Multi-directional actuating module
10921895 ยท 2021-02-16
Assignee
Inventors
- Hyeong Jun Kim (Seoul, KR)
- Jong Hun Lee (Seoul, KR)
- Nam Seok Kim (Seoul, KR)
- Myung Sun Park (Seoul, KR)
- Ji Goo Kang (Seoul, KR)
Cpc classification
G06F3/0338
PHYSICS
H02K33/00
ELECTRICITY
H02K33/16
ELECTRICITY
B06B1/045
PERFORMING OPERATIONS; TRANSPORTING
H02K33/02
ELECTRICITY
G06F3/016
PHYSICS
International classification
H02K33/16
ELECTRICITY
B06B1/04
PERFORMING OPERATIONS; TRANSPORTING
H02K33/02
ELECTRICITY
H02K33/00
ELECTRICITY
Abstract
One embodiment provides a multi-directional actuating module capable of moving in various directions and capable of delivering various tactile senses such as knocking or rubbing as well as vibration by controlling at least one of the intensity, direction or frequency of a magnetic field generation unit. Further, the multidirectional actuating module according to one embodiment may comprise: a moving body capable of moving in at least two or more axial directions by means of an external magnetic field; a support for supporting the moving body so as to be movable; and at least two or more magnetic field generation units which are in the form of a coil to generate the magnetic field.
Claims
1. A haptic device comprising: a magnetic field generating module configured to generate at least two distinct magnetic fields; a moving body including magnetic particles and configured to move in at least two axial directions by the at least two distinct magnetic fields generated by the magnetic field generating module; a support configured to support the moving body to be movable; a connecting body configured to transfer at least one of a vibration, a rotation, and a translation of the moving body; a transmitter configured to transmit a tactile signal to a user by moving together with the moving body; and a controller configured to provide at least one tactile sense which includes vibration, tapping, rubbing or twisting by transmitting a signal to the magnetic field generating module.
2. The haptic device of claim 1, wherein the at least two distinct magnetic fields comprise a first magnetic field and a second magnetic field, and wherein the first and second magnetic fields are in the same direction to allow upward and downward movement of the moving body relative to the magnetic field generating module.
3. The haptic device of claim 1, wherein at least two distinct magnetic fields comprise a first magnetic field and a second magnetic field, and wherein the first and second magnetic fields are in the opposite directions to allow side-to-side movement of the moving body relative to the magnetic field generating module.
4. The haptic device of claim 1, wherein the moving body vibrates when an alternating current (AC) is applied to the magnetic field generating module.
5. The haptic device of claim 1, wherein the moving body rotates or translates when a direct current (DC) current is applied to the magnetic field generating module.
6. The haptic device of claim 1, wherein the controller provides the at least one tactile sense by controlling at least one of a frequency, a direction or an intensity of current that is applied to the magnetic field generating module.
7. The haptic device of claim 1, wherein the support comprising: a support wall configured to encompass the moving body; and at least one connector configured to connect the support wall and the moving body and made of an elastic material.
8. The haptic device of claim 7, wherein the magnetic field generator is arranged above or below the moving body, and the at least one connector is disposed on a periphery of a side surface of the moving body.
9. The haptic device of claim 7, wherein the at least one connector comprises: a first connector disposed on the first side relative to the moving body; and a second connector disposed on the second side relative to the moving body.
Description
BRIEF DESCRIPTION OF DRAWINGS
(1) These and/or other aspects, features, and advantages of the invention will become apparent and more readily appreciated from the following description of example embodiments, taken in conjunction with the accompanying drawings.
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DETAILED DESCRIPTION
(12) Hereinafter, some example embodiments will be described in detail with reference to the accompanying drawings. Regarding the reference numerals assigned to the elements in the drawings, it should be noted that the same elements will be designated by the same reference numerals, wherever possible, even though they are shown in different drawings. Also, in the description of embodiments, detailed description of well-known related structures or functions will be omitted when it is deemed that such description will cause ambiguous interpretation of the present disclosure.
(13) In addition, terms such as first, second, A, B, (a), (b), and the like may be used herein to describe components. Each of these terminologies is not used to define an essence, order or sequence of a corresponding component but used merely to distinguish the corresponding component from other component(s). It should be noted that if it is described in the specification that one component is connected, coupled, or joined to another component, a third component may be connected, coupled, and joined between the first and second components, although the first component may be directly connected, coupled or joined to the second component.
(14) Unless otherwise defined, all terms, including technical and scientific terms, used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Terms, such as those defined in commonly used dictionaries, are to be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art, and are not to be interpreted in an idealized or overly formal sense unless expressly so defined herein.
(15)
(16) The haptic device 1 may include a magnetic field generating module 13 configured to generate a magnetic field, a moving body 11 configured to move by the magnetic field, a support 12 configured to support the moving body 11 to be movable, and a transmitter 30 configured to transmit a tactile signal by moving together with the moving body 11 when the moving body 11 moves. The transmitter 30 may be provided in a form of, for example, a display or a glove.
(17) Also, the haptic device 1 may include at least one connecting body 20 configured to connect the moving body 11 and the transmitter 30. The connecting body 20 may be provided in a form of, for example, a rod. The connecting body 20 may function as a medium to transfer movements such as a vibration, a rotation, and/or a translation (, hereinafter, also referred to as motion collectively) of the moving body 11.
(18) The moving body 11 may perform various motions as further discussed below. In an example, by a magnetic field generated when an alternating (AC) current is applied to a magnetic field generator of the magnetic field generating module 13, the moving body 11 may repetitively move in a vertical direction, which may be understood as vibration. In another example, by a direct (DC) current consistently applied to a magnetic field generator of the magnetic field generating module 13, an angle of the moving body 11 relative to the magnetic field generating module 13 may be changed or a position of the moving body 11 relative to the magnetic field generating module 13 may be changed, which may be understood as rotation and translation, respectively. The movements of the vibration, the rotation, and the translation may occur simultaneously. Such movements may also be referred to as a motion.
(19)
(20) The actuating module 10 may include the moving body 11 configured to move by an external magnetic field, the support 12 configured to support the moving body 11 to be movable, and the magnetic field generating module 13 provided in a form of a coil to generate a magnetic field.
(21) The support 12 may include a support wall 122 configured to encompass the moving body 11, and at least one connector 121 configured to connect the support wall 122 and the moving body 11 and formed of a deformable material. The connector 121 may have, for example, an arm shape and an elasticity to restrict a movable range of the moving body 11 and provide a restoring force.
(22) For example, the connector 121 may include a plurality of parallel bars in parallel to a longitudinal direction of each side of the moving body 11 and at least one connecting bar connecting the plurality of parallel bars. The plurality of parallel bars may be greater in length than the at least one connecting bar. In other words, lengths of the plurality of parallel bars may be greater than distances between the parallel bars. The connector 121 may have a shape that is bent a plurality of times as shown in the figure. One end portion of the connector 121 may be connected to one end portion of each side of the moving body 11 having a quadrangular plate shape. In the above-mentioned shape, a direction of a force transmitted through the connector 121 may be deviated from a center of gravity of the moving body 11 such that the moving body 11 performs a rotation motion and a translation motion, which may provide a tactile sense such as a sense of twisting. The connectors 121 may be arranged in point symmetry with respect to a center of the moving body 11.
(23) The magnetic field generating module 13 may be disposed above or below the moving body 11. The connector 121 may be arranged on a periphery of a side surface of the moving body 11.
(24) The moving body 11 may be formed of a material to react with an external magnetic field and to be magnetically polarized. The connector 121 may be formed of a matrix material having the elasticity.
(25) The magnetic field generating module 13 may include a first magnetic field generator 131 and a second magnetic field generator 132, each provided in a form of a coil, and a case 133 configured to fix positions of the first magnetic field generator 131 and the second magnetic field generator 132 and enclose the first magnetic field generator 131 and the second magnetic field generator 132. Magnetic properties of the first magnetic field generator 131 and the second magnetic field generator 132 may be the same or different.
(26) The moving body 11 may be formed in various shapes based on a shape of an actuator or a type of tactile sense to be transmitted. Also, the moving body 11 may be supported by at least two connectors 121.
(27) The moving body 11 may include, for example, metal particles such as ion, ferrite, cobalt, samarium, strontium, barium, aluminum, nickel, and neodymium in nano or micron units, a polymer, plastic, or rubber material such as silicone, polyurethane, nitrile, polyethylene, and polyethylene, and combinations thereof.
(28) The moving body 11 may be magnetized to achieve a maximum magnetic force. A magnetization may be performed in a one direction based on a coil or to achieve two poles on one face, multiple poles on one face, or multiple poles on double faces.
(29) In
(30) A surface of the moving body 11 may be formed with a soft magnetic material such as soft iron, silicon steel, and quartz to effectively use a magnetic force. The surface of the moving body 11 may also be formed with a mixed material of soft magnetic material powder and a polymer, plastic, or rubber material such as silicone, polyurethane, nitrile, polyethylene, and polyethylene.
(31) The connector 121 including the matrix material may change a shape in response to a motion including the vibration and the like of the moving body 11. Also, the connector 121 may increase a modulus of elasticity to reach at least a predetermined level, thereby maximizing the restoring force.
(32) At least two connectors 121 may be provided to efficiently support the moving body 11 moving in a multi-direction based on moving directions of the moving body 11. The at least two connectors 121 may include a first connector disposed on a first side relative to the moving body 11 and a second connector disposed on a second side relative to the moving body 11.
(33) A shape of the connector 121 may be at least one selected from a group including a straight line, a rhombus, an arm, and a combination thereof.
(34) In an example, the connector 121 may include a rubber, a polymer material, or a silicone material. To change the modulus of elasticity, the connector 121 may include an additive agent such as an antifoaming agent, a plasticizer, a reinforcing filler, and a softener.
(35) In another example, the connector 121 may include a rubber, a polymer material, or a silicone material. To change the modulus of elasticity, a process such as vacuum defoaming, hot curing or foaming may be performed on the connector 121.
(36) The magnetic field generators 131 and 132 may be arranged in at least one of an upper side or a lower side of the moving body 11 and may be in a position or a shape corresponding to the moving body. Also, the magnetic field generators 131 and 132 may have the same or different magnetic properties in relation to the moving body 11 at portions in contact with the moving body 11.
(37) A polygonal plane coil having, for example, a circle, ellipse or rectangle shape, or a solenoid coil may be used as the magnetic field generators 131 and 132. Center holes of the magnetic field generators 131 and 132 may each be hollow or include a soft magnetic core formed of a material such as soft iron, steel, and stone.
(38) The magnetic field generators 131 and 132 may be provided as a plurality of magnetic field generators based on directions in which the moving body 11 is to move. The magnetic field generators 131 and 132 may include the first magnetic field generator 131 disposed on a first side and the second magnetic field generator 132 disposed on a second side opposite to the first side.
(39) The magnetic field generators 131 and 132 may have the same or different magnetic properties, and a DC or AC current may be applied thereto.
(40) The magnetic field generating module 13 may adjust a space between magnetic field generating modules, an intensity of magnetic field, and a direction of current applied to each magnetic field generating module based on a number of actuating directions, a performance, and a design of the actuating module 10.
(41) Also, a degree of a motion including, for example, the vibration of the moving body 11 may be controlled based on a frequency, an intensity, a direction of current applied to a coil, a coil shape, a space between coils, an elasticity of a connector, a weight of the moving body 11 or a combination thereof.
(42) Referring to
(43)
(44) To measure an effect exerted on an intensity of a horizontal vibrating force applied to the moving body 11 based on a space between the magnetic field generators 131 and 132, a horizontal vibrating force may be measured by slightly increasing a space between the magnetic field generators 131 and 132.
(45) As shown in the graph, when the magnetic field generators 131 and 132 are in contact with each other, the space between the magnetic field generators 131 and 132 may be 50% of a length of one side of the moving body 11 laid in a direction traversing centers of the magnetic field generators 131 and 132. In this example, the horizontal vibrating force applied to the moving body 11 based on the magnetic field generators 131 and 132 may increase, and then decrease.
(46) Also, it can be known from the graph that a maximum horizontal vibrating force is obtained when a distance between the centers of the magnetic field generators 131 and 132 ranges between 90% and 110% of the one side of the moving body 11 laid in the direction traversing the centers of the magnetic field generators 131 and 132.
(47)
(48) As illustrated in
(49)
(50) A horizontal vibrating force may be measured by changing a shape of the magnetic field generators 131 and 132 to circular, elliptical, and rectangular shapes. To exclude effects of factors other than the shape of the magnetic field generators 131 and 132, each of the magnetic field generators 131 and 132 may be manufactured to have the same current and the same number of turns.
(51) As shown in the graph, a relatively high intensity of horizontal vibrating force may be obtained when the magnetic field generators 131 and 132 having the same current and the same number of turns is in the circular or elliptical shape.
(52) Hereinafter, a motion mechanism including the vibration and the like of the actuating module 10 will be described.
(53)
(54) Four connectors including the connector 121 may support the moving body 11 that is vertically polarized and magnetized. Two magnetic field generators, for example, the magnetic field generators 131 and 132 may be arranged below the moving body 11.
(55) The two magnetic field generators 131 and 132 may be configured to have the same magnetic properties. When an AC current is applied to the two magnetic field generators 131 and 132, an attractive force and a repulsive pulse may alternately generated between the moving body 11 and the magnetic field generators 131 and 132 due to the magnetic properties of the magnetic field generators 131 and 132.
(56) In this example, the moving body 11 may perform a to-and-fro motion between a first position toward which a relative distance from the magnetic field generators 131 and 132 increases due to the repulsive force and a second position toward which a relative distance from the magnetic field generators 131 and 132 decreases due to the attractive force.
(57) Also, in response to at least one of a frequency, a direction or an intensity of a magnetic field formed by the magnetic field generators 131 and 132 being controlled, at least one of a frequency or an intensity changing direction from the first position to the second position may be controlled, thereby generating a tactile signal of, for example, a vibration or a tapping.
(58)
(59) Similarly to a Z-axis directional motion, four connectors including the connector 121 may support the moving body 11 that is vertically polarized and magnetized. Also, the two magnetic field generators 131 and 132 may be arranged to be adjacent to a bottom of the moving body 11.
(60) Unlike the Z-axis directional motion, the two magnetic field generators 131 and 132 may be configured to have different magnetic properties, and an AC current may be applied to the two magnetic field generators 131 and 132.
(61) As illustrated in
(62) Thereafter, when opposite directional currents are applied to the two magnetic field generators 131 and 132, the first magnetic field generator 131 and the second magnetic field generator 132 may be reversed in magnetic property in a vicinity of the moving body 11.
(63) Accordingly, as illustrated in
(64) In the moving body 11, a motion of a direction from the first magnetic field generator 131 to the second magnetic field generator 132 may be switched to a motion of a direction from the second magnetic field generator 132 to the first magnetic field generator 131. When the switching is repeated, a to-and-fro motion of an X-axial direction may be implemented. For example, by applying the AC current to the first magnetic field generator 131 and the second magnetic field generator 132, the to-and-fro motion of the X-axial direction may be implemented.
(65) Also, in response to at least one of a frequency, a direction or an intensity of a magnetic field formed by the magnetic field generators 131 and 132 being controlled, at least one of a frequency or an intensity changing direction between a coil of the first magnetic field generator 131 and a coil of the second magnetic field generator 132 may be controlled, thereby generating a tactile signal of, for example, an X-axial directional vibration or tapping.
(66)
(67) Similarly to a 2-directional actuating module, four connectors including the connector 121 may support the moving body 11 that is vertically polarized and magnetized. Also, four magnetic field generators, for example, a first magnetic field generator 141, a second magnetic field generator 142, a third magnetic field generator 143, and a fourth magnetic field generator 144 may be arranged to be adjacent to a bottom of the moving body 11. The four magnetic field generators 141, 142, 143, and 144 may be configured as a magnetic field generator set 140.
(68) The magnetic field generator set 140 may include the first magnetic field generator 141, the second magnetic field generator 142, the third magnetic field generator 143, and the fourth magnetic field generator 144.
(69) The four magnetic field generators 141, 142, 143, and 144 may be arranged in a quadrangular form (as shown in
(70) In
(71) In
(72) The following description will be based on the quadrangular-form arrangement corresponding to
(73) Similarly to the aforementioned 2-directional actuating module, to allow the moving body 11 to move in the Z-axial direction, the four magnetic field generators 141, 142, 143, and 144 may be configured to have the same magnetic properties. When an AC current is applied to the magnetic field generators, an attractive force and a repulsive pulse may alternately generated between the four magnetic field generators 141, 142, 143, and 144 and the moving body 11 located adjacent thereto.
(74) When two magnetic field generators are used for the Z-axis directional motion, it is appropriate to use the first and third magnetic field generators or the second and fourth magnetic field generators 142 and 144 so as to be balanced.
(75) The moving body 11 may perform a to-and-fro motion between a first position toward which a relative distance from the magnetic field generator set 140 increases due to the repulsive force and a second position toward which a relative distance from the magnetic field generator set 140 decreases due to the attractive force.
(76) Also, in response to at least one of a frequency, a direction or an intensity of a magnetic field formed by from the magnetic field generator set 140 being controlled, at least one of a frequency or an intensity changing direction from the first position to the second position may be controlled, thereby generating a tactile signal of, for example, a vibration and a tapping.
(77) Hereinafter, a Z-axis directional partial motion of the moving body 11 will be described.
(78) The AC current may be applied to the first magnetic field generator 141. A DC current may be applied to the second, third, and fourth magnetic field generators 142, 143 and 144 such that the second, third, and fourth magnetic field generators 142, 143 and 144 have magnetic properties opposite to that of the moving body 11.
(79) In this example, when the AC current is applied to the first magnetic field generator 141, the attractive force and the repulsive pulse may alternately generated between the moving body 11 and the first magnetic field generator 141. Also, the attractive force may be continuously generated between the second, third, and fourth magnetic field generators 142, 143 and 144 and the moving body 11.
(80) Due to the attractive force relative to the second, third, and fourth magnetic field generators 142, 143 and 144, a distance between the moving body 11 and the first magnetic field generator may decrease. By the AC current applied to the first magnetic field generator, the attractive force and the repulsive force may be alternately generated in an area between the first magnetic field generator and a portion of the moving body 11 adjacent to the first magnetic field generator. Through this, the portion of the moving body 11 adjacent to the first magnetic field generator 141 may perform the to-and-fro motion in the Z-axial direction.
(81) When compared to the Z-axis directional motion in which the motion occurs in a center portion of the moving body 11 in the 2-directional actuating module, a partial vibrating sense may be provided from a vibration source biased to the first magnetic field generator in a diagonal direction.
(82) Similarly, the AC current may be applied to the second magnetic field generator 142 and the DC current may be applied to the first, third, and fourth magnetic field generators 141 143 and 144 such that to the first, third, and fourth magnetic field generators 141, 143 and 144 have a magnetic property opposite to that of the moving body 11. In this example, when the AC current is applied, the attractive force and the repulsive pulse may alternately generated between the second magnetic field generator 142 and a portion of the moving body 11 adjacent to between the second magnetic field generator 142. Also, the attractive force may be continuously generated with respect to the first, third, and fourth magnetic field generators 141, 143 and 144.
(83) Likewise, the Z-axis directional motion may occur in a desired portion of the moving body 11 when the AC current is applied to the third magnetic field generator 143 or the fourth magnetic field generator 144, and the DC current is applied to remaining magnetic field generators to have the magnetic property opposite to that of the moving body 11.
(84) Also, the Z-axis directional motion may occur in a desired portion of the moving body 11 when the AC current is applied to two neighboring magnetic field generators among a plurality of magnetic field generators, and the DC current is applied to remaining magnetic field generators to have the magnetic property opposite to that of the moving body 11.
(85) Hereinafter, the X-axis directional partial motion of the moving body 11 associated with the actuating modules 20 and 30 will be described with reference to
(86) When implementing the X-axis directional motion using magnetic field generators arranged as illustrated in
(87) The moving body 11 may receive the attractive force and the repulsive force from the first and second magnetic field generators 141 and 142 and receive the repulsive force and the attractive force from the third and fourth magnetic field generators 143 and 144, alternately. Through this, the moving body 11 may perform a motion in the X-axial direction which is a direction corresponding to a vector sum thereof.
(88) When magnetic field generators are arranged as illustrated in
(89) A specific motion mechanism may be the same as the mechanism of the X-axis directional motion in a first example embodiment except for a magnetic field generator to be used.
(90) Hereinafter, a Y-axis directional motion of the moving body 11 associated with the actuating modules 20 and 30 will be described with reference to
(91) When implementing the Y-axis directional motion using magnetic field generators arranged as illustrated in
(92) The moving body 11 may receive the attractive force and the repulsive force from the first and fourth magnetic field generators 141 and 144 and receive the repulsive force and the attractive force from the second and third magnetic field generators 142 and 143, alternately. Through this, the moving body 11 may perform a motion in a Y-axial direction which is a direction corresponding to a vector sum thereof.
(93) When implementing the Y-axis directional motion using magnetic field generators arranged as illustrated in
(94) A specific motion mechanism may be the same as the mechanism of the X-axis directional motion of the actuating module 10 including two magnetic field generators except for a number of magnetic field generators to be used.
(95) Hereinafter, a diagonal motion of the moving body 11 associated with the actuating modules 20 and 30 will be described with reference to
(96) In a coordinate system, to allow the moving body 11 to move in a Y=X line direction, the first magnetic field generator 141 and the third magnetic field generator 143 may be used based on the actuating module 30 of
(97) Specifically, when a current is applied to the first and third magnetic field generators 141 and 143 to have opposite magnetic properties, the attractive force may be generated between the first magnetic field generator 141 and the moving body 11 and the repulsive force may be generated between the third magnetic field generator 143 and the moving body 11.
(98) The moving body 11 may receive the attractive force from the first magnetic field generator 141 and receive the repulsive force from the third magnetic field generator 143, thereby moving in a direction corresponding to a vector sum thereof.
(99) Thereafter, the AC current may be applied to the four magnetic field generators 141, 142, 143, and 144. Thus, the magnetic properties of the magnetic field generators 141, 142, 143, and 144 may be changed at portions adjacent to the moving body 11.
(100) By the AC current applied to each of the magnetic field generators 141, 142, 143, and 144, the moving body 11 may repetitively perform the diagonal motion. Through this, a Y=X line directional motion of the moving body 11 may be implemented.
(101) Hereinafter, a Y=X line directional motion of the moving body 11 associated with the actuating modules 20 and 30 will be described with reference to
(102) In a coordinate system, to allow the moving body 11 to move in a Y=X line direction, the second magnetic field generator 142 and the fourth magnetic field generator 144 may be used based on the actuating module 30 of
(103) The Y=X line directional motion and the Y=X line directional motion may be implemented using the actuating module 20 of
(104) To implement the Y=X line directional motion, the first magnetic field generator 141 and the second magnetic field generator 142 may be provided as a pair, and the third magnetic field generator 143 and the fourth magnetic field generator 144 may be provided as a pair. A current may be applied to each of the pairs such that the corresponding magnetic field generators have the same magnetic property.
(105) Different pairs may need to be controlled to have opposite magnetic properties.
(106) In this example, the attractive force may be generated between the moving body 11 and the first and second magnetic field generators 141 and 142, and the repulsive force may be generated between the moving body 11 and the third and the fourth magnetic force generators 143 and 144.
(107) The moving body 11 may simultaneously receive the attractive force from the first and second magnetic field generators 141 and 142 and simultaneously receive the repulsive force from and the third and the fourth magnetic force generators 143 and 144, thereby moving in a direction corresponding to a vector sum thereof.
(108) Thereafter, the AC current may be applied to the four magnetic field generators 141, 142, 143, and 144. Thus, the magnetic properties of the magnetic field generators 141, 142, 143, and 144 may be changed at portions adjacent to the moving body 11.
(109) By the AC current applied to each of the magnetic field generators 141, 142, 143, and 144, the moving body 11 may repetitively perform the motion. Through this, the Y=X line directional motion may be implemented.
(110) Conversely, to implement the Y=X line directional motion, the first and fourth magnetic field generators 141 and 144 may be provided as a pair, and the second and third magnetic field generator 142 and 143 may be provided as a pair.
(111) To implement a motion of the multi-directional actuating module in an additional direction, a plurality of magnetic field generators may be arranged along a circumference of a virtual circle that shares a center with a center of an actuator. In this example, a number of the magnetic field generators may correspond to a number of directions in which the multi-directional actuating module is to move.
(112) Also, an external current may be applied to the magnetic field generators 131 and 132 in a form of, for example, a rectangular wave, a pulse wave, or a sine wave. Using different input waveforms, the actuating module may provide different tactile senses to a user.
(113) A number of example embodiments have been described above. Nevertheless, it should be understood that various modifications may be made to these example embodiments. For example, suitable results may be achieved if the described techniques are performed in a different order and/or if components in a described system, architecture, device, or circuit are combined in a different manner and/or replaced or supplemented by other components or their equivalents. Accordingly, other implementations are within the scope of the following claims.