# US 2019/0375260 A1 · Suspension with active damping to tune caster dynamics > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0375260 A1 - Document ID: US20190375260A1 - Status: Published application - Kind: A1 - Application number: 16/005,080 - Filed: 2018-06-11 - Published: 2019-12-12 - Earliest claimed: 2018-06-11 - Assignees: Rivian Automotive, LLC - Applicants: Rivian Automotive, LLC - Inventors: Chass BAKKER - Web page: https://patentgrep.com/patent/US20190375260A1 ## CPC - B60G 17/0164: {mainly during accelerating or braking} - B60G 17/08: Characteristics of fluid dampers (adjusting fluid dampers in general F16F9/44 - F16F9/53) - B60G 3/20: all arms being rigid - B60G 3/207: {the arms being essentially parallel to the longitudinal axis of the vehicle} - B60G 17/019: characterised by the type of sensor or the arrangement thereof {(B60G17/01941 takes precedence)} - B62D 7/18: Steering knuckles; King pins - B62D 17/00: Means on vehicles for adjusting camber, castor, or toe-in - B60G 15/02: having mechanical spring - B60G 17/021: {the mechanical spring being a coil spring (B60G17/0272 takes precedence)} - B60G 2200/18: Multilink suspensions, e.g. elastokinematic arrangements - B60G 2200/464: Caster angle - B60G 2202/12: Wound spring - B60G 2202/312: The spring being a wound spring - B60G 2204/129: Damper mount on wheel suspension or knuckle - B60G 2204/62: Adjustable continuously, e.g. during driving - B60G 2400/05146: Wheel caster - B60G 2400/106: longitudinal with regard to vehicle, e.g. braking - B60G 2400/252: vertical - B60G 2500/10: Damping action or damper - B60G: VEHICLE SUSPENSION ARRANGEMENTS (air-cushion vehicles B60V; {cycle suspensions B62K25/00}) - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) ## Abstract A suspension assembly for a vehicle having a frame includes a control arm, knuckle, spring, damper, and control module. The control arm is pivotably coupled to the frame. The knuckle is coupled to the control arm and supports a wheel hub for rotation relative to the knuckle. The spring is mounted between the frame and the control arm or the knuckle. The damper has an adjustable damping force and includes a first end mounted to the frame and a second end mounted such that a change in caster angle of the knuckle extends or contracts the damper. The control module is in communication with the damper and configured to adjust a damping force of the damper based on an actual or predicted change in caster angle of the knuckle. The control module is configured to increase the damping force in a direction that resists a change in the caster angle. ## Claims ### Claim 1 A suspension assembly for a vehicle having a frame, the suspension assembly comprising: a control arm pivotably coupled to the frame; a knuckle coupled to the control arm and adapted to support a wheel hub for rotation relative to the knuckle; a spring mounted between the frame and either the control arm or the knuckle; a damper having an adjustable damping force and including a first end mounted to the frame and a second end mounted such that a change in caster angle of the knuckle extends or contracts the damper; and a control module in communication with the damper and configured to adjust a damping force of the damper based on an actual or predicted change in caster angle of the knuckle, the control module being configured to increase the damping force in a direction that resists a change in the caster angle. ### Claim 2 (depends on 1) The suspension assembly of claim 1, wherein the damper is disposed either forward or rearward of a kingpin axis of the suspension assembly. ### Claim 3 (depends on 1) The suspension assembly of claim 1, wherein one of the spring and the damper is disposed forward of the kingpin axis and the other of the spring and the damper is disposed rearward of the kingpin axis. ### Claim 4 (depends on 1) The suspension assembly of claim 1, wherein the second end of the damper is mounted to the knuckle. ### Claim 5 (depends on 1) The suspension assembly of claim 1, further comprising a first sensor configured to detect a first characteristic of the vehicle, wherein the control module is configured to receive a first signal representative of the first characteristic from the first sensor and to adjust the damping force of the damper based on the first characteristic. ### Claim 6 (depends on 5) The suspension assembly of claim 5, wherein the first characteristic is one of an acceleration of the vehicle, a deceleration of the vehicle, and a change in angular position of the knuckle relative to the frame. ### Claim 7 (depends on 5) The suspension assembly of claim 5, wherein the control module is configured to calculate the caster angle based on the first signal and at least one second characteristic of the vehicle. ### Claim 8 (depends on 7) The suspension assembly of claim 7, wherein the at least one second characteristic is one of a ride height and a length of the damper. ### Claim 9 (depends on 8) The suspension assembly of claim 8, further comprising a second sensor configured to detect a length of the damper. ### Claim 10 (depends on 1) The suspension assembly of claim 1, further comprising a toe link and a camber link, the toe link including a first end mounted to the knuckle at a first location on the knuckle, a second end coupled to the frame, and a first rigid body extending between the first and second ends, the camber link including a third end mounted to the knuckle at a second location on the knuckle, a fourth end coupled to the frame, and a second rigid body extending between the third and fourth ends, the control arm being mounted to the knuckle at a third location on the knuckle. ### Claim 11 (depends on 10) The suspension assembly of claim 10, wherein the second end of the damper is mounted to one of the control arm, the toe link, and the camber link. ### Claim 12 (depends on 1) The suspension assembly of claim 1, further comprising a first bushing and a second bushing, the first and second bushings being mounted in a force transmission path between the knuckle and the frame and configured to provide the knuckle with a first degree of compliance in a first rotational direction and a second degree of compliance in a second direction, the first degree of compliance being greater than the second degree of compliance. ### Claim 13 (depends on 12) The suspension assembly of claim 12, wherein the first bushing is mounted to the knuckle and the second bushing is mounted to one of the control arm, a toe link, a camber link, and an integral link. ### Claim 14 A suspension assembly for a vehicle having a frame, the suspension assembly comprising: a knuckle adapted to support a wheel hub for rotation relative to the knuckle; a plurality of control arms, each control arm including a first end coupled to the frame, a second end coupled to the knuckle, and a rigid body extending between the first and second ends of the control arm; a spring mounted between the frame and either the knuckle or one of the control arms; a damper having an adjustable damping force and including a first end coupled to the frame and a second end mounted to either the knuckle or one of the control arms such that a change in caster angle of the knuckle extends or contracts the damper; a first sensor configured to detect a first characteristic of the vehicle and output a first signal representative of the first characteristic; and a control module in communication with the damper and the sensor, the control module configured to receive the first signal and determine an actual or predicted change in caster angle of the knuckle based on the first characteristic, the control module configured to increase a damping force of the damper in a direction that resists the change in caster angle. ### Claim 15 (depends on 14) The suspension assembly of claim 14, wherein the first characteristic is one of an acceleration of the vehicle, a deceleration of the vehicle, and a change in angular position of the knuckle relative to the frame. ### Claim 16 (depends on 14) The suspension assembly of claim 14, wherein the control module is configured to calculate the caster angle based on the first characteristic and at least one second characteristic of the vehicle. ### Claim 17 (depends on 16) The suspension assembly of claim 16, wherein the at least one second characteristic is one of a ride height and a length of the damper. ### Claim 18 A method of controlling a caster angle of a knuckle of a vehicle, the vehicle including a damper having an adjustable damping force and including one end coupled to the knuckle or a control arm such that a change in caster angle of the knuckle extends or contracts the damper, the method comprising: detecting at a first sensor a first characteristic of the vehicle; receiving at a control module a first input from the first sensor, the first input representative of the first characteristic; determining at the control module an actual or predicted change in caster angle of the knuckle based on the first input; and adjusting a damping force of the damper in a direction that resists the actual or predicted change in caster angle. ### Claim 19 (depends on 18) The method of claim 18, wherein adjusting the damping force of the damper includes increasing the damping force in a first direction that resists rotation of the knuckle away from a preferred caster angle and decreasing the damping force in a second direction that that permits rotational change of the knuckle toward the preferred caster angle. ### Claim 20 (depends on 18) The method of claim 18, wherein determining the actual or predicted change in caster angle includes calculating the caster angle based on at least one of an acceleration of the vehicle, a deceleration of the vehicle, a change in angular position of the knuckle, and a length of the damper.