Drum haptic feedback device steering unit and method

Abstract

A tactile feedback device (TFD) drum brake has a drum rotor that creates at least two gaps and at least four shear planes. A magnetically responsive (MR) material is disposed in the gaps. The TFD drum brake further has an upper magnetic seal and a lower magnetic seal to prevent the MR material from migrating out of the gaps. The drum rotor is thin and quickly saturates when a magnetic flux is created. When the drum rotor reaches saturation, a controllable torque is created. The controllable torque provides feedback to an operator of a vehicle in which the TFD drum brake is installed.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 63 / 092,046, filed on October 15, 2020, entitled “DRUM TACTILE FEEDBACK DEVICE STEERING UNIT AND METHOD”, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] This article generally covers the field of resistance torque generating devices and systems, such as brakes, locking devices, clutches, haptic feedback devices, resistance generating devices, motion control devices, etc. More specifically, this article relates to haptic feedback (TFD) drum brakes that use magnetically responsive (MR) materials to generate resistance torque. Background Technology

[0004] Existing magnetic response (MR) devices (such as disc rotor brakes and drum brakes) have a gap between the rotor and coil that creates a shear plane. Existing drum brakes do not have and cannot support more than two shear planes. Torque is limited by the size of the device and the available shear planes. Additionally, existing MR devices using MR materials require expensive seals to prevent MR material from migrating from the gap into the rest of the device. What is needed is a smaller MR drum that can provide greater torque than existing devices. Moreover, what is needed is an MR drum brake with improved seals to prevent MR material migration. Summary of the Invention

[0005] In one aspect, a haptic feedback device (TFD) drum brake is provided. The TFD drum brake includes a shaft, a drum rotor, a core, a pole ring, a magnetic response (MR) material, an upper magnetic seal, a lower magnetic seal, at least one sensor, and a housing encapsulating the aforementioned components. The shaft has a rotating disk rotatably connected thereto. The drum rotor is connected to the rotating disk. The core has an integrated coil radially inwardly positioned from the drum rotor, forming a first gap between the integrated coil and the drum rotor. The pole ring is radially outwardly fixedly positioned from the drum rotor, forming a second gap between the pole ring and the drum rotor. The MR material is disposed within the first and second gaps. The upper magnetic seal is positioned to prevent movement of the MR material from the second gap. The lower magnetic seal is positioned to prevent movement of the MR material from the first gap. The housing encapsulates the shaft, drum rotor, core, upper magnetic seal, and lower magnetic seal. The housing has a housing cover and a sensor housing fixed thereto. At least one sensor is capable of detecting rotation of the shaft.

[0006] In another aspect, a TFD drum brake is provided. The TFD drum brake includes a shaft, a drum rotor, a pole ring, a core, a rotating disk, an upper magnetic seal, a lower magnetic seal, MR material, at least one sensor, and a housing encapsulating the aforementioned components. The drum rotor has a first brake shear surface and a second brake shear surface, where the first brake shear surface is on a rotor inner surface (RIS) of the drum rotor and the second brake shear surface is on a rotor outer surface (ROS) of the drum rotor. The pole ring has a pole ring shear surface on a pole ring inner surface (PRIS) that is fixedly positioned and positioned opposite the ROS, where a second gap is positioned between the PRIS and the ROS. The core has an integrated coil. The core has a core shear surface on a core outer surface (COS) that is positioned opposite the RIS, where a first gap is positioned between the COS and the RIS. The rotating disk has an end, where the drum rotor is connected to the end and the rotating disk is rotatably connected to the shaft. The MR material is disposed within the first gap and the second gap. The housing includes a housing cover that is fixed to a housing wall at a housing top edge of the housing wall. The housing also includes a sensor housing that is fixed to the housing wall at a housing bottom edge of the housing wall. The upper magnetic seal is positioned to prevent movement of the MR material from the first gap through an upper void between the upper magnetic seal and the housing cover. The lower magnetic seal is positioned to prevent movement of the MR material from the second gap through a lower void between the lower magnetic seal and the core.

[0007] In another aspect, a method of providing haptic feedback using a TFD drum brake 10 is provided. The method includes generating torque with the TFD drum brake by energizing the integrated coil by applying current to it, magnetically saturating the drum rotor, and generating a resistive torque. The drum brake includes a housing that encapsulates a shaft, a drum rotor, a pole ring, a core, a rotating disk, an upper magnetic seal, a lower magnetic seal, MR material, and at least one sensor. The drum rotor has a first brake shear surface and a second brake shear surface. The first brake shear surface is on a rotor inner surface (RIS) of the drum rotor and the second brake shear surface is on a rotor outer surface (ROS) of the drum rotor. The pole ring has a pole ring shear surface on a pole ring inner surface (PRIS) that is fixedly positioned and positioned opposite the ROS. A second gap is positioned between the PRIS and the ROS. The core has an integrated coil and a core shear surface on a core outer surface (COS) that is positioned opposite the RIS. A first gap is positioned between the COS and the RIS. The rotating disk has an end. The drum rotor is connected to the end and the rotating disk is rotatably connected to the shaft. The MR material is disposed within the first gap and the second gap. The housing includes a housing cover that is fixed to a housing wall at a housing top edge of the housing wall. The housing also includes a sensor housing that is fixed to the housing wall at a housing bottom edge of the housing wall.

[0008] The upper magnetic seal is positioned to prevent movement of the MR material from the first gap through an upper void between the upper magnetic seal and the housing cover. The lower magnetic seal is positioned to prevent movement of the MR material from the second gap through a lower void between the lower magnetic seal and the core.

[0009] The TFD drum brake is controlled by a controller. The controller is in electronic communication with at least one sensor. A power source generates an electrical current. The power source is in electrical communication with the integrated coil. The controller is capable of controlling the electrical current from the power source and the magnetic flux is generated as a result of the electrical current being communicated to the integrated coil.

[0010] The present invention provides a circuit capable of saturating a drum rotor with magnetic flux. The circuit includes a core, a first gap having MR material disposed therein, a drum rotor, a second gap having MR material disposed therein, and a pole ring. The drum rotor is saturated when the magnetic flux passes through the circuit and when the magnetic flux reaches a threshold of about 1.3 Tesla (T).

[0011] The method step of energizing the integrated coil by applying an electrical current to the integrated coil generates the magnetic flux. The method step of magnetically saturating the drum rotor occurs with the generation of the magnetic flux. The step of magnetically saturating the drum rotor shears the first and second braking shear surfaces of the drum rotor against the MR material and each of the pole ring shear surface and the core shear surface. The method step of generating a resistive torque includes shearing of the MR material against the first and second braking shear surfaces, the pole ring shear surface, and the core shear surface to cause the resistive torque. BRIEF DESCRIPTION OF DRAWINGS

[0012] FIGS. 1a and 1b depict perspective views of a tactile feedback device (TFD) drum brake.

[0013] FIGS. 2a and 2b depict cross-sectional views of the TFD drum brake from FIGS. 1a and 1b.

[0014] Figure 3 is a detail view of the upper half of the TFD drum brake from FIGS. 2a and 2b.

[0015] Figure 4 is a detail view of the magnetic seals from FIGS. 2a and 2b.

[0016] Figure 5 is a schematic view of the magnetic flux of the TFD drum brake from FIGS. 2a and 2b.

[0017] Figure 6 is a cross-sectional view of the TFD drum brake from FIGS. 1a and 1b with a different magnetic seal configuration.

[0018] is a cross-sectional view of the TFD drum brake from FIGS. 1a and 1b with a different magnetic seal configuration.Figure 7 is a detail view of a magnetic seal from Figure 6

[0019] Figure 8 is a schematic view of magnetic flux from a TFD drum brake from Figure 6 DETAILED DESCRIPTION

[0020] Vehicles typically have a steering column and steering wheel to enable the vehicle to be steered. Many types of vehicles, such as cars, trucks, off-road equipment, watercraft, etc., now use steer-by-wire technology and require the use of feedback to the operator to give the operator a sense of resistance when the steering wheel is turned. As used, the term steering wheel encompasses a standard wheel, or anything that can be rotated. This feedback is provided by a haptic feedback device (TFD). In the inventions disclosed herein, the TFD is a TFD drum brake.

[0021] A typical magnetically responsive (MR) disc brake or a typical drum brake does not provide radial compactness. The TFD drum brake disclosed herein provides the advantages of a drum brake, but also adds a significant increase in torque provided by the MR material disposed within the TFD drum brake.

[0022] Referring to the drawings, FIGS. 1 through Figure 8 depicts a haptic feedback device (TFD) drum brake, generally designated as TFD drum brake 10. TFD drum brake 10 includes a housing 12 that encloses a shaft 14, a drum rotor 16, a core 18, a pole ring 20, a MR material 22, an upper magnetic seal 24, and a lower magnetic seal 26 therein. Housing 12 includes a housing wall 28. Housing wall 28 includes a housing top edge 30 and a housing bottom edge 32. A housing cover 34 is secured to housing top edge 30. Housing cover 34 is made of a non-magnetic material (e.g., 6061-T6 aluminum or similar material). A sensor housing 36 encloses drive electronics (not shown) for TFD drum brake 10 and is secured to housing bottom edge 32.

[0023] Shaft 14 is rotatably disposed within housing 12. Shaft 14 is rotatably supported by an upper bearing 38 and a lower bearing 40. Shaft 14 has a rotating disc 42 attached thereto and extending radially outward therefrom. Drum rotor 16 is connected to rotating disc 42 at an end 44 of rotating disc 42 and rotates with shaft 14. As shown in FIGS. 1 through Figure 3 ​​As shown, the drum rotor 16 extends radially outward from the end 44 and is perpendicular to the shaft 14 before curving parallel to the shaft 14 and perpendicular to the rotating disk 42. It is understood that the rotating disk 42 can extend radially outward and the drum rotor 16 can be parallel to the shaft 14 only. Additionally, the drum rotor 16 and the rotating disk 42 can be a single component that is directly attached to the shaft 14. In one embodiment, the drum rotor 16 has a thickness of between about 0.5 millimeters to about 5 millimeters. In another embodiment, the drum rotor 16 has a thickness of about 0.5 millimeters to about 1.5 millimeters.

[0024] A first braking shear surface 46 is located on a rotor inner surface (RIS) 48 of the drum rotor 16, while a second braking shear surface 50 is located on a rotor outer surface (ROS) 52 of the drum rotor 16. The RIS 48 faces radially inward, and the ROS 52 faces radially outward.

[0025] The core 18 is disposed about the shaft 14 and is non-rotatable relative to the shaft 14. The core 18 is positioned radially inward from the drum rotor 16. The core 18 includes an integrated coil 54. The core 18 has a core shear surface 56 on a core outer surface (COS) 58 that is positioned radially inward from and opposite the RIS 48. The space between the COS 58 and the RIS 48 forms a first gap 60 therebetween. The MR material 22 is disposed within the first gap 60.

[0026] The pole ring 20 is positioned and secured radially outward from the drum rotor 16 and is secured between a lower rim 62 of the cover, a lower seat 64 of the housing wall 28, and an inner wall surface 66. The pole ring 20 is fixedly positioned radially outward from the drum rotor 16. The pole ring 20 has a pole ring shear surface 68 on a pole ring inner surface (PRIS) 70. The PRIS 70 is positioned radially outward from and opposite the ROS 52. The space between the ROS 52 and the PRIS 70 forms a second gap 72 therebetween. The MR material 22 is also disposed within the second gap 72. A flow hole 45 is positioned proximate the end 44 and is part of the rotating disk 42. The flow hole 45 allows the MR material 22 to flow between the first gap 60 and the second gap 72.

[0027] In one embodiment, the first gap 60 and the second gap 72 each have a width of about 0.5 millimeters to about 2.0 millimeters. In another embodiment, the first gap 60 and the second gap 72 each have a width of about 0.5 millimeters to about 1.0 millimeters.

[0028] Referring to FIGS. 1 to Figure 4The upper magnetic seal 24 is positioned between the second gap 72, the rotating disk 42, and the lower edge 74 of the housing cover 34, with an upper void 76 formed therebetween. The upper magnetic seal 24 is positioned to prevent or inhibit the MR material 22 from moving from the second gap 72. The upper magnetic seal 24 includes a permanent magnet 78. The permanent magnet 78 is affixed to the rotating disk 42 and rotates therewith. An upper opening 80 is positioned between the upper void edge 82 of the second gap 72 and the permanent magnet 78. The upper magnetic seal 24 prevents the MR material 22 from entering the upper void 76 through the upper opening 80 and contaminating the upper bearing 38.

[0029] The lower magnetic seal 26 is positioned between the first gap 60, the rotating disk 42, and the upper edge 84 of the core 18, with a lower void 86 formed therebetween. The lower magnetic seal 26 includes a second permanent magnet 88. The lower magnetic seal 26 is positioned to prevent or inhibit the MR material 22 from moving from the first gap 60. The second permanent magnet 88 is affixed to the rotating disk 42 and rotates therewith. A lower opening 90 is positioned between the lower void edge 92 of the first gap 60 and the second permanent magnet 88. The lower magnetic seal 26 prevents the MR material 22 from entering the lower void 86 and contaminating the lower bearing 40.

[0030] In Figures 5 to 8 the alternative embodiment shown, the lower magnetic seal 26 is positioned affixed adjacent to the core 18, with the second permanent magnet 88 affixed to the core 18. The lower void 86 is positioned between a non-magnetic washer 94 and the lower opening 90. The non-magnetic washer 94 is positioned affixed to the rotating disk 42 and rotates therewith.

[0031] As Figure 5 and Figure 8 shown, in all embodiments, the polarity 95 of the lower magnetic seal 26 is opposite the polarity 97 of the pole ring 20. The rotating disk 42 provides a magnetic flux path for both the upper magnetic seal 24 and the lower magnetic seal 26.

[0032] Referring to FIGS. 1 through Figure 8 The MR material 22 is a dry, magnetically responsive powder that includes magnetizable particles that do not disperse within a liquid or oil carrier. The magnetizable particles of the material can include carbonyl iron, stainless steel, and / or any other magnetic material having various shapes, not limited to spherical. The MR material 22 is configured to provide a smooth torque that is proportional to the current, and it is independent of temperature.

[0033] As shown in FIGS. 2a, 2b, and Figure 6 At least one sensor 96 is positioned to monitor the rotation of the shaft 14.

[0034] Referring to FIGS. 1a through 2b, and Figure 6A controller 98 and a power supply 100 are included with the TFD drum brake 10. The power supply 100 is capable of generating an electrical current (not shown) and directly or indirectly electrically communicating the electrical current to the integrated coil 54. The power supply 100 is located externally to the TFD drum brake 10. The controller 98 is in electronic communication with at least the at least one sensor 96, the integrated coil 54, and the power supply 100. The controller can include a current amplifier (not shown) and at least one temperature sensor (not shown).

[0035] The controller 98 is capable of controlling the electrical current from the power supply 100 that is used to energize the integrated coil 54 and generate the magnetic flux 102. The control is provided using an algorithm related to end-stop torque for analog end-of-travel or using an algorithm related to torque for creating haptic feedback based on inputs such as steering force, vehicle speed, and other operational functions. The control also includes processing data related to rotation of the shaft 14 from at least the sensor 96.

[0036] The controller 98 increases or decreases the electrical current from the power supply 100 that is electrically communicated to the integrated coil 54. When a current amplifier is included, the electrical current is controlled by the current amplifier and the current amplifier is capable of increasing or decreasing the electrical current that is electrically communicated to the integrated coil 54. The current amplifier is used when the controller 98 is located integrally within the sensor housing 36 of the TFD drum brake 10. The current amplifier can be used when the controller 98 is located externally to the sensor housing 36 of the TFD drum brake 10.

[0037] Referring to Figure 5 and Figure 8 When the integrated coil 54 is energized with electrical current, the magnetic flux 102 is generated. The circuit 104 includes the core 18, the first gap 60 having the MR material 22 disposed therein, the drum rotor 16, the second gap 72 having the MR material 22 disposed therein, and the pole ring 20. The magnetic flux 102 passes through the circuit 104 and saturates the drum rotor 16. In other words, the controller 98 is capable of saturating the drum rotor 16 with the magnetic flux 102 that is generated by applying electrical current to the integrated coil 54. The magnetic flux 102 causes the MR material 22 to shear between the core shear plane 56 and the first brake shear plane 46, and between the second brake shear plane 50 and the pole ring shear plane 68. The torque is created in the TFD drum brake 10 as a result of the shearing.

[0038] The TFD drum brake 10 can be used on a vehicle (not shown). The vehicle typically has a steering column (not shown) and a steering wheel (not shown) to enable the vehicle to be steered. As discussed above, many vehicles now use steer-by-wire technology and require the use of feedback to the operator of the vehicle to give a sensation of resistance when the steering wheel is turned. For vehicles with a steering column, the TFD drum brake 10 is encapsulated therein. The shaft 15 of the TFD drum brake 10 is able to transmit the feedback force to the operator through the steering wheel.

[0039] In an embodiment, a method of providing haptic feedback using the TFD drum brake 10 is provided. The method includes generating a torque with the TFD drum brake 10 described above, energizing the integrated coil 54 by applying a current to the integrated coil 54, magnetically saturating the drum rotor 16, and generating a resistive torque.

[0040] The drum brake as described above and includes a housing 12 that encapsulates a shaft 14, a drum rotor 16, a pole ring 20, a core 18, a rotating disk 42, an upper magnetic seal 24, a lower magnetic seal 26, a MR material 22, and at least one sensor 96. The drum rotor 16 has a first brake shear surface 46 and a second brake shear surface 50. The first brake shear surface 46 is located on a rotor inner surface (RIS) 48 of the drum rotor 16 and the second brake shear surface 50 is located on a rotor outer surface (ROS) 52 of the drum rotor 16. The pole ring 20 has a pole ring shear surface 68 on a pole ring inner surface (PRIS) 70 that is fixedly positioned and positioned opposite the ROS 52. A second gap 72 is positioned between the PRIS 70 and the ROS 52. The core 18 has an integrated coil 54 and a core shear surface 56 on a core outer surface (COS) 58 that is positioned opposite the RIS 48. A first gap 60 is positioned between the COS (58) and the RIS 48. The rotating disk 42 has an end 44. The drum rotor 16 is connected with the end 44 and the rotating disk 42 is rotatably connected to the shaft 14. The MR material 22 is disposed within the first gap 60 and the second gap 72. The housing 12 includes a housing cover 34 fixed to the housing wall 28 at a housing top edge 30 of the housing wall 28. The housing 12 also includes a sensor housing 36 fixed to the housing wall 28 at a housing bottom edge 32 of the housing wall 28.

[0041] The upper magnetic seal 24 is positioned to capture MR material in the upper gap 76 and to prevent movement of the MR material 22 from the first gap 60 through the upper gap 76 between the upper magnetic seal 24 and the housing cover 34. The lower magnetic seal 26 is positioned to capture MR material in the lower gap 86 and to prevent movement of the MR material 22 from the second gap 72 through the lower gap 86 between the lower magnetic seal 26 and the core 18. The TFD drum brake 10 further includes at least one sensor 96.

[0042] The TFD drum brake 10 is controlled by a controller 98. The controller 98 is in electronic communication with the at least one sensor. A power source 100 generates an electrical current. The power source 100 is in electrical communication with the integrated coil 54. The controller 98 is capable of controlling the electrical current from the power source 100 and the magnetic flux 102 that results as a consequence of the electrical current being communicated to the integrated coil 54.

[0043] The circuit 104 is capable of saturating the drum rotor 16 with the magnetic flux 102. The circuit 104 includes the core 18, the first gap 60 having the MR material 22 disposed therein, the drum rotor 16, the second gap 72 having the MR material 22 disposed therein, and the pole ring 20. When the magnetic flux 102 passes through the circuit 104, the drum rotor 16 is saturated.

[0044] The method step of energizing the integrated coil 54 by applying an electrical current to the integrated coil 54 results in the magnetic flux 102.

[0045] The method step of magnetically saturating the drum rotor 16 occurs as a result of the magnetic flux 102. The step of magnetically saturating the drum rotor 16 results in the first brake shear surface 46 and the second brake shear surface 50 of the drum rotor 16 shearing against the MR material 22 and each of the pole ring shear surface 68 and the core shear surface 56.

[0046] The method step of generating a resistive torque includes shearing of the MR material 22 against the first brake shear surface 46, the second brake shear surface 50, the pole ring shear surface 68, and the core shear surface 56 to generate a resistive torque.

[0047] Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. Therefore, it is intended that the specification and examples be considered as exemplary only with the true scope and spirit of the invention being indicated by the following claims.

Claims

1. A haptic feedback device drum brake (10), comprising: a shaft (14) having a rotor disk (42) rotatably connected to the shaft; a drum rotor (16) connected to the rotor disk (42); a core (18) having an integrated coil (54) positioned radially inward from the drum rotor (16) forming a first gap (60) therebetween; a pole ring (20) fixedly positioned radially outward from the drum rotor (16) forming a second gap (72) therebetween; a magnetically responsive material (22) disposed within the first gap (60) and the second gap (72); an upper magnetic seal (24) positioned to prevent the magnetically responsive material (22) from moving from the second gap (72); a lower magnetic seal (26) positioned to prevent the magnetically responsive material (22) from moving from the first gap (60); a housing (12) enclosing the shaft (14), the drum rotor (16), the core (18), the upper magnetic seal (24), and the lower magnetic seal (26), the housing (12) having a housing cover (34) and a sensor housing (36) fixed thereto; and at least one sensor (96) capable of detecting rotation of the shaft (14).

2. The haptic feedback device drum brake (10) of claim 1, further comprising a controller (98) and an external power source (100), wherein the controller (98) is in electronic communication with the at least one sensor (96), the integrated coil (54), and the external power source (100), and the external power source (100) is capable of producing an electrical current, wherein the external power source (100) is in electrical communication with the integrated coil (54), wherein the controller (98) is capable of controlling the electrical current from the external power source (100) and a magnetic flux (102) generated by the integrated coil (54).

3. The haptic feedback device drum brake (10) of claim 2, further comprising a circuit (104) capable of saturating the drum rotor (16) with the magnetic flux (102), wherein the circuit (104) comprises the core (18), the first gap (60) having the magnetically responsive material (22) disposed therein, the drum rotor (16), the second gap (72) having the magnetically responsive material (22) disposed therein, and the pole ring (20), wherein the drum rotor (16) is saturated when the magnetic flux (102) passes through the circuit (104).

4. The haptic feedback device drum brake (10) of claim 2, wherein, the controller (98) is positioned entirely within the sensor housing (36) of the haptic feedback device drum brake (10).

5. The haptic feedback device drum brake (10) of claim 2, wherein, the controller (98) comprises a current amplifier and is capable of increasing or decreasing the electrical current electrically communicated to the integrated coil (54).

6. The haptic feedback device drum brake (10) of claim 1, wherein, The upper magnetic seal (24) includes a permanent magnet (78) positioned adjacent an upper opening (80), the upper opening (80) being located between the permanent magnet (78) and the housing cover (34), and wherein the lower magnetic seal (26) includes a second permanent magnet (88) positioned adjacent a lower opening (90), the lower opening (90) being located between the second permanent magnet (88) and the core (18).

7. The haptic feedback device drum brake (10) of claim 1, wherein, A controller (98) is capable of saturating the drum rotor (16) with magnetic flux (102) generated by applying current to the integrated coil (54).

8. The haptic feedback device drum brake (10) of claim 1, further comprising: a first brake shear surface (46) on the drum rotor (16) and a second brake shear surface (50) on the drum rotor (16), wherein the first brake shear surface (46) is located on a rotor inner surface (48) of the drum rotor (16) and the second brake shear surface (50) is located on a rotor outer surface (52) of the drum rotor (16); a pole ring shear surface (68) on a pole ring inner surface (70) of the pole ring (20), the pole ring inner surface (70) being located opposite the rotor outer surface (52), wherein a first gap (60) is located between the pole ring inner surface (70) and the rotor outer surface (52); and a core shear surface (56) on a core outer surface (58) of the core (18), the core outer surface (58) being located opposite the rotor inner surface (48), wherein a second gap (72) is located between the core outer surface (58) and the rotor inner surface (48).

9. The haptic feedback device drum brake (10) of claim 1, wherein, The drum rotor (16) has a thickness between about 0.5 millimeters and about 5 millimeters.

10. The haptic feedback device drum brake (10) of claim 1, wherein, The first gap (60) and the second gap (72) each have a width of about 0.5 millimeters to about 2.0 millimeters.

11. A haptic feedback device drum brake (10), comprising: a drum rotor (16) having a first brake shear surface (46) and a second brake shear surface (50), wherein the first brake shear surface (46) is located on a rotor inner surface (48) of the drum rotor (16) and the second brake shear surface (50) is located on a rotor outer surface (52) of the drum rotor (16); a pole ring (20) having a pole ring shear surface (68) on a pole ring inner surface (70) fixedly positioned and located opposite the rotor outer surface (52), wherein a second gap (72) is located between the pole ring inner surface (70) and the rotor outer surface (52); a core (18) having an integrated coil (54), the core (18) having a core shear surface (56) on a core outer surface (58) located opposite the rotor inner surface (48), wherein a first gap (60) is located between the core outer surface (58) and the rotor inner surface (48); and a core shear surface (56) on a core outer surface (58) of the core (18), the core outer surface (58) being located opposite the rotor inner surface (48), wherein a second gap (72) is located between the core outer surface (58) and the rotor inner surface (48). a rotating disk (42) having an end (44) where the drum rotor (16) is connected to the end (44) and the rotating disk (42) is rotatably connected to the shaft (14); an upper magnetic seal (24); a lower magnetic seal (26); a magnetically responsive material (22) disposed within the first gap (60) and the second gap (72); a housing (12) enclosing the shaft (14), the drum rotor (16), the pole ring (20), the core (18), the rotating disk (42), the upper magnetic seal (24), and the lower magnetic seal (26), the housing (12) including a housing cover (34) secured to a housing wall (28) at a housing top edge (30) of the housing wall (28), and a sensor housing (36) secured to the housing wall (28) at a housing bottom edge (32) of the housing wall (28); wherein the upper magnetic seal (24) is positioned to prevent movement of the magnetically responsive material (22) from the first gap (60) through an upper void (76) between the upper magnetic seal (24) and the housing cover (34), and the lower magnetic seal (26) is positioned to prevent movement of the magnetically responsive material (22) from the second gap (72) through a lower void (86) between the lower magnetic seal (26) and the core (18); and at least one sensor (96) capable of detecting rotation of the shaft (14).

12. The haptic feedback device drum brake (10) of claim 11, further comprising a controller (98) and an external power source (100), wherein the controller (98) is in electronic communication with the at least one sensor (96), the integrated coil (54), and the external power source (100), and the external power source (100) is capable of producing an electric current, wherein the external power source (100) is in electrical communication with the integrated coil (54), wherein the controller (98) is capable of controlling the electric current from the external power source (100) and a magnetic flux (102) produced by the integrated coil (54).

13. The haptic feedback device drum brake (10) of claim 12, further comprising a circuit (104) capable of saturating the drum rotor (16) with the magnetic flux (102), wherein the circuit (104) includes the core (18), the first gap (60) having the magnetically responsive material (22) disposed therein, the drum rotor (16), the second gap (72) having the magnetically responsive material (22) disposed therein, and the pole ring (20), wherein the drum rotor (16) is saturated when the magnetic flux (102) passes through the circuit (104).

14. The haptic feedback device drum brake (10) of claim 12, wherein, the controller (98) is positioned entirely within the sensor housing (36) of the haptic feedback device drum brake (10).

15. The haptic feedback device drum brake (10) of claim 14, wherein, The controller (98) includes a current amplifier and is capable of increasing or decreasing current electrically communicated to the integrated coil (54).

16. The haptic feedback device drum brake (10) of claim 11, wherein, The upper magnetic seal (24) includes a permanent magnet (78) positioned adjacent an upper opening (80) between the permanent magnet (78) and the housing cover (34), and wherein the lower magnetic seal (26) includes a second permanent magnet (88) positioned adjacent a lower opening (90) between the second permanent magnet (88) and the core (18).

17. The haptic feedback device drum brake (10) of claim 11, wherein, The drum rotor (16) has a thickness between about 0.5 millimeters and about 5 millimeters.

18. The haptic feedback device drum brake (10) of claim 11, wherein, The first gap (60) and the second gap (72) each have a width of about 0.5 millimeters to about 2.0 millimeters.

19. The haptic feedback device drum brake (10) of claim 11, wherein, The at least one sensor (96) is capable of detecting rotation of the shaft (14).

20. A method of providing haptic feedback using a haptic feedback device drum brake (10), the method comprising: generating torque with the haptic feedback device drum brake (10), the haptic feedback device drum brake comprising: a drum rotor (16) having a first brake shear surface (46) and a second brake shear surface (50), wherein the first brake shear surface (46) is on a rotor inner surface (48) of the drum rotor (16) and the second brake shear surface (50) is on a rotor outer surface (52) of the drum rotor (16); a pole ring (20) having a pole ring shear surface (68) on a pole ring inner surface (70) fixedly positioned and positioned opposite the rotor outer surface (52), wherein a second gap (72) is positioned between the pole ring inner surface (70) and the rotor outer surface (52); a core (18) having an integrated coil (54), the core (18) having a core shear surface (56) on a core outer surface (58) positioned opposite the rotor inner surface (48), wherein a first gap (60) is positioned between the core outer surface (58) and the rotor inner surface (48); a rotating disc (42) having an end (44), wherein the drum rotor (16) is connected to the end (44) and the rotating disc (42) is rotatably connected to a shaft (14); an upper magnetic seal (24); a lower magnetic seal (26); a magnetically responsive material (22) disposed within the first gap (60) and the second gap (72); a housing (12) enclosing the shaft (14), the drum rotor (16), the pole ring (20), the core (18), the rotating disc (42), the upper magnetic seal (24), and the lower magnetic seal (26), the housing (12) including a housing cover (34) fixed to a housing wall (28) at a housing top edge (30) of the housing wall (28), and a sensor housing (36) fixed to the housing wall (28) at a housing bottom edge (32) of the housing wall (28); wherein the upper magnetic seal (24) is positioned to prevent movement of the magnetically responsive material (22) from the first gap (60) through an upper void (76) between the upper magnetic seal (24) and the housing cover (34), and the lower magnetic seal (26) is positioned to prevent movement of the magnetically responsive material (22) from the second gap (72) through a lower void (86) between the lower magnetic seal (26) and the core (18); at least one sensor (96); a controller (98) in electronic communication with the at least one sensor (96); a power source (100) that generates an electrical current, the power source (100) being in electrical communication with the integrated coil (54), wherein the controller (98) is capable of controlling the electrical current from the power source (100) and a magnetic flux (102) that is generated as a result of the electrical current being communicated to the integrated coil (54); a circuit (104) that is capable of saturating the drum rotor (16) with the magnetic flux (102), wherein the circuit (104) includes the core (18), the first gap (60) having the magnetically responsive material (22) disposed therein, the drum rotor (16), the second gap (72) having the magnetically responsive material (22) disposed therein, and the pole ring (20), wherein the drum rotor (16) is saturated when the magnetic flux (102) passes through the circuit (104); energizing the integrated coil (54) by applying the electrical current to the integrated coil (54), the energizing generating the magnetic flux (102); magnetically saturating the drum rotor (16) with the magnetic flux (102), wherein the magnetic saturation causes the first brake shear surface (46) and the second brake shear surface (50) of the drum rotor (16) to shear against the magnetically responsive material (22) and each of the pole ring shear surface (68) and the core shear surface (56); and generating a resistive torque, wherein the resistive torque is generated in the shearing of the magnetically responsive material (22) against the first brake shear surface (46), the second brake shear surface (50), the pole ring shear surface (68), and the core shear surface (56). wherein the upper magnetic seal (24) is positioned to prevent movement of the magnetically responsive material (22) from the first gap (60) through an upper void (76) between the upper magnetic seal (24) and the housing cover (34), and the lower magnetic seal (26) is positioned to prevent movement of the magnetically responsive material (22) from the second gap (72) through a lower void (86) between the lower magnetic seal (26) and the core (18); at least one sensor (96); a controller (98) in electronic communication with the at least one sensor (96); a power source (100) that generates an electrical current, the power source (100) being in electrical communication with the integrated coil (54), wherein the controller (98) is capable of controlling the electrical current from the power source (100) and a magnetic flux (102) that is generated as a result of the electrical current being communicated to the integrated coil (54); a circuit (104) that is capable of saturating the drum rotor (16) with the magnetic flux (102), wherein the circuit (104) includes the core (18), the first gap (60) having the magnetically responsive material (22) disposed therein, the drum rotor (16), the second gap (72) having the magnetically responsive material (22) disposed therein, and the pole ring (20), wherein the drum rotor (16) is saturated when the magnetic flux (102) passes through the circuit (104); energizing the integrated coil (54) by applying the electrical current to the integrated coil (54), the energizing generating the magnetic flux (102); magnetically saturating the drum rotor (16) with the magnetic flux (102), wherein the magnetic saturation causes the first brake shear surface (46) and the second brake shear surface (50) of the drum rotor (16) to shear against the magnetically responsive material (22) and each of the pole ring shear surface (68) and the core shear surface (56); and generating a resistive torque, wherein the resistive torque is generated in the shearing of the magnetically responsive material (22) against the first brake shear surface (46), the second brake shear surface (50), the pole ring shear surface (68), and the core shear surface (56).

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