Patent Publication Number: US-8994228-B2

Title: Proximity switch having wrong touch feedback

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to switches, and more particularly relates to proximity switches with enhanced user feedback and user interaction. 
     BACKGROUND OF THE INVENTION 
     Automotive vehicles are typically equipped with various user actuatable switches, such as switches for operating devices including powered windows, headlights, windshield wipers, moonroofs or sunroofs, interior lighting, radio and infotainment devices, and various other devices. Generally, these types of switches need to be actuated by a user in order to activate or deactivate a device or perform some type of control function. Proximity switches, such as capacitive switches, employ one or more proximity sensors to generate a sense activation field and sense changes to the activation field indicative of user actuation of the switch, typically caused by a user&#39;s finger in close proximity or contact with the sensor. Capacitive switches are typically configured to detect user actuation of the switch based on comparison of the sense activation field to a threshold. 
     Switch assemblies often employ a plurality of capacitive switches in close proximity to one another and require that a user select a single desired capacitive switch to perform the intended operation. Users frequently activate the wrong switch, such as activating multiple switches simultaneously, particularly when the user interface devices are small and the switches are close together. In some applications, such as in an automobile, the driver of the vehicle has limited ability to view the switches due to driver distraction and therefore may inadvertently operate the switch in a wrong manner. Accordingly, it is desirable to provide for a proximity switch arrangement, which enhances the use of the proximity switches by a person, such as a driver in a vehicle. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, a method of activating a proximity switch assembly is provided. The method includes the steps of sensing activation of one or more proximity switches and detecting an allowed activation of one of the proximity switches. The method further includes the steps of performing an action in response to the detected allowed activation and detecting an attempted activation of the one or more proximity switches that is not allowed. The method further includes the step of generating a user perceived feedback indicative of the activation that is not allowed. 
     According to another aspect of the present invention, a proximity switch assembly is provided. The proximity switch assembly comprises a plurality of proximity switches each providing a sense activation field and control circuitry processing the sense activation field of each proximity switch to sense activation. The control circuitry detects an allowed activation of one of the proximity switches and further detects an attempted activation that is not allowed. The proximity switch further includes an output coupled to a device to perform a function when an allowed activation is detected. The proximity switch also includes a feedback device for generating a user perceived feedback when an attempted activation that is not allowed is detected. 
     These and other aspects, objects, and features of the present invention will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a perspective view of a passenger compartment of an automotive vehicle having an overhead console employing a proximity switch assembly having user perceived feedback, according to one embodiment; 
         FIG. 2  is an enlarged view of the overhead console and proximity switch assembly shown in  FIG. 1 ; 
         FIG. 3  is an enlarged cross-sectional view taken through line III-III in  FIG. 2  showing the proximity switches in relation to a user&#39;s finger; 
         FIG. 4  is a block diagram illustrating the proximity switch assembly having user perceived feedback, according to one embodiment; and 
         FIG. 5  is a flow diagram illustrating a routine for providing user perceived feedback based on activation of the proximity switches, according to one embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As required, detailed embodiments of the present invention are disclosed herein; 
     however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to a detailed design; some schematics may be exaggerated or minimized to show function overview. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. 
     Referring to  FIGS. 1 and 2 , the interior of an automotive vehicle  10  is generally illustrated having a passenger compartment and a switch assembly  20  employing a plurality of proximity switches  22  having user perceived feedback, according to one embodiment. The vehicle  10  generally includes an overhead console  12  assembled to the headliner on the underside of the roof or ceiling at the top of the vehicle passenger compartment, generally above the front passenger seating area. The switch assembly  20  has a plurality of proximity switches  22  arranged close to one another in the overhead console  12 , according to one embodiment. The various proximity switches  22  may control any of a number of vehicle devices and functions, such as controlling movement of a sunroof or moonroof  16 , controlling movement of a moonroof shade  18 , controlling activation of one or more lighting devices such as interior map/reading and dome lights  32 , and various other devices and functions. However, it should be appreciated that the proximity switches  22  may be located elsewhere on the vehicle  10 , such as in the dash panel, on other consoles such as a center console, integrated into a touch screen display for a radio or infotainment system such as a navigation and/or audio display, or located elsewhere onboard the vehicle  10  according to various vehicle applications. 
     The proximity switches  22  are shown and described herein as capacitive switches, according to one embodiment. Each proximity switch  22  includes at least one proximity sensor that provides a sense activation field to sense contact or close proximity of a user in relation to the one or more proximity sensors, such as a swiping motion by a user&#39;s finger. Thus, the sense activation field of each proximity switch  22  is a capacitive field in the exemplary embodiment and the user&#39;s finger has electrical conductivity and dielectric properties that cause a change or disturbance in the sense activation field as should be evident to those skilled in the art. However, it should also be appreciated by those skilled in the art that additional or alternative types of proximity sensors can be used, such as, but not limited to, inductive sensors, optical sensors, temperatures sensors, resistive sensors, the like, or a combination thereof. Exemplary proximity sensors are described in the Apr. 9, 2009, ATMEL® Touch Sensors Design Guide, 10620 D-AT42-04/09, the entire reference hereby being incorporated herein by reference. 
     The proximity switches  22  shown in  FIGS. 1 and 2  each provide control of a vehicle component or device or provide a designated control function. One or more of the proximity switches  22  may be dedicated to controlling movement of a sunroof or moonroof  16  so as to cause the moonroof  16  to move in an open or closed direction, tilt the moonroof, or stop movement of the moonroof based upon a control algorithm. One or more other proximity switches  22  may be dedicated to controlling movement of a moonroof shade  18  between open and closed positions. Each of the moonroof  16  and shade  18  may be actuated by an electric motor in response to actuation of the corresponding proximity switch  22 . Other proximity switches  22  may be dedicated to control other devices, such as turning an interior map/reading light on, turning an interior map/reading light off, turning a dome lamp on or off, unlocking a trunk, opening a rear hatch, or for defeating a door light switch. Additional controls via the proximity switches  22  may include actuating door power windows up and down. Various other vehicle controls may be controlled by way of the proximity switches  22  described herein. 
     The proximity switch assembly  20  includes one or more user perceived feedback devices for generating user perceived feedback when an attempted activation of a proximity switch is not allowed. The user perceived feedback devices may include an audible tone generator such as one or more vehicle speakers  36  shown installed in the doors of the vehicle. Any of the vehicle equipped speakers or other audible tone generators may be employed to provide an audible tone to the user upon wrong touch activation of the switch assembly  20 . Other feedback devices may include a visual display, such as navigation or radio display  38  shown installed in the vehicle. The visual display  38  may display text or icons as feedback indicative of a wrong touch of the proximity switch assembly  20 . Further feedback devices may include a vibratory or tactile generator  40  for providing a vibration as a feedback. The vibratory generator  40  may be integrated within the proximity switch assembly  20  or within the individual proximity switches  22  to generate vibration to the user&#39;s finger, according to one embodiment. According to other embodiments, the vibratory generator  40  may be located within the steering wheel  14  of the vehicle, the vehicle seat, or other point of contact with the user to provide a vibration that is perceived by the user upon wrong touch of the proximity switch assembly  20 . A further feedback device may include one or more indicator lights  42  for providing a visual light indication as a feedback indicative of a wrong touch activation of the proximity switch assembly. The indicator light  42  may include a dedicated light installed in the instrument panel cluster, as shown, or other dedicated or shared lighting devices including mood or ambient lighting, dome lighting, map reading lights, electronic display lighting, and other lighting available and viewable by a user of the proximity switch assembly  20 . 
     Referring to  FIG. 3 , a portion of the proximity switch assembly  20  is illustrated having three serial arranged proximity switches  22  in close relation to one another in relation to a user&#39;s finger  60  during a wrong touch activation of the switch assembly  20 . Each proximity switch  22  includes one or more proximity sensors mounted on a substrate  54  for generating a sense activation field  50 . A contact surface  52  such as a film covers the proximity switches  22 . In the embodiment shown, adjacent sense activation fields  50  generated by adjacent proximity switches  22  overlap slightly. When a user, such as the user&#39;s finger, enters the activation field, the proximity switch assembly  20  detects the disturbance to the activation field and determines an activation of the corresponding proximity switch  22 . However, when a user simultaneously contacts two switches, such that the finger  60  simultaneously enters activation fields  50  for adjacent proximity sensors, a wrong touch condition exists. When a wrong touch condition is detected, activation of the proximity switches is not allowed and a user perceived feedback is provided to the user to let the user know of the wrong touch condition. A wrong touch condition may also exist when a user activates a switch  22  for which an action cannot be performed. This may include a situation where the user activates a switch  22  to open a moonroof, however, the moonroof is already in the fully open position such that the action cannot be performed. Another example of a wrong touch condition for an action that cannot be performed is the attempted activation of a proximity switch  22  to open the moonroof when such action is prohibited by a rain sensor detecting the presence of rain such that the action is not allowed. It should be appreciated that other examples of wrong touch conditions may exist. 
     Referring to  FIG. 4 , the proximity switch assembly  20  is illustrated according to one embodiment. A plurality of proximity switches  22  are shown providing inputs to a controller  24 . The controller  24  may include control circuitry, such as a microprocessor  26  and memory  28 . The control circuitry may include sense control circuitry processing the activation field to sense user activation of the switch by comparing the activation field to a threshold. It should be appreciated that other analog and/or digital control circuitry may be employed to process the activation field, determine user activation, initiate an action and generate user perceived feedback. The controller  24  provides an output signal to one or more devices that are configured to perform dedicated actions responsive to correct activation of a proximity switch. For example, the one or more devices may include a moonroof  16  having a motor to move the moonroof panel between open and closed and tilt positions, a moonroof shade  18  that moves between open and closed positions, and light devices  34  that may be turned on and off. Other devices may be controlled such as a radio for performing on and off functions, volume control, scanning, and other types of devices for performing other dedicated functions. One of the proximity switches  22  may be dedicated to actuating the moonroof closed, another proximity switch  22  may be dedicated to actuating the moonroof open, and a further switch  22  may be dedicated to actuating the moonroof to a tilt position, all of which would cause a motor to move the moonroof to a desired position. The moonroof shade  18  may be opened in response to one proximity switch  22  and may be closed responsive to another proximity switch  22 . 
     The controller  20  provides an output signal to one or more user perceived feedback devices  30  to generate a perceived feedback to a user. According to one embodiment, the user perceived feedback devices  30  may include an audible tone generator  36 , such as a speaker, for generating an audible signal. According to another embodiment, the one or more user feedback devices  30  may include a tactile vibratory generator  40  for generating a vibration of the proximity switch pad or some other device or surface, such as a steering wheel or an armrest or seat upon which the user is seated in. According to a further embodiment, the feedback device  30  may include one or more indicator lights  42  for providing a light output. Further, the feedback device  30  may employ a visual display  38  to display feedback information in the form of text or icons. The user perceived feedback devices  30  provide an audible tone, vibration, light and/or visual display to the user in response to activation of the one or more proximity switches. 
     When a user attempts to activate a switch with a wrong touch condition, a first or wrong touch feedback is generated to indicate to the user that the switch was wrongly activated. A wrong touch activation may include simultaneous activation of two switches, according to one embodiment. The user perceived feedback device  30  may generate a second or action completed feedback to the user when the action actuated has completed the action. A third or right touch feedback may be generated when an allowed activation of a proximity switch is detected. 
     The controller  42  processes one or more routines including routine  100  to generate user perceived feedback based on activation of one or more of the proximity switches  22 . The controller monitors the proximity switches for an activation of one or more of the proximity switches and performs the dedication action when a right touch activation is detected. When an activation is properly detected, a right touch feedback may be provided by any of the feedback devices  30 . The controller  42  also monitors for proximity sensors  22  for the presence of a wrong touch activation of the proximity sensor assembly and generates a wrong touch feedback in response thereto. The wrong touch condition may be due to an ambiguous input such as a simultaneous activation of two or more switches, or may be the activation of a switch for which an action cannot be performed. The feedback generated for a wrong touch is different than the feedback generated for a right touch so that the user may decipher between wrong touch and right touch activations of the proximity switch assembly  20 . The controller  42  further determines when the action actuated by the activation of a proximity switch is complete and provides in response thereto an action complete feedback via one or more of the feedback devices  30 . The action complete feedback is different than the wrong touch feedback and the right touch feedback such that a user may decipher the differences therebetween. 
     Referring to  FIG. 5 , the control routine  100  is illustrated, according to one embodiment. 
     Routine  100  begins at step  102  and proceeds to step  104  to monitor the proximity sensor outputs for each switch. Next, at decision step  106 , routine  100  detects activation of one or more proximity switches and, if no activation is detected, returns to step  104 . If the activation of one or more proximity switches is detected, routine  100  proceeds to decision step  108  to look for an ambiguous input. The ambiguous input may include the attempted simultaneous activation of two or more proximity switches. If an ambiguous input is detected, routine  100  generates the wrong touch feedback at step  110  and then returns at step  122 . If no ambiguous input is detected, routine  100  proceeds to decision step  112  to determine if the action dedicated to that activated proximity switch is allowed and, if not, generates a wrong touch feedback at step  110 , and then returns at step  122 . Accordingly, either an ambiguous input or activation or a switch for which an action is not allowed are deemed to be wrong touch activations for which an action cannot be performed. In response thereto, a wrong touch feedback is generated by one or more of the feedback devices including the audible tone generator  36 , visual display  38 , vibratory generator  40 , and indicator light(s)  42 . The wrong touch feedback may be a user perceived alert type feedback that a user would perceive as an incorrect activation of the proximity switch assembly  20 . 
     If no wrong touch activation exists, routine  100  proceeds to step  114  to generate a right touch feedback. A right touch feedback may be generated with any one or more of the feedback devices to provide a second more pleasant feedback recognizable by a user as proper activation of a proximity switch for which an action can be performed. At step  116 , the action responsive to the switch activation is performed. Next, routine  100  proceeds to step  118  to determine if the action is complete and, if not, returns to step  122 . If the action is complete, routine  100  then generates an action complete feedback via one or more of the feedback devices  30 . The action complete feedback is a third pleasant tone feedback recognizable by a user as completion of the action in response to activation of the proximity switch. 
     According to another embodiment, the right touch feedback may be generated to provide multiple levels of feedback, such as a progressive feedback. For example, when two signal channels for adjacent capacitive switches are at a substantially similar signal level, a wrong touch feedback may be provided at a first level, however, when one channel is significantly greater than the other channel, the wrong touch feedback may be at a second lower level relative to the first feedback. This may indicate to the operator that the wrong touch is not as severe or significant when one signal channel is substantially greater than another indicative that the correct signal was substantially activated. This may help to provide feedback to the user so that the user may understand why the input is deemed wrong and how to modify hand posture to get the action recognized correctly. According to another example, for a non-allowed action, multiple levels of progressive feedback may be provided, such as to provide a first higher feedback when a user attempts to open a moonroof while the vehicle is in a car wash and provides a second lower feedback when the user is trying to close a moonroof that is already closed. 
     Accordingly, the proximity switch arrangement  20  advantageously provides for enhanced user interaction and user perceived feedback to a user to indicate whether the proximity switches have been properly activated to perform an action that is available. The switch assembly  20  allows users to be trained on use of the switch arrangement with feedback. Additionally, the switch arrangement may be less distractive by providing the user with perceived feedback, which is particularly advantageous in automotive applications. 
     It is to be understood that variations and modifications can be made on the aforementioned structure without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.