Abstract:
A haptic system including a compliant member which limits the direction of motion of an interface surface providing haptic feedback to motion along a single axis. The compliant member allows for easy assembly, reduced ports, lighter weight and improved longevity and performance. The compliant member typically has a longitudinal extent that is greater than its lateral extent and height, and its height is greater than its lateral extent.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Technical Field 
         [0002]    The present invention is directed to a robust and compact haptic feedback system, more specifically, a haptic system that economically and reliably constrains movement of the interface surface to a single axis of motion to minimize potential for damage to a haptic feedback driver and more specifically, to a compliant mounting apparatus or member for haptic feedback systems that is capable of constraining motion of a haptic interface or interface surface in a single axis of movement. 
         [0003]    2. Discussion 
         [0004]    To improve and enhance ability to interface with various electronic devices, many manufacturers have added haptic feedback systems to various devices. In general, haptic feedback systems interface with a user via the sense of touch by applying forces, vibrations, and/or motions to the user. While haptic feedback devices can be used in a variety of devices, one particular area where haptic feedback is useful is touch screen interfaces or compact mechanical button interfaces, where the ability to visually interact is limited or reduced, such as for operators of vehicles, or smaller devices where size is a concern, such as inputs for cell phones and other portable electronic device. More specifically, haptic feedback systems are very helpful in providing the user with feedback without visual confirmation by the user, especially where the input member is too small to easily see, such as a touch screen keypad on a mobile phone. This haptic feedback is very useful in situations where the ability of the user to visually confirm actions may be constrained such as an operator of a vehicle attempting to provide input to or change settings on the vehicle, such as to climate control systems, GPS systems, and entertainment systems. More specifically, in motor vehicles, to minimize distraction during operation of the vehicle, haptic feedback systems provide the user with a touch feedback allowing the user to confirm that the desired input was properly entered and received by the vehicle while allowing the user to stay visually focused where needed during operation of the vehicle. 
         [0005]    One type of haptic effect can be generated from a haptic effect driver that is a linear actuator. One problem with haptic effect drivers in particular haptic systems that have panel style input surfaces actuated in a single degree of freedom is that the haptic feedback driver providing the haptic motion to the haptic or interface surface may be damaged when forces are applied in directions other than along the axis of the haptic feedback motion. As interface surfaces have increased in size, such as large touch screen displays, and particularly, those haptic feedback systems integrated into moving vehicles, the potential for off-axis forces being applied to the haptic feedback driver has increased. There are also many areas in a vehicle that may be subject to impact or contact due to shifting loads, operator movements or passenger movements in getting in and out of the vehicle. In summary, the concern is that any applied off-axis force may damage the haptic feedback driver and prevent it from operating properly. 
         [0006]    To address off-axis forces, some manufacturers have attempted to constrain motion of the interface surface through slides or other devices. These devices tend to be heavy, increase the friction and thereby the force required to move the interface surface as well as, in some instances, is susceptible to reduced operational performance due to dust or other contaminants over time. Any increase in required force to move the haptic surface or interface surface requires a more robust and larger haptic feedback driver which increases the cost of the system. In addition, most attempts to constrain motion of the interface surface results in additional material costs and additional assembly costs. Furthermore, it is important that the haptic feedback surface is not affected by environmental contaminants such as dirt, dust or even sticky solutions such as soda or juice being spilled on it as commonly can happen with many devices. The effect of environmental contaminants in these haptic systems is that the longevity of the haptic feedback driver or the ability of the haptic feedback driver to provide sufficient haptic motion to interface surface may be reduced or eliminated, primarily due to failure of the devices used to constrain motion. 
         [0007]    In addition, the assembly and attachment of a haptic surface to a base is complex and the system allowing haptic motion is expensive and bulky. They also can be difficult to assemble. 
         [0008]    Therefore, a need exists for a simple, easy to assembly, lightweight, low-cost, robust, and reliable haptic feedback system capable of constraining movement of an interface surface to movement that is substantially aligned to the axis of movement of the haptic feedback driver. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention is directed to a robust and compact haptic feedback system, more specifically, a haptic system that economically and reliably constrains movement of the interface surface to a single axis of motion to minimize potential for damage to a haptic feedback driver and more specifically, to a compliant mounting apparatus or member for haptic feedback systems that is capable of constraining motion of a haptic interface or interface surface in a single axis of movement. 
         [0010]    The present invention uses a series of beams or compliant members that extend between the interface surface and the base or the mounting surface of the haptics drive assembly. These compliant members generally fill two requirements. The first requirement is to attach the rear haptics assembly to the class-A interface surface, giving the class-A surface rigidity to keep it from being damaged during operation and typical use and abuse. The second function is to generally limit movement in a single degree of freedom so that haptic drivers can easily create a displacement on the class-A interface surface giving the user touching the surface acknowledgement that function has been actuated. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The present invention will become more fully understood from the detailed description given here below, the appended claims, and the accompanying drawings in which: 
           [0012]      FIG. 1  is a schematic side view of an exemplary haptic system; 
           [0013]      FIG. 2  is a perspective view of an exemplary haptic system; 
           [0014]      FIG. 3  is a perspective view of a compliant member showing movement in phantom lines; 
           [0015]      FIG. 4  is a side view of the compliant member showing movement in phantom lines; and 
           [0016]      FIG. 5  is an isometric view of a compliant member without the specific mounting on the ends to mount with the panel and base. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0017]    The present invention is directed to a haptic feedback system such as the exemplary haptic system  10  illustrated in  FIG. 1 . The haptic system  10  may be generally formed in any size, shape, or configuration and implemented in any desired device or any configuration within a device. The haptic system  10  is particularly applicable to devices having large input areas or interfaces. The haptic system  10  generally includes a rigid base  12  coupled to an interface surface or haptic surface  20  with a compliant member  30  therebetween. The compliant member  30  is configured to have significantly more flexibility along a single axis to provide desired haptic feedback through a flexibility difference due to a thin wall configuration in the direction of haptic motion. A haptic feedback driver  50  moves the interface surface  20  relative to the rigid base  12  thereby providing haptic feedback along a single axis of movement and the compliant member  30  constrains applied forces and movement of the interface surface to the single axis of movement. 
         [0018]    Depending on the desired functions, types of interfaces and configurations, as well as the type of device in which the haptic feedback system is incorporated, the size, shape, style, and configuration of the haptic feedback system  10  may vary widely. The rigid base  12  may vary in size, shape, and configuration and depend on the type of device in which the haptic feedback system  10  is incorporated. For example, the rigid base  12  may be formed separately as illustrated in  FIG. 2  or be formed as part of the frame or housing of the device (not illustrated). Similarly, the circuit boards  14  may have any desired size, shape, and configuration and instead of the single circuit board shown in  FIG. 1  may include multiple circuit boards, or in some embodiments, the related circuit boards may be located remotely from the interface surface  20 . 
         [0019]    The haptic feedback driver  50  is coupled to the rigid base  12 , or another fixed object, and haptic feedback driver  50  may be selected from a variety of devices capable of providing feedback. The driver  50  is generally illustrated in  FIG. 2  as a solenoid. As further illustrated in  FIG. 2 , the haptic feedback driver  50  includes an exemplary rigid attachment  52  which attaches the driver  50  to the base  12 . As further illustrated in  FIG. 2 , a shaft  58  extends from the driver  50  to be coupled to or attached to an interface attachment  54  which is connected or coupled to the interface surface  20 . Of course, any known method of connecting the haptic feedback driver between the base  12  and interface surface  20  such as to move the interface surface  20  along an axis of motion relative to the base  12  may be used. 
         [0020]    The interface surface  20  may be formed in a variety of styles and configurations. The interface surface  20  as illustrated in  FIG. 2  as input surface having touch screen (or surface) interface  60 . The touch screen interface  60  may include a variety of configurations, displays, and configurable options as desired. Of course, the touch screen interface  60  may also include touch screen buttons  62  such as virtual buttons that are shown on the screen that when touched haptic feedback movement of the interface surface  60  is provided. The touch screen interface  60  may also be connected with the circuit board  14  and various other controllers or processors  66  via the flex circuit  64  as illustrated in  FIG. 2 . 
         [0021]    In the present invention, the interface surface  20  is generally coupled to the base  12  with only a compliant member  30  or multiple compliant members  30 . The number of compliant members  30  used may vary depending on the size and design requirements of the interface surface  20 . As illustrated in  FIG. 2 , the interface surface  20  is shown being coupled to the rigid base  12  with two compliant members  30  which of course could be reduced to a single compliant member or include additional compliant members. It is important that the compliant members  30  are arranged such that they allow uniform movement in a single axis while constraining motion along substantially different axes. For example, if the compliant members  30  are not aligned with each other or substantially parallel to allow movement along the same axis and substantially perpendicular to the longitudinal axis of the compliant members, no movement of the interface surface  20  would be accomplished by the haptic driver  50 . The compliant member  30  may be coupled to the base  12  and the interface surface  20  by any desirable method including adhesive, mechanical fixtures, or other devices. The compliant member  30  is better illustrated in  FIGS. 3 and 4  which also show motion of the compliant member  30  along the direction of haptic feedback by arrow  22 . The motion of the compliant member  30  to allow directional movement along a single axis is illustrated with the phantom lines showing the flexing of the compliant member. The compliant members  30  generally are designed significantly thinner in the direction of motion as compared to the direction orthogonal to intended motion. This allows the compliant member to easily provide direction in a single axis while constraining movement in other axes cheaply and efficiently, the use of a compliant member also is easy to assemble and eliminates a variety of ports form traditional haptic systems. 
         [0022]    The compliant member is generally formed from a material such as steel or plastic but any material may work so long as it constrains the movement of the interface surface  20  as discussed above yet allowing for the proper compliance in the direction of desired movement of the interface surface  20 . The specific dimensions of the compliant member should be calculated based on the specific needs of the system being designed. But in the exemplary embodiment, the compliant member is formed from steel and generally has a cross-sectional thickness  89  of at least 2 times smaller than the longitudinal extent  88 . More specifically, the compliant member  30  generally has a large longitudinal extent  88  as compared to the lateral extent  89  such that the longitudinal extent  88  is typically at least 10 times longer than the lateral extent  89 . The height of the device  32  of the complaint member  30  may further be taken into account to allow the desired type of motion. More specifically, as the height  32  increases, the first end  31  rigidly affixed to the base  12  and the second end  33  affixed to the interface surface  20  may move relative to each other when driven by the haptic feedback driver  50  in increasing distances. This flexing motion even though in small increments allows the interface surface to provide the desired haptic feedback motion. The motion is illustrated as phantom lines  38  in  FIG. 3 . 
         [0023]    The foregoing discussion discloses and describes an exemplary embodiment of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims.