Method and apparatus for responding to road surface discontinuities

Patent metadata

Field	Value
Publication number	US-2021394573-A1
Application number	US-201917285174-A
Country	US
Kind code	A1
Filing date	Oct 18, 2019
Priority date	Oct 19, 2018
Publication date	Dec 23, 2021
Grant date	—

Abstract

Disclosed embodiments are related to suspension systems including dampers and suspension actuators and related methods of control for mitigating the effects of potholes and other road surface discontinuities.

First claim

1 . A method of controlling an active suspension actuator of a suspension assembly of a vehicle, the method comprising:
collecting information about a pothole that has a floor and a length along a direction of travel of the vehicle; based at least partially on the information about the pothole, selecting one of at least two strategies for traversing the pothole with a wheel of a first suspension assembly, wherein a first strategy includes traversing most of the length while the wheel of the first suspension assembly is airborne and a second strategy includes traversing more than half of the length while the wheel of the first suspension assembly is in contact with the pothole floor; activating a damping element of the first suspension assembly of the vehicle; and implementing the selected strategy.

2 . The method of claim 1 , further comprising collecting information about the vehicle, wherein selecting the strategy is also based on the information about the vehicle.

3 . The method of claim 2 , wherein information about the vehicle is selected from the group consisting of speed of the vehicle and mass distribution of a sprung mass of the vehicle.

4 . The method of claim 3 , wherein the information about the pothole includes a position of the vehicle relative to the pothole.

5 . The method of claim 4 , further comprising collecting information about the pothole with the controller, wherein the information is selected from the group consisting of map data, GPS data, terrain-based localization data, data from a wheel other than the first wheel of the vehicle.

6 . The method of claim 1 , wherein the selected strategy is the first strategy.

7 . The method of claim 6 , further comprising estimating a projected mismatch distance when the first wheel is at the end of the pothole.

8 . The method of claim 7 , further comprising applying a predetermined compressive force with the actuator of the first suspension assembly at least during the period when the wheel, of the first suspension assembly, is airborne.

9 . The method of claim 7 , further comprising increasing the ride height of the vehicle by using an actuator of a second suspension assembly during the period when the wheel of the first suspension assembly is traversing the pothole.

10 . The method of claim 8 , further comprising increasing the ride height of the vehicle by using an actuator of a second suspension assembly during the period when the wheel of the first suspension assembly is traversing the pothole.

11 . The method of claim 10 , further comprising increasing the ride height of the vehicle by using an actuator of a third suspension assembly during the period when the wheel of the first suspension assembly is traversing the pothole.

12 . The method of claim 11 , further comprising applying a predetermined compressive force with the actuator of a fourth suspension assembly at least during the period when the wheel, of the first suspension assembly, is airborne, wherein the fourth suspension assembly is at a corner of the vehicle located diagonally opposite to a corner where the first suspension assembly is located.

13 . The method of claim 6 further comprising locking the actuator of the first suspension assembly to prevent extension of the actuator at least during the period when the wheel, of the first suspension assembly, is airborne.

14 . A method of controlling an active suspension system of a vehicle, the method comprising:
detecting a discontinuity in a road surface; traversing the discontinuity with a wheel of a first suspension assembly of the active suspension system; controlling a suspension actuator of the first suspension assembly to apply a compressive force on a spring element operationally interposed between the vehicle's sprung mass and the wheel of the first suspension assembly; and keeping the wheel of the first suspension assembly airborne during at least a portion of the wheel traversing the discontinuity.

15 . The method of claim 14 further comprising controlling a suspension actuator of at least a second suspension assembly with a controller, at least during the period when the wheel of the first suspension assembly is airborne, to apply an extension force on a spring element operationally interposed between the vehicle's sprung mass and a wheel of the second suspension assembly.

16 . The method of claim 15 further comprising controlling a suspension actuator of a third suspension assembly with a controller, at least during the period when the wheel of the first suspension assembly is airborne, to apply a compressive force on a spring element operationally interposed between the vehicle's sprung mass and a wheel of the third suspension assembly.

17 . The method of claim 16 wherein the discontinuity is a pothole.

18 . A suspension system of a vehicle comprising:
a first suspension assembly that includes:
a spring element operationally interposed between the vehicle's sprung mass and a wheel assembly;
a damping element, operationally interposed between the vehicle's sprung mass and the wheel assembly in parallel with the spring element, that includes:
a hydraulic cylinder with a piston, connected to a piston rod, that separates the hydraulic cylinder into a compression volume and an extension volume; and
a valve assembly configured to block fluid flow from the extension volume in a first mode of operation while allowing fluid flow into the extension volume during the first mode of operation.

19 . The suspension system of claim 18 wherein the valve assembly is further configured to allow fluid flow into and out of the extension volume during a second mode of operation.

20 . The suspension system of claim 19 wherein the valve assembly includes at least one valve that is electrically controlled.

21 .- 41 . (canceled)

Assignees

• Clearmotion Inc

Inventors

• Vente Gert-Jan Alexander
• Taylor Matthew Jo

Classifications

• B60G2202/416

  using a pump, e.g. in the line connecting the lower chamber to the upper chamber of the actuator · CPC title

• B60G2500/32

  of only one vehicle part or side · CPC title

• B60G2400/821

  Uneven, rough road sensing affecting vehicle body vibration · CPC title

• B60G2400/61

  Load distribution · CPC title

• B60G2400/204

  Vehicle speed · CPC title