Abstract:
An operating element having a first control element that is rotatable about a first axis, and having at least one second control element that is rotatable about a second axis and that does not coincide with the first axis. The operating element may include apparatuses, arrangements or structures to influence the torque required to rotate at least one of the control elements. An operating device having an operating element has a controller to influence the torque required to rotate at least one of the control elements as a function of the context. The operating element and the operating device permit a good haptic feedback and/or user guidance in adjusting a parameter or in scrolling through a menu, so that visual contact with the operating element or a pointer moved with the operating element in a menu is not necessary.

Description:
BACKGROUND INFORMATION 
     The present invention relates to an operating element according to the definition of the species of the independent patent claim. 
     For personal computers, operating devices are known which have a spherical operating element, e.g., in the form of a computer mouse or a trackball, the latter preferably in portable personal computers. These devices are mostly used for two-dimensional input, e.g., for controlling the position of a pointer within a two-dimensional menu displayed on a computer monitor screen. The spherical operating element in such a known operating device is usually supported so that any translatory movement of the ball within the casing surrounding it is essentially suppressed. 
     In addition, International Patent Application WO-A 98/54670 describes an operating device having a spherical operating element in the form of a lockable trackball, the spherical operating element described there having at its surface trough-like recesses in which the catch elements engage. For the user, this permits improved haptic feedback regarding the extent of adjustment of the parameter adjusted with the spherical operating element. Visual control of the parameter to be adjusted can thus be eliminated under some circumstances. The device described here is therefore especially suitable,for use in such devices in which visual control of the parameters to be adjusted is difficult or impossible. 
     Finally, one-dimensional operating elements, e.g., in the form of rotary potentiometers or rotary increment encoders, which can rotate about an axis of rotation and permit an adjustment of one parameter, are also known. Various parameters to be adjusted can be assigned to such an operating element, e.g., through function keys. 
     One-dimensional rotary encoders having a positional memory fixedly predetermined by a locating spring and corresponding locating marks constitute another known embodiment of such one-dimensional operating elements. 
     ADVANTAGES OF THE INVENTION 
     The operating element according to the present invention having the features of the independent patent claim, namely an operating element having a first control element that can rotate about a first axis, wherein at least one second control element can rotate about a second axis which does not coincide with the first axis, has the advantage that two parameters can be adjusted independently of one another by using a single operating element. This permits, for example, control of a pointer in a two-dimensional menu, whereby in contrast with a single spherical operating element as a two-dimensional operating element, inadvertent adjustment in an unwanted dimension, e.g., as a result of vibration or a faulty optical feedback, is prevented by having only one dimension assigned to each control element of the operating element. 
     An especially advantageous embodiment of the operating element according to the present invention is characterized by the fact that the second control element has a rotationally symmetrical design and the at least two control elements are arranged so that the second control element surrounds the first control element at least in part. This has the advantage that the user can locate the additional control element(s) without any complicated searching through a slight translatory movement of the hand operating the element, even without direct visual contact with the operating element, based on the knowledge of the location of a first control element of the operating element. 
     Structuring of the surface of at least one of the control elements is especially advantageous because on the one hand the grip of the respective control element can be increased in this way, while on the other hand the user can be given a haptically mediated impression of the possible rotational degrees of freedom of the respective control element. 
     It is also advantageous to provide means for influencing the torque required to rotate at least one of the control elements of the operating element. In this way, the user can be provided with haptic feedback of the prevailing value of the parameter to be adjusted e.g., in adjustment of a parameter by way of the operating element, or he can be notified that he has arrived at an end of a value range of the parameter to be adjusted. 
     The latter case, i.e., haptic mediation of an impression through the dimension of a parameter setting, is possible in particular if a torque characteristic is generated via the means for influencing the torque required for rotation of at least one control element, thereby achieving engagement of the control element. 
     It is also advantageous that the spacings of the locating marks are not fixed in the case of an operating element according to the present invention, in contrast with the mechanical option mentioned in the preamble, but instead they can be varied as a function of the context, for example. Thus, when the operating element according to the present invention is used as a volume controller for a car radio, for example, a large number of locating marks can be distributed over a revolution of the operating element, which makes it possible to cover the entire volume range with a single revolution with a sufficiently high resolution. On the other hand, when using the operating element as a source switch for a car radio, for example, only a few locating marks, each being assigned to one audio source, could be distributed over one revolution of the operating element, thus yielding the conventional haptics for home audio systems, for example, with which the user is familiar. 
    
    
     DRAWINGS 
     Embodiments of the present invention are illustrated in the figures and explained in greater detail below. 
     They show 
     FIG. 1 a block diagram of an operating device having an operating element according to the present invention, 
     FIGS. 1A and 1B alternative embodiments of the operating element, 
     FIG. 2A a coding disk as part of a transformer, 
     FIG. 2B the time characteristic of pulse-shaped signals generated by the transformer as a result of rotation of one of the control elements of the operating element and 
     FIG. 3 an example of a menu having the respective torque characteristics which are imposed on the control elements of the operating element. 
    
    
     DESCRIPTION OF EMBODIMENTS 
     FIG. 1 shows a schematic diagram of an operating device  100  having an embodiment of an operating element  110  according to the present invention. Operating element  110  includes a first and a second control element  112  and  114 , first and second control elements  112  and  114  each being rotatable about their respective axis of rotation. First control element  112  is therefore mounted on a first axle  122 , and second control element  114  is mounted on a second axle, the axles being in turn mounted so they can rotate in bearings  126 . The axes of rotation of both control elements  112  and  114  thus coincide with the two axles on which they are arranged. 
     Bearings  126  are designed as simple friction bearings in the present embodiment, but they may also be implemented in the form of ball bearings, roller bearings or comparable bearings in a known manner. 
     First and second axles  122  and  124 , at the same time also being the axes of rotation of first and second control elements  112  and  114 , are exactly or at least approximately perpendicular to one another in the embodiment illustrated in FIG.  1 . However, a different arrangement of the at least two rotational axes  122  and  124  of the at least two control elements  112  and  114  in relation to one another is fundamentally also possible. 
     In the embodiment illustrated in FIG. 1, first control element  112  is designed in the form of a sphere, and second control element  114  is designed in the form of a hemisphere partially surrounding first control element  112 . In this way, the two control elements form an essentially spherical operating element  110  having a total of two rotational degrees of freedom, with user guidance already being provided due to the assignment of certain areas of operating element  110  (the upper hemisphere and the lower hemisphere  114  in FIG. 1) to different axes of rotation. 
     The surfaces of both control elements  112  and  114  are structured, each having a ribbing  113  and  115  on its surface in the embodiment illustrated in FIG.  1 . This ribbing is oriented in horizontal direction in first control element  112  and vertically in second control element  114 . It is used to impart haptic information to the user by way of the possible rotational degree of freedom of the respective control element. In addition, this surface structuring also increases the good grip of respective control element  112  or  114 . 
     According to an advantageous refinement of an operating element  110  according to the present invention, means  150 ,  160  are provided for influencing the torque required to rotate at least one of control elements  112  and  114 . In the present embodiment, they are designed in the form of actuators which can produce, for example, both a passive engagement of one or both control elements  112  and  114  at virtual locating marks produced by influencing means  150  and  160  as a function of the context as well as active jumping of one or both control elements  112  and  114  after deflection from one virtual resting position into the next resting position. 
     First gear wheels  156  and  166  are arranged on axles  122  and  124 , respectively, assigned to both control elements  112  and  114 , these gear wheels in turn meshing with other gear wheels  154  and  164  arranged on shafts of a first and a second motor  152  and  162 . First and second motors  152  and  162  together with gear wheels  154  and  156 , and  164  and  166 , respectively, arranged on axles  122  and  124  as well as motor shafts are the actuators or means  150 ,  160  for influencing the torque required to rotate control elements  112  and  114 , respectively. 
     Operating element  110  described previously together with its two control elements  112  and  114  is part of an operating device  100 . 
     In addition to actual operating element  110 , it also includes an analyzer for determining the extent of, in this case, rotation of control elements  112  and  114 . Therefore, a first transformer  130  is provided for first control element  112  and a second transformer  140  is provided for second control element  114  to determine the extent and the direction of rotation of respective control element  112  and  114  and to produce a signal indicating the extent and direction of rotation. 
     Transformers  130  and  140  in the present embodiment each include a pair of photoemitters  135  and  136  arranged side by side in parallel with respective shaft  122  and  124 . Arranged opposite photoemitters  135  and  136  is a pair of photodetectors  137  and  138 , so that first photoemitter  135  and first photodetector  137  as well as second photoemitter  136  and second photodetector  138  each form a photoelectric barrier. A coding disk  132  and  142 , respectively, coupled axially to shafts  122  and  124 , respectively, is arranged in the interspace between photoemitters  135 ,  136  and photodetectors  137 ,  138  of each transformer  130 ,  140 . Each coding disk  132 ,  142  is provided with a plurality of radially arranged slots  133 , so that a beam of light produced by one photoemitter  135 ,  136  and directed at corresponding facing photodetector  137 ,  138  is alternately interrupted or allowed to pass with the rotation of the respective control element and thus the respective coding disk  132 ,  142 . 
     Each coding disk  132 ,  142  interrupts in each case two beams of light emitted by photoemitters  137  and  138 . The distances between slots  133  in coding disks  132  and  142  in relation to the distance between photoemitters  137  and  138  and photodetectors  135  and  136  is such that when the beam of light of photoemitter  137  is allowed to pass completely through a slot  133 , the beam of light emitted by photoemitter  138  is partially blocked. 
     The interruptions in the beam of light due to a rotation of a coding disk  132  or  142  are detected by photodetectors  135 ,  136 , thus producing signals in the form of pulses. 
     FIG. 2B shows the time characteristic of these pulse-shaped signals. A first signal  170  is generated by first photodetector  135 , and a second signal  171  by second photodetector  136 . At time  172  indicated in FIG. 2A, first signal  170  has its maximum intensity corresponding to the full passage of the beam of light of first photoemitter  137 , while second signal  171  lags behind the first because the beam of light of second photoemitter  138  is allowed to pass through only partially. The number of pulses is a measure of the rotation of respective coding disk  132  or  142 , the sequence or chronological location of the pulses of both signals  170 ,  171  to one another permitting a determination regarding the direction of rotation of coding disk  132  or  142  and thus of control element  112 ,  114  assigned accordingly. 
     It is essential here that the effect described does not occur when the pulses within both signals  170 ,  171  occur simultaneously or at equal intervals from one another. Then it is no longer possible to detect the direction. 
     Output signals of transformers  130  and  140  are sent to an analyzer and control circuit  180 . 
     Analyzer and control circuit  180  includes a memory (not shown separately in FIG. 1) in which torque characteristics are stored. They are allocated to the respective control element as a function of the respective context, i.e. a menu called up currently or run through by one of control elements  112  or  114 . 
     FIG. 3 shows as an example such a menu  200  as already known for office applications in widely used computer programs, for example. It includes a one-dimensional menu  270  having contents  271 ,  272  and  273  presented horizontally on a display instrument (not shown in FIG.  1 ). In the present example of FIG. 3, for example, the contents of this menu  270  might include selection of a radio transmitter to be received in a radio receiver ( 271 ), adjustment of the playback volume of the radio receiver ( 272 ) and adjustment of the sound by using a sound equalizer ( 273 ) such as that known essentially from radio receiver technology. 
     Selection of one of the contents  271  through  273  of menu  270  is made by rotating second control element  114 , which can rotate about the perpendicular axis of rotation in the plane of the page. The torque imposed on second control element  114  by actuator  160  assigned by controller  180  must be overcome to to rotate second control element  114 . To illustrate the resulting locating effects, the figure shows curve  280  of the absolute value of the torque. Notched positions of the second control element at its angles of rotation of 0, 90 and 180 degrees are assigned to selectable contents  271  through  273 . A comparatively high torque must be overcome to move the control element or a pointer controlled by control element  114  from one content  271  to  273  within the menu. However, once it has been overcome, the control element automatically jumps to next content  272  of the menu beyond a certain angular position, e.g., at approximately 45 degrees, and then engages there. This is illustrated by the curve labeled  280 . 
     If second control element  114  is rotated beyond an angle of 180 degrees or 0 degrees, depending on whether the direction of rotation is positive or negative, and thus the respective pointer is pushed beyond contents  273  or  271 , the torque required to rotate control element  112  increases to a high value, thus giving haptic feedback to the user that he is approaching the end of the current menu. If control element  112  is nevertheless moved further, the pointer can jump from last entry  273  in menu  270  back to first entry  271  or from first entry  271  to last entry  273 , depending on the direction of rotation of control element  112 . 
     For example, if item  271  has been selected, i.e., selecting a radio transmitter from a stored list of radio transmitters, for example, the display unit will then show another menu  210 , now arranged vertically, having selectable radio transmitters  211 ,  212 ,  213 ,  214 ,  215 ,  216 ,  217 ,  218  and  219 . At the right of this is shown curve  220  of torque  220  required to rotate first control element  112  to run through menu  210 . This is in turn characterized in that after deflection of control element  112  from a notched position corresponding to a transmitter  213  in menu  210 , for example, control element  112  and the cursor moved by it automatically jump to next adjacent radio transmitter  214  or  212 , depending on the direction of rotation, in menu  210  and engage there. Curve  225  of the absolute value of the torque illustrates this once again. 
     If second list item  272  of menu  270 , i.e., the volume setting, has been selected, then another menu  230  is displayed vertically on the display unit, containing a plurality of values  231 ,  232 ,  233 ,  234 ,  235 ,  236 ,  237 ,  238  and  239  corresponding to volume values. Controller  180  also assigns a torque curve, whose absolute value  240  is plotted over the angular position of second control element  114 , to the volume setting. It has a slightly wavy curve over the angular range from 0 to 270 degrees of control element  114  assigned to entire control range  231  to  239 , thus resulting in a slight notching effect when passing through the range. The user thus receives haptic feedback regarding the extent of the parameter adjustment, namely a volume adjustment here, made by operating element  110 . 
     Finally, if third item  273  of menu  270 , namely the sound setting, has been selected, then in turn a menu  250  which extends vertically is displayed on the display unit by controller  180 . It extends from a very bass-heavy sound  251  over a setting  252  representing a balanced, neutral sound to a strongly treble sound  253 . Curve  260  assigned to the first control element by controller  180  for adjusting the sound resembles that for the volume adjustment, but it has a distinctly perceptible locating mark in the area of neutral setting  252 . 
     The preceding discussion illustrates the fact that an individual assignment of a certain torque characteristic to one of two control elements  112  or  114  of operating element  110  as a function of a parameter to be adjusted is possible. The absolute value of the torque required to rotate one of the control elements and the distribution of locating marks on the periphery or a revolution of a control element can be predetermined as a function of the context. Thus, for example, it is equally possible to distribute a plurality of volume values and thus locating marks, i.e., a high resolution of the volume with a broad volume range and thus a wide adjustment range over, for example, three-quarters of a revolution of a control element as it is to distribute, for example, just three entries  271  through  273  of menu  270  over half of a revolution of second control element  114 . 
     Likewise, however, it is also possible to assign a smooth torque curve without locating marks or even a constant torque to a certain parameter to be adjusted. In this way, for example, the usual haptics for a traditional volume potentiometer may also be assigned to a volume adjustment for an audio system. 
     In addition, it is also possible to adjust the torques required to rotate both control elements  112  and  114  of operating element  110  independently of one another. In particular, it is also possible, for example, to completely block one of the two control elements for the case when only a one-dimensional menu is available and thus to give the user haptic feedback indicating that this is only a one-dimensional menu. Thus, for example, in the case of menu  270 , first control element  112  can be blocked completely. In this way, the user receives the additional information that menu  270 , which is in a one-dimensional form, evidently extends in the horizontal direction but not in the vertical direction. Thus, haptic user guidance is also possible by suitable action on control elements  112  and  114  of operating element  110 . 
     It is also within the scope of the present invention for control elements  112  and  114  of operating element  110  not to be designed essentially spherically or hemispherically in deviation from the illustration in FIG.  110 . For example, the control elements may also be designed in the form of a wheel  117  arranged on second axle  124  and a roller arranged on first axle  122 , as illustrated in FIG.  1 B. Likewise, the control elements of the operating element may also be designed, for example, in the form of an ellipsoid (first control element  118 ) and a semi-ellipsoid (second control element  119 ).