A Time-Varying Lookahead Distance Guidance Law for Path Following

Lekkas, Anastasios M.; Fossen, Thor I.

doi:10.3182/20120919-3-it-2046.00068

Cited by 88 publications

(46 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The look-ahead distance can be made time-dependent using optimization techniques (Pavlov et al, 2009) or explicit formulae (Lekkas and Fossen, 2012).…”

Section: Kinematic Equationsmentioning

confidence: 99%

On uniform semiglobal exponential stability (USGES) of proportional line-of-sight guidance laws

Fossen¹,

Pettersen²

2014

Automatica

Self Cite

221

105

View full text Add to dashboard Cite

This paper presents a uniform semiglobal exponential stability (USGES) proof for a class of proportional line-of-sight (LOS) guidance laws used for vehicle path-following control. The LOS guidance law under consideration is a lookahead-based guidance law for marine craft. The USGES proof extends previous results that only guarantee global κ-exponential stability. Typical applications are marine craft and aircraft motion control systems for path following where the total system is a cascade of the motion controller and guidance law error dynamics.

show abstract

“…The look-ahead distance can be made time-dependent using optimization techniques (Pavlov et al, 2009) or explicit formulae (Lekkas and Fossen, 2012).…”

Section: Kinematic Equationsmentioning

confidence: 99%

On uniform semiglobal exponential stability (USGES) of proportional line-of-sight guidance laws

Fossen¹,

Pettersen²

2014

Automatica

Self Cite

221

105

View full text Add to dashboard Cite

show abstract

“…For the issue of time-varying ∆, Pavlov et al presented a nonlinear model predictive control (MPC) approach, which can adjust its value online to achieve smaller overshoot and faster convergence speed compared with the constant ∆ [12]. A function to adjust ∆ according to the cross-track error was given in [13]. In [10], only the cross-track was considered, but in this note, both cross-track error and along-track error are taken into account, which is more universal.…”

Section: Introductionmentioning

confidence: 99%

“…There is very much literature investigating the design of the path following controller, and different algorithms are introduced into it, such as classic and variant PID control [13,14], fuzzy control [15], sliding mode control [16], backstepping control [17], and so on. According to engineering practice, the ship model has the characteristics of nonlinearity and uncertainty due to the continuous change of operating conditions.…”

Section: Introductionmentioning

confidence: 99%

Adaptive LOS Path Following for a Podded Propulsion Unmanned Surface Vehicle with Uncertainty of Model and Actuator Saturation

Wang

Fan

et al. 2017

Applied Sciences

View full text Add to dashboard Cite

This paper addresses three related issues concerning the path following control of a podded propulsion unmanned surface vehicle (USV), namely modeling, guidance and control. The pod is different from the general propeller-rudder propulsion device, and its essence is a vector thruster. Therefore, first, through various assumptions and simplification, the three-degree of freedom (DOFs) planar motion model of the podded propulsion USV is established. Then, the classical line-of-sight (LOS) guidance strategy is improved by adaptive sideslip angle and a time-varying lookahead distance. Based on the guidance system, the corresponding controllers for yaw rate and surge speed are presented, which are combined by backstepping technology, the neural network minimum parameter learning method and the neural shunting model. Specifically, the neural network minimum parameter learning method is proposed to compensate the uncertainty of the model and the immeasurability of external disturbances, and the neural shunting model is employed to cope with the "explosion of complexity" problem of backstepping. Meanwhile, an auxiliary dynamic system is introduced to prevent actuator saturation (input saturation). All error signals of the system are proven to be uniformly ultimately bounded (UUB) by employing Lyapunov stability theory. Finally, two numerical simulations are given to prove the correctness of the proposed scheme.

show abstract

“…Regarding the guidance problem, the contribution of this paper is the continuation of the work of [33] using a modified formula for and extending the method to curved path following. A globally exponentially stable (GES) sliding mode controller is designed for stabilizing the yaw angle of the vehicle and acts as the perturbing system in the cascade system that it forms along with the well-known LOS guidance law [36], which now incorporates the time-varying look ahead distance equation.…”

mentioning

confidence: 99%

“…In [32], the LOS guidance parameter was embedded in the linear MPC controller design as as additional decision variable and the simulations indicated a smoother convergence to a straight line compared with the linear MPC controller with a fixed lookahead distance. In [33], different direction was followed by proposing a time-varying lookahead distance equation, which is dependent on the cross-track error. This results in lower values for (and thus a more agile and aggressive response) when the vehicle is far from the desired path, and greater values when the vehicle is closer to the path and less abrupt behavior is needed so as to avoid oscillating around the path.…”

mentioning

confidence: 99%

Integral LOS Path Following for Curved Paths Based on a Monotone Cubic Hermite Spline Parametrization

Lekkas

Fossen

2014

IEEE Trans. Contr. Syst. Technol.

Self Cite

305

140

View full text Add to dashboard Cite

This paper addresses two interrelated problems concerning the planar three degree-of-freedom motion of a vehicle, namely, the path planning problem and the guidance problem. The monotone cubic Hermite spline interpolation (CHSI) technique by Fritsch and Carlson is employed to design paths that provide the user with better shape control and avoid wiggles and zigzags between the two successive waypoints. The conventional line-of-sight (LOS) guidance law is modified by proposing a time-varying equation for the lookahead distance, which is a function of the cross-track error. This results in a more flexible maneuvering behavior that can contribute to reaching the desired path faster as well as obtaining a diminished oscillatory behavior around the desired path. The guidance system along with a heading controller form a cascaded structure, which is shown to be κ-exponentially stable when the control task is to converge to the path produced by the aforementioned CHSI method. In addition, the issue of compensating for the sideslip angle β is discussed and a new κ-exponentially stable integral LOS guidance law, capable of eliminating the effect of constant external disturbances for straight-line path following, is derived.

show abstract

A Time-Varying Lookahead Distance Guidance Law for Path Following

Cited by 88 publications

References 16 publications

On uniform semiglobal exponential stability (USGES) of proportional line-of-sight guidance laws

On uniform semiglobal exponential stability (USGES) of proportional line-of-sight guidance laws

Adaptive LOS Path Following for a Podded Propulsion Unmanned Surface Vehicle with Uncertainty of Model and Actuator Saturation

Integral LOS Path Following for Curved Paths Based on a Monotone Cubic Hermite Spline Parametrization

Contact Info

Product

Resources

About