor28,28′ is a brushless direct current electric motor28′ and the controller74is configured to provide field oriented control (FOC) methodology, discussed in more detail below.

As schematically shown inFIG. 11, the brushless DC (Direct Current) electric motor28′ or simply brushless electric motor28′ includes a number of stator windings112a,112b,112c(three in the example, connected in a star configuration), and a rotor113, having two poles (‘N’ or North and CS' or South) in the example, which is operable to rotate with respect to the stator windings112a,112b,112c. The rotation of the rotor113, which may be connected to an output shaft (e.g., shaft72), which is in operable communication with the mechanical coupling70or other mechanism or transmission for imparting a movement to the closure panel20, such as window20as illustrated inFIG. 2.

Control of the brushless electric motor28′ envisages electrical periodical switching of the generated currents Ia, Ib, Ic flowing in the stator windings112a,112b,112cas energized by a DC power source e.g. main power source110in electrical communication with the windings112a,112b,112c, in order to maintain the rotation of the rotor113via the resulting magnetic interaction. For example, a controller unit111of the actuation system27includes the controller74(e.g., microprocessor133), a three-phase inverter134, and a PWM (Pulse Width Modulation) unit135including PWM drivers135a, coupled to the phase stator windings112a,112b,112c. In a known manner, here not discussed in detail, the three-phase inverter134includes three pairs of power transistor switches136for each stator winding112a,112b,112c, which are controlled by the PWM unit135so as to drive the respective phase voltages either at a high (ON) or a low (OFF) value, in order to control the average value of related voltages/currents energizing the stator windings112a,112b,112c. When the stator windings112a,112b,112care energized in a sequential order and magnitude, as determined by the microprocessor133controlling the PWM unit135, a moving magnetic flux is generated which shifts clockwise or counterclockwise. This moving magnetic flux interacts with the magnetic flux generated by the permanent magnetic rotor113to cause the rotor113to rotate. The rotational torque acting on the rotor113will impart a movement of the shaft72.

The control action may utilize knowledge of the position of the rotor113, during its rotation in order to control the energizing voltage/current pattern to be applied to the windings112a,112b,112c, also known as commutation. Accordingly, the actuation system27can include the at least one sensor (e.g., Hall effect sensor114a,114b,114c) coupled to the motor28,28′ for detecting movement of the motor28,28′ and consequently the closure panel20, shown schematically as114a,114b,114c, are circumferentially arranged with respect to the stator windings112a,112b,112c(e.g., with an angular distance of 120° of separation between them), in order to detect the position of the rotor113, and electrically communicate the detected signals to the controller74via the electrical lines117a,117b,117c. For example, using three on/off Hall position sensors114a,114b,114c, the magnetic position of the rotor113may be detected for six different radial zones, and in particular at precise position of the rotor113, as schematically shown inFIG. 12(where the different codes corresponding to the outputs provided by the position sensors114a,114b,114care shown for each zone). Other numbers of Hall position sensors may be provided. The commutation sequence is determined by the controller74based on the relative positions of stator115and rotor113, as measured by the either Hall-effect position sensors114a,114b,114cor a magnitude of the back electromagnetic force (EMF) generated as the rotor113rotates as part of a sensor-less position detection technique. The control action may alternative utilize knowledge of the position of the window20, lifterplates36, cable drum30, or other components moved as a result of the rotation of the rotor113. Also in lieu of hall sensors114a,114b,114c, one or more resolvers131(FIG. 11) may be utilized for determining the position of the rotor113(e.g., mounted to shaft72). Resolvers131, for example, provide more accuracy and consequently less movement of the rotor113(e.g., due to the movement of the window20) would lead to a triggering of the braking.

Now referring toFIG. 13in addition toFIGS. 11 and 12, control of the brushless electric motor28′ may be implemented in a sinusoidal drive mode, whereby the brushless electric motor28′ is supplied by three-phase pulse width modulation (PWM) voltages modulated to obtain phase currents Ia, Ib, Ic of a sinusoidal shape in the stator windings112a,112b,112c, or coils, as schematically shown. With this sinusoidal commutation, all three electrical lines117a,117b,117cconnected with the stator windings112a,112b,112cand the PWM Unit135, are energized (e.g., permanently) with sinusoidal currents Ia, Ib, Ic, that are 120 degrees out of phase with each other. The resulting effect of the supplied current through the stator windings112a,112b,112cis the generating of a North/South magnetic field that rotates inside the motor stator115as the currents Ia, Ib, Ic are varied. The commutation process of switching the current flowing through the stator windings112a,112b,112c, is calculated by the controller74controlling the PWM unit135(MOSFETs136).

A memory unit138may be included as part of controller74(i.e., microprocessor133) for storing instructions and algorithms (e.g., code) for execution by the controller74of the motor control methods and techniques as described herein. While memory chip138is shown as part of the controller74, it could instead be separate. Instructions and code stored on the memory module138may also be related to various system modules, for example application programming interfaces (API) modules, drive API, digital input output API, Diagnostic API, Communication API, and communication drivers for LIN communications and CAN bus communications with the BCM137or other vehicle system. While modules may be described as being loaded into the memory unit138, it is understood that the modules could be implemented in hardware and/or software.

The instructions and algorithms (e.g., code) for execution by the controller74of the motor control methods and techniques as described herein may relate to the control of the three-phase inverter134(including Field Effect Transistors, such as power transistor switches136). The control of the three-phase inverter134provides coordinated power (e.g., sinusoidal voltages to generate currents Ia, Ib, Ic) to the motor28′ e.g. FETS136controlled as load switches to connect or disconnect a source of electrical energy or main power source110(voltage/current) as controlled by the controller74or a FET driver to control the motor28′ in a manner as will be illustratively described below. Illustratively, the controller74is electrically directly or indirectly connected to the three-phase inverter134for control thereof (e.g. for controlling of FET switching rate). The three-phase inverter134is shown as illustratively connected to the motor28′ via the three electrical lines117a,117b,117c. Sensed current signals as well as back EMF voltage signals generated by the rotation of the rotor113may also be illustratively received by the controller74through the same electrical lines117a,117b,117cand monitored by the current circuits139coupled to the motion trigger140of the microprocessor133.

The controller74is configured to implement a Field Oriented Control (FOC) method or algorithm as stored in memory138as instructions and as executed by the controller74, for controlling the brushless electric motor28′. With FOC (or Vector Control) brushless motor techniques, as described herein, the torque and the flux can be controlled independently for braking to control the force moving the window20, as well as improving motor starting, improving motor stopping, and improving motor reversing.

Referring now toFIGS. 14-18, the Field Oriented Control brushless motor technique optimize the torque generated by the rotor113over the angles of rotation of the rotor113relative to the windings112a,112b,112c. The commutated currents Ia, Ib, Ic supplied to the windings112a,112b,112cwill generate a stator field99that is targeted to be orthogonal to the field of the rotor113. The optimal direction of the net stator field force155to maximize torque of the rotor113rotation is illustrated as arrow157which acts to rotate the rotor113. The sub-optimal direction of the net stator field force155is illustrated as arrow159which acts to outwardly pull on the rotor113and will generate no rotational torque on the rotor113. When magnetic fields99and field144are parallel, the net stator field force155will only include the net stator field force155component as indicated by arrow159, and therefore no torque is produced on the rotor113. When magnetic fields99and field144are orthogonal, the net stator field force155will only include the net stator field force155component as indicated by arrow157, and therefore maximum torque is produced on the rotor113. Field Oriented Control (or Vector Control) targets to eliminate (e.g., 0) the pulling force159to maximize the torque force157.

In order to maximize the torque in such a manner, the currents Ia, Ib, Ic, and voltages applied to the windings112a,112b,112care controlled separately and as a function of the actual angular position θ of the rotor113relative to the windings112a,112b,112c, in order to align the stator field99in an orthogonal orientation with the rotor magnetic field144. The phase shifted resultant stator current Is can be mathematically decomposed into two components as illustrated inFIGS. 14-16: a Quadrature current (Iq), or also referred to as torque current, which induces in the rotor113rotation according to the orthogonal force157acting on the rotor113; and a Direct current (Id), or also referred to as flux current which induces the outward pulling force159on the rotor113. The Field Oriented Control technique is concerned with adjusting these 2-axis domain components Id, Iq which are transformed using a transform function into the stator 3-axis domain as the three current signals Ia, Ib, Ic in order to reduce or eliminate the flux current Id to nil, leaving only the torque current Iq to generate the stator magnetic field99in quadrature with the rotor's quadrature axis as shown by arrow157. By adjusting the supplied motor currents and voltages with reference to the rotor's flux or direct and quadrature axes, precise control of the rotor rotation results, such as decreases or increases in the rotor rotation can be precisely and quickly controlled since the torque current (Iq) can be adjusted based on the position θ of the rotor113which remains synchronized during rotation, which may be exactly determined by the use of the Hall sensor signals as will be described herein below. FOC control can therefore provide faster dynamic response than compared with brushed motor control, for example those using trapezoidal commutated control since the torque current Iq is calculated based on the exact position of the rotor113. Faster motor response times are desirable for window regulator applications.

As best shown inFIG. 17, modules or units of the vector control system202of the controller74are provided to implement the field oriented and thus may be embodied in software as instructions stored in memory unit138as executed by the controller74. The vector control system202is configured to receive a target torque current Ĭq based on an actual angular velocity ω of the brushless electric motor28′ (e.g., determined using Hall sensors114a,114b,114cofFIG. 11, as described in more detail below) and a sensed first phase current Ia and a second phase current Ib and a third phase current Ic from the brushless electric motor28′ (e.g., currents flowing through windings/coils112a,112b,112c, which may include current components induced as a result of the rotation of the rotor113in addition to currents supplied to the windings/coils112a,112b,112cand sensed using an analog to digital converter). The vector control system202is also configured to determine an alpha stationary reference frame voltageα and a beta stationary reference frame voltage based {circumflex over (V)}β based on the sensed first phase current Ia, second phase current Ib, and third phase current Ic in response to a Hall sensor or motion trigger140(rising edge or falling edge) based on a plurality of Hall sensor signals from the plurality of Hall sensors114a,114b,114c. For example, the Hall sensor signals can be received by an interrupt handler141(FIG. 18) at an interrupt port of the controller74. So, the torque voltage command {circumflex over (V)}q and the flux linkage voltage command {circumflex over (V)}d are updated once the Hall sensor or motion trigger140detected.

Consequently, the torque FOC vector (Vd, Vq) is calculated based on the exact known position of the rotor113and moment to maximize torque applied to the rotor113. This torque calculation is only done six times per revolution at each Hall detection (e.g., if three Hall sensors114a,114b,114cprovided), compared to resolvers where calculations occur thousands of times per revolution. As a result, vector control system202uses the digital signals of the Hall sensors114a,114b,114cto provide high accuracy of position θ of the rotor113which a resolver analog signal does not provide, and the FOC calculations are computationally less demanding resulting in quicker calculations and response times, a more efficient torque vector (Vd, Vq), as well as less expensive CPUs and processors.

The vector control system202maintains the alpha stationary reference frame voltageα and the beta stationary reference frame voltage {circumflex over (V)}β. In addition, the vector control system202is configured to output a first phase pulse width modulation signal PWMa and a second phase pulse width modulation signal PWMb and a third phase pulse width modulation signal PWMc to the brushless electric motor28based on the alpha stationary reference frame voltageα and the beta stationary reference frame voltage {circumflex over (V)}β. In more detail, the vector control system202includes a first proportional-integral control unit204configured to receive the target torque current Ĭq based on the actual angular velocity ω of the brushless electric motor28and a torque current drawnq and output a torque voltage command {circumflex over (V)}q using the target torque current Ĭq the torque current drawnq. An inverse Park transformation unit206is coupled to the first proportional-integral control unit204and is configured to receive an actual angular position θ of the brushless electric motor28and transform the torque voltage command {circumflex over (V)}q and a flux linkage voltage command {circumflex over (V)}d to an alpha stationary reference frame voltage {circumflex over (V)}α and a beta stationary reference frame voltage {circumflex over (V)}β using an inverse Park transformation. A switching states or space vector pulse width modulation unit208is coupled to the inverse Park transformation unit206and to the brushless electric motor28and is configured to convert the alpha stationary reference frame voltage {circumflex over (V)}α and a beta stationary reference frame voltage {circumflex over (V)}β to 3-phase stator reference signals and determine and output a first phase pulse width modulation signal PWMa and a second phase pulse width modulation signal PWMb and a third phase pulse width modulation signal PWMc to the brushless electric motor28′. The switching states vector pulse width modulation unit208performs a space vector pulse width modulation calculation based on magnitudes of the calculated torque voltage command {circumflex over (V)}q and the flux linkage voltage command {circumflex over (V)}d when triggered by the motion trigger140(rising or falling edges of digital signals from the Hall sensors114a,114b,114c) and the torque voltage command Vq and the flux linkage voltage command {circumflex over (V)}d are transformed based on the angle of rotor113over the sector of the rotation of the rotor113. Both the switching states or space vector pulse width modulation unit208and the inverse Park transformation unit206are also coupled to and triggered by a pulse width modulation (PWM) trigger209.

The vector control system202also includes a Clarke transformation unit210coupled to the brushless electric motor28′ that is configured to receive the first phase current Ia and the second phase current Ib and the third phase current Ic from the brushless electric motor28′ and determine and output an alpha stationary reference frame currentα and a beta stationary reference frame currentβ using a Clarke transformation (e.g., the Clarke transformation will convert the balanced three-phase currents sensed from the 3-axis system of the windings112a,112b,112c, into two-phase quadrature stator currents of a 2-axis coordinate system). A Park transformation unit212is coupled to the Clarke transformation unit210and is configured to receive the alpha stationary reference frame currentα and the beta stationary reference frame currentβ and determine and output the torque current drawnq and a field flux linkage current drawnd using a Park transformation.

A second proportional-integral control unit214is coupled to the inverse Park transformation unit206and the Park transformation unit212and is configured to receive a reference flux linkage currentdrefand the flux linkage current drawnd and determine and output the flux linkage voltage command {circumflex over (V)}d to the inverse Park transformation unit206.

Referring back to the vector control system202, the Clarke transformation unit210has a first phase current input258and a second phase current input260and a third phase current input262each coupled to the brushless electric motor28′ for receiving the first phase current Ia and the second phase current Ib and the third phase current Ic and an alpha stationary reference frame current output264coupled to the Park transformation unit212for outputting the alpha stationary reference frame currentα and a beta stationary reference frame current output266coupled to the Park transformation unit212for outputting the beta stationary reference frame currentβ.

The Park transformation unit212has an alpha stationary reference frame current input268coupled to the alpha stationary reference frame current output264of the Clarke transformation unit210for receiving the alpha stationary reference frame currentα and a beta stationary reference frame current input270coupled to the beta stationary reference frame current output266of the Clarke transformation unit210for receiving the beta stationary reference frame currentβ. The Park transformation unit212also has a torque current drawn output272coupled to the first proportional-integral control unit204for outputting the torque current drawn torque current drawnq and a field flux linkage current drawn output274coupled to the second proportional-integral control unit214for outputting the field flux current drawnd.

The second proportional-integral control unit214has a second reference input276being the reference flux linkage currentdreference(e.g., reference flux linkage current=0 for reasons as described herein above to eliminate the force acting on the rotor113depicted by arrow159) and a second measured input278coupled to the flux linkage current drawn output274of the Park transformation unit212for receiving the flux linkage current drawnd and a flux linkage voltage output280coupled to the inverse Park transformation unit206for outputting the flux linkage voltage command {circumflex over (V)}d.

The first proportional-integral control unit204has a first reference input282for receiving the target or desired torque current Ĭq. The first proportional-integral control unit204also has a first measured input284coupled to the torque current drawn output272for receiving the torque current drawnq and a torque voltage output286coupled to the inverse Park transformation unit206for outputting the torque voltage command {circumflex over (V)}q. It is hereby recognized that control system200takes advantage of the inherent properties of the brushless electric motor28′, specifically the property that when the brushless electric motor28′ is slowed, for example by a pinch event, the torque current drawnq will increase. The PI integration of the difference between the limited torque current Ĭq and this inherently increased torque current drawnq as represented inFIG. 18by arrow F will result in a lowered torque voltage command {circumflex over (V)}q to be applied to the motor28′, thus further reducing measured angular velocity ω and inertia in the actuation system27. So, the Hall sensors114a,114b,114cdetect the position of the rotor113, as shown and the microcontroller133calculates the flux linkage voltage command {circumflex over (V)}d and torque voltage command {circumflex over (V)}q to eliminate the direct or flux current Id, such that only the perpendicular force F on the rotor113will result (e.g., maximum torque on the rotor113applied by the filed generated in the coils112a,112b,112cby the transformed flux linkage voltage command {circumflex over (V)}d and torque voltage command {circumflex over (V)}q).

The inverse Park transformation unit206has a first inverse Park input288coupled to the torque voltage output286of the first proportional-integral control unit204for receiving the torque voltage command {circumflex over (V)}q. The inverse Park transformation unit206additionally has a second inverse Park input290coupled to the flux linkage voltage output280of the second proportional-integral control unit214for receiving the flux linkage voltage command {circumflex over (V)}d and a third inverse Park input292coupled to the adder output252of the adder unit246of the position determining system216for receiving the actual angular position θ (or estimated angle of rotor13). The inverse Park transformation unit206also has an alpha stationary reference frame voltage output294coupled to the switching states vector pulse width modulation unit208for outputting the alpha stationary reference frame voltage {circumflex over (V)}α and a beta stationary reference frame voltage output296coupled to the switching states vector pulse width modulation unit208for outputting the alpha stationary reference frame voltage {circumflex over (V)}β.

The switching states vector pulse width modulation unit208converts the two component alpha stationary reference frame voltage {circumflex over (V)}α and the beta stationary reference frame voltage {circumflex over (V)}β into the three component stator domain to generate the PWM signals to be supplied to each stator winding112a,112b,112c. The switching states vector pulse width modulation unit208has an alpha stationary reference frame voltage input298coupled to the alpha stationary reference frame voltage output294of the inverse Park transformation unit206for receiving the alpha stationary reference frame voltage {circumflex over (V)}α and a beta stationary reference frame voltage input300coupled to the beta stationary reference frame voltage output296of the inverse Park transformation unit206for receiving the beta stationary reference frame voltage {circumflex over (V)}β. The switching states vector pulse width modulation unit208also has a first phase pulse width modulation output302coupled to the brushless electric motor28(e.g., to winding112a) for outputting the first phase pulse modulation signal PWMa and a second phase pulse width modulation output304coupled to the brushless electric motor28(e.g. to winding112b) for outputting the second phase pulse modulation signal PWMb and a third phase pulse width modulation output306coupled to the brushless electric motor28(e.g. to winding112c) for outputting the third phase pulse width modulation signal PWMc.

InFIG. 19A, a manual input movement is applied to the window20, thereby causing a slight movement of the motor28′ (and rotor113). InFIG. 19B, the rotor and stator fields99,144are slightly out of alignment (e.g., the manual movement is just starting to move the rotor113) by θ1. As shown inFIG. 19C, the flux linkage current drawnd is insufficient to resist rotor rotation and the flux linkage current drawnd drops and torque current Iq is induced in the rotor113, naturally opposing the direction of the rotor113. So, a generated torque current307is opposite to the induced torque current Iq bringing the rotor113back into alignment. The at least one sensor (e.g., Hall sensors114a,114b,114c) shown inFIG. 19Bis not triggered yet due to movement of the rotor113.

However, an increased manual input movement can be applied to the window20resulting in braking or resisting of the motor28′ as shown inFIG. 20A. Such a resisting mode is utilized once the rotor and stator fields99,144are out of alignment by θ2(a larger angle than θ1), as shown inFIG. 20B. The controller74is configured to detect the sensor signal from the at least one sensor (e.g. Hall effect sensors114a,114b,114c) triggering the motion trigger140and indicating a manual movement of the shaft72of the motor28′ in the back drive state. The controller74also monitors the first phase current Ia and the second phase current Ib and the third phase current Ic from the motor28′ in the back drive state. The controller74is also configured to calculate a torque current drawnq and a field flux linkage current drawnd based on the first phase current Ia and the second phase current Ib and the third phase current Ic from the motor28′ in response to detecting the sensor signal from the at least one sensor114a,114b,114cindicating the manual movement of the shaft72of the motor28′ in the back drive state.

The controller74then generates a flux linkage voltage command {circumflex over (V)}d and a torque voltage command {circumflex over (V)}q resulting in an opposing torque current opposite the torque current drawnq and minimize the field flux linkage current drawnd in a resisting mode of the back drive state, as best shown inFIG. 20C. The controller74can also generate the flux linkage voltage command {circumflex over (V)}d and the torque voltage command {circumflex over (V)}q resulting in the torque current drawnq being minimized and the field flux linkage current drawnd being maximized in a holding mode of the back drive state shown inFIGS. 21A and 21B.

As best shown inFIGS. 22-25, a method of operating an actuation system27for moving a closure panel20of a vehicle10in one of a normal drive state and a back drive state is also provided. The method includes the steps of detecting a motor movement command using a controller74in the normal drive state. Next, the method includes the step of directly moving the closure panel20in between an open position and a closed position with a motor28,28′ having a shaft72directly and operably connected to a mechanical coupling70connected to the closure panel20based on the motor movement command detected in the normal drive state. The method proceeds by detecting movement of the closure panel20using at least one sensor114a,114b,114ccoupled to the motor28,28′ and the controller74in one of the normal drive mode and the back drive state. The method continues with the step of controlling operation of the motor28,28′ using the controller74based on the movement detected and the motor movement command detected in one of the normal drive mode and the back drive state. The method continues with the step of selectively braking the movement of the closure panel20in between the closed position and the open position based on the movement detected using the controller74in the back drive state.

As discussed above, the motor28,28′ can be the brushless direct current electric motor28′. Thus, as best shown inFIG. 22, the step of selectively braking the movement of the closure panel20in between the closed position and the open position based on the movement detected using the controller74in the back drive state can include steps of400determining whether the movement of the closure panel20is detected and402returning to a start braking step in response to not determining that the movement of the closure panel20is detected. The method can also include the step of404applying power to the brushless direct current electric motor28′ to counter the movement of the closure panel20in response to determining that the movement of the closure panel20is detected. The method can continue with the steps of406waiting for a predetermined period of time (e.g., one second) and408returning to the step of400determining whether the movement of the closure panel20is detected after waiting for the predetermined period of time.

As discussed, the actuation system27can further include an electromechanical brake assembly76coupled to at least one of the mechanical coupling70and the motor28,28′ and electrically coupled to the controller74. The electromechanical brake assembly76is controlled by the controller74to selectively move between an engaged status (in which rotation of the shaft72is hindered for braking movement of the mechanical coupling70and the closure panel20between the closed position and the open position in the back drive state) and a disengaged status (in which the shaft72is permitted to rotate and allow movement of the mechanical coupling70and the closure panel20in the normal drive state).

Consequently, as best shown inFIG. 23, the step of selectively braking the movement of the closure panel20in between the closed position and the open position based on the movement detected using the controller74in the back drive state can include the step of410determining whether the motor movement command is detected. The method can continue by412applying power to the electromechanical brake assembly76to transition the electromechanical brake assembly76to the disengaged status in response to determining that the motor movement command is detected. The method can proceed with the step of414determining that the movement of the closure panel20has stopped (e.g., the shaft72of the motor28,28′ has stopped rotating). The method can then include the step of416removing power from the electromechanical brake assembly76to transition the electromechanical brake assembly76to the engaged status in response to determining that the movement of the closure panel20has stopped. The method can continue with the step of418returning to a start braking step after removing power from the electromechanical brake assembly76.

If, for example, the closure panel20is a window20of a door and the motor28,28′ is a brushless direct current electric motor28′, the method can include steps shown inFIG. 24. Specifically, the method may further include the steps of419monitoring for the motor movement command and420determining whether the motor movement command is detected. Next,421moving the window20in response to determining the motor movement command is detected and422returning to the step of419monitoring for the motor movement command in response to determining the motor movement command is not detected. The method continues with the step of423detecting a sensor signal from the at least one sensor114a,114b,114cindicating a manual movement of the window20in response to not determining that the motor movement command is detected. The method can then continue with the step of424returning to the step of420determining whether the motor movement command is detected in response to not detecting the sensor signal from the at least one sensor114a,114b,114cindicating the manual movement of the window20. The method can then include the step of426executing an electronic motor brake control in response to detecting the sensor signal from the at least one sensor114a,114b,114cindicating the manual movement of the window20. Next, the method can continue with the steps of428waiting for a predetermined period of time and430returning to the step of422detecting a sensor signal from the at least one sensor114a,114b,114cindicating a manual movement of the window20after waiting for the predetermined period of time (such a step can help conserve electrical energy in a vehicle battery, so that the braking is not continuously on).

Referring toFIG. 25, the step of426executing the electronic motor brake control can include the step of432determining that the sensor signal from the at least one sensor114a,114b,114cindicates the manual movement of the window20. The method can then include the step of434executing return braking field oriented control in a resisting mode of the back drive state in response to determining that the sensor signal from the at least one sensor114a,114b,114cindicates the manual movement of the window20(e.g., generate the flux linkage voltage command {circumflex over (V)}d and the torque voltage command {circumflex over (V)}q resulting in the torque current drawnq being minimized and the field flux linkage current drawnd being maximized to oppose rotation direction of the rotor113). Step of434may be optional and the method can directly proceed to a resisting mode in step434upon triggering of the hall sensors Hall sensors114a,114b,114c, for example.

More Specifically, the step of434executing return braking field oriented control in the resisting mode of the back drive state in response to determining that the sensor signal from the at least one sensor114a,114b,114cindicates the manual movement of the window20can include the step of monitoring a first phase current Ia and a second phase current Ib and a third phase current Ic from the motor28′ calculating a torque current drawnq and a field flux linkage current drawnd based on the first phase current Ia and the second phase current Ib and the third phase current Ic from the motor28′ the generating a flux linkage voltage command {circumflex over (V)}d and a torque voltage command {circumflex over (V)}q resulting in an opposing torque current opposite the torque current drawnq and minimize the field flux linkage current drawnd.

Continuing to refer toFIG. 25, the next step of the method can be 436 determining whether the sensor signal indicates that the window20has moved back to an initial position. Then, the method can proceed by438executing return braking field oriented control in a holding mode of the back drive state (e.g., generate the flux linkage voltage command {circumflex over (V)}d and the torque voltage command {circumflex over (V)}q resulting in the torque current drawnq being minimized and the field flux linkage current drawnd being maximized to oppose rotation direction of the rotor113for a predetermined time out period of time) in response to determining that the sensor signal indicates that the window20has moved back to the initial position (such a step can help conserve electrical energy in a vehicle battery, so that the braking is not continuously on).

In more detail, the step of438executing return braking field oriented control in the holding mode of the back drive state in response to determining that the sensor signal indicates that the window20has moved back to the initial position can include the steps of monitoring a first phase current Ia and a second phase current Ib and a third phase current Ic from the motor28′ and calculating a torque current drawnq and a field flux linkage current drawnd based on the first phase current Ia and the second phase current Ib and the third phase current Ic from the motor28′. Next, generating the flux linkage voltage command {circumflex over (V)}d and the torque voltage command {circumflex over (V)}q resulting in the torque current drawnq being minimized and the field flux linkage current drawnd being maximized.

Still referring toFIG. 25, the method can also include the step of440returning to the step of434executing return braking field oriented control in a resisting mode of the back drive state in response to determining that the sensor signal indicates that the window20has not moved back to the initial position.

As discussed above, the actuation system27disclosed herein can be applied to window regulators. Other actuation applications are also contemplated. Although one exemplary operation of resisting and holding of a brushless motor using FOC control is provided, other manners of resisting and holding the rotor of the brushless motor may be provided, for example using a FOC technique with a resolver. Those skilled in the art will recognize that concepts disclosed in association with the example actuation system27can likewise be implemented into many other systems to control one or more operations and/or functions, such as, but not limited to other closure panels including doors and lift gates.