System and method for providing a corrected lane following path through a curve for trailering vehicles

Patent metadata

Field	Value
Publication number	US-9849878-B2
Application number	US-201615054705-A
Country	US
Kind code	B2
Filing date	Feb 26, 2016
Priority date	Feb 26, 2016
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

A method for providing vehicle steering control through a curve in an autonomously driven or semi-autonomously driven vehicle that is towing a trailer. The method determines that the trailer will cross out of the travel lane based on the curvature of the curve and the turn radius of the trailer. The method calculates a start turn radius of the vehicle for a start location of the curve, an end turn radius of the vehicle for an end location of the curve, and a turn end point proximate the end location or a turn start point proximate the start location. The method provides initial and boundary conditions for determining a desired path of the vehicle through the curve that prevents the trailer from crossing out of the lane and determines the desired path based on the initial and boundary conditions by solving a polynomial equation.

First claim

What is claimed is:

1. A method for providing vehicle steering control in an autonomously driven or semi-autonomously driven vehicle that is towing a trailer so as to prevent the trailer from crossing out of a travel lane in a curve that the vehicle is traveling along, said method comprising:
using a processor programmed for:
determining a radius of curvature of the curve, a width of the travel lane, and a length of the trailer;
determining when the vehicle has entered the curve;
determining a current steering angle of the vehicle;
determining a current turn radius of the vehicle for traveling through the curve using the current steering angle;
determining a turn radius of the trailer using the current turn radius of the vehicle and other parameters;
determining that the trailer will cross out of the travel lane based on the radius of curvature of the curve and the turn radius of the trailer;
calculating a start turn radius of the vehicle for a start location of the curve;
calculating an end turn radius of the vehicle for an end location of the curve;
determining a turning end point proximate the end location;
determining a turning start point proximate the start location; and
determining a desired path of the vehicle through the curve that prevents the trailer from crossing out of the lane that includes solving a polynomial equation using the start turn radius, the end turn radius and the turning end point or the turning start point; and

steering the vehicle using a steering system along the desired path through the curve.

2. The method according to claim 1 wherein determining the desired path includes solving the polynomial equation as:
y n ( x n )= a 0 +a 1 x n +a 2 x n 2 +a 3 x n 3 +a 4 x n 4 +a 5 x n 5 ,
0 ≤ x n = x v x ⁢ Δ ⁢ ⁢ T ≤ 1 , y n =y/L,

where x is vehicle longitudinal travel distance, y is vehicle lateral travel distance with respect to a current vehicle location, v x is vehicle speed, a 0 -a 5 are coefficients, L is the width of the travel lane, and ΔT is the time for traveling through the curve.

3. The method according to claim 2 wherein determining the desired path includes determining a desired path through the curve that starts at a beginning location of the curve, has a relatively wide turn through the curve, and ends before an ending location of the curve.

4. The method according to claim 3 further comprising providing initial conditions to solve the polynomial equation at the turning start point as:
y n (0)=0,
y′ n (0)=0,

y
n
″

⁡

(
0
)

=

(

v
x

⁢
Δ
⁢

⁢
T

)

2

R
f

⁢
L

,

and providing boundary conditions to solve the polynomial equation at the turning end point as:

y
n

⁡

(
1
)

=

y
lane

⁡

(

v
x

⁢
Δ
⁢

⁢
T

)

+
L

L

,

⁢

y
n
′

⁡

(
1
)

=

y
lane
′

⁡

(

v
x

⁢
Δ
⁢

⁢
T

)

·

v
x

⁢
Δ
⁢

⁢
T

L

,

⁢

y
n
″

⁡

(
1
)

=

2
⁢

(

v
x

⁢
Δ
⁢

⁢
T

)

2

Assignees

• Gm Global Tech Operations Llc

Inventors

• Lee Jin-Woo
• Litkouhi Bakhtiar B

Classifications

• B60W2300/14

  Tractor-trailers, i.e. combinations of a towing vehicle and one or more towed vehicles, e.g. caravans; Road trains · CPC title

• B60W40/072

  Curvature of the road · CPC title

• B60W30/18163

  Lane change; Overtaking manoeuvres · CPC title

• B60W2540/18

  Steering angle · CPC title

• B60W30/18145

  Cornering · CPC title