# US 12,117,861 B2 · Magnetorheological fluid-based haptic knob apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,117,861 B2 - Document ID: US12117861B2 - Status: Granted - Kind: B2 - Application number: 18/054,141 - Filed: 2022-11-09 - Published: 2023-08-17 - Granted: 2024-10-15 - Earliest claimed: 2022-11-09 - Assignees: Hyundai Motor Company; Kia Corporation; Korea University of Technology and Education Industry-University Cooperation Foundation - Applicants: Hyundai Motor Company; Kia Corporation; Korea University Of Technology And Education Industry-University Cooperation Foundation - Inventors: Yoon Im; Yong Won Choi; Myung Hoe Kim; Joo Hwa Kim; In Ho Yun; Hyun U Ko; Sang Youn Kim - Web page: https://patentgrep.com/patent/US12117861B2 ## CPC - G05G 5/03: Means for enhancing the operator's awareness of arrival of the controlling member at a command or datum position; Providing feel, e.g. means for creating a counterforce (arrangements for indicating the position of the controlling member G05G1/015) - G05G 1/08: Controlling members for hand actuation by rotary movement, e.g. hand wheels - G06F 3/016: {Input arrangements with force or tactile feedback as computer generated output to the user} - G05G 2505/00: Means for preventing, limiting or returning the movements of parts of a control mechanism, e.g. locking controlling member - G05G: CONTROL DEVICES OR SYSTEMS INSOFAR AS CHARACTERISED BY MECHANICAL FEATURES ONLY ("Bowden" or like mechanisms F16C1/10; gearings or mechanisms not peculiar to this purpose F16H; speed changing or reversing mechanisms for gearings conveying rotary motion F16H59/00 - F16H63/00) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract In an embodiment a magnetorheological fluid-based haptic knob apparatus includes a housing, a solenoid coil mounted inside the housing, the solenoid coil configured to generate a magnetic field thereby providing magnetic flux, a shaft connected to the housing and including a rotational rod, wherein the shaft is configured to generate a plurality of modes and a magnetorheological fluid accommodated inside the housing, the magnetorheological fluid configured to form a magnetic chain in response of the magnetic flux. ## Claims ### Claim 1 A magnetorheological fluid-based haptic knob apparatus comprising: a housing; a solenoid coil mounted inside the housing, the solenoid coil configured to generate a magnetic field thereby providing magnetic flux; a shaft connected to the housing and configured to generate a plurality of modes; a magnetorheological fluid accommodated inside the housing, the magnetorheological fluid configured to form a magnetic chain in response of the magnetic flux; and a housing cover covering an open top of the housing, wherein the shaft comprises: a rotational rod, a main body rotatably arranged in the housing, and bumps configured to guide a flow of the magnetorheological fluid when the main body rotates. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the housing cover is shaped as a cylinder and has an opening at a top. ### Claim 3 (depends on 2) The apparatus of claim 2, wherein the rotational rod passes through a center of the housing cover. ### Claim 4 (depends on 3) The apparatus of claim 3, further comprising a sealing bearing holding the rotational rod in the center of the housing cover. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the bumps are obliquely mounted in a plurality of mounting areas located on the main body such that they form a gap through which the magnetorheological fluid is able to flow. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the shaft is configured to generate a shear mode and a flow mode by rotating the main body with the bumps. ### Claim 7 (depends on 1) The apparatus of claim 1, further comprising a control knob connected to the rotational rod and arranged on the housing so that the control knob is exposed to an outside, wherein the control knob configured to rotate the shaft. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein the control knob is configured to transfer a resistance to a user with different magnitudes by varying a viscosity of the magnetorheological fluid according to an amount of electric current applied to the solenoid coil. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein a resistance sensitivity is set when a plurality of resistances are produced in a combined manner by setting electric current signals to be applied to the solenoid coil to have different waveforms. ### Claim 10 (depends on 7) The apparatus of claim 7, wherein the control knob is configured to apply an electrical signal to the solenoid coil so that a viscosity of the magnetorheological fluid is varied and so that different resistances are provided. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the electrical signal is an electrical current having different waveforms. ### Claim 12 A magnetorheological fluid-based haptic knob apparatus comprising: a housing; a solenoid coil mounted inside the housing, the solenoid coil configured to generate a magnetic field thereby providing magnetic flux; a shaft connected to the housing and including a rotational rod, wherein the shaft is configured to generate a plurality of modes; and a magnetorheological fluid accommodated inside the housing, the magnetorheological fluid configured to form a magnetic chain in response of the magnetic flux, wherein the shaft comprises a main body rotatably arranged in the housing and bumps configured to guide a flow of the magnetorheological fluid when the main body rotates. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the bumps are obliquely mounted in a plurality of mounting areas located on the main body such that they form a gap through which the magnetorheological fluid is able to flow. ### Claim 14 (depends on 12) The apparatus of claim 12, wherein the shaft is configured to generate a shear mode and a flow mode by rotating the main body with the bumps. ### Claim 15 A magnetorheological fluid-based haptic knob apparatus comprising: a housing; a solenoid coil mounted inside the housing, wherein the solenoid coil is configured to generate a magnetic field thereby providing magnetic flux; a shaft connected to the housing and configured to generate a plurality of modes; a magnetorheological fluid accommodated inside the housing, wherein the magnetorheological fluid is configured to form a magnetic chain in response of the magnetic flux; and a control knob connected to a rotational rod and arranged on the housing so that the control knob is exposed to an outside, wherein the control knob is configured to rotate the shaft, and wherein the shaft comprises: the rotational rod, a main body rotatably arranged in the housing, and bumps configured to guide a flow of the magnetorheological fluid when the main body rotates. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the control knob is configured to transfer a resistance to a user with different magnitudes by varying a viscosity of the magnetorheological fluid according to an amount of electric current applied to the solenoid coil. ### Claim 17 (depends on 15) The apparatus of claim 15, wherein a resistance sensitivity is set when a plurality of resistances are produced in a combined manner by setting electric current signals to be applied to the solenoid coil to have different waveforms. ### Claim 18 (depends on 15) The apparatus of claim 15, wherein the control knob is configured to apply an electrical signal to the solenoid coil so that a viscosity of the magnetorheological fluid is varied and so that different resistances are provided. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein the electrical signal is an electrical current having different waveforms. ### Claim 20 (depends on 15) The apparatus of claim 15, wherein the bumps are obliquely mounted in a plurality of mounting areas located on the main body such that they form a gap through which the magnetorheological fluid is able to flow.