A Lyapunov Guidance Vector Field Based Continuous Curvature Path Generation for Waypoint Following of UAVs

Author(s):  
Tammineni Harinarayana ◽  
Siva Vignesh Krishnan ◽  
Sikha Hota ◽  
Rahul Kushwaha
Author(s):  
Eric L. Faulring ◽  
J. Edward Colgate

During human-cobot interaction, transitions often occur between free mode operation and constraint surface following. This paper considers the following typical scenario: an operator of a three-dimensional (e.g. x-y-z or x-y-θ) cobot commands a “join” from free mode to a one-dimensional constraint path. To ensure that this transition is smooth and responsive, a “blend path” is computed that joins the cobot’s initial location to a location on the constraint path. The blend path must match tangency and curvature at each end, and must also exhibit continuous curvature. A novel “triple-clothoid” algorithm is developed that meets these requirements. In addition, we demonstrate that the triple-clothoid is particularly amenable to x-y-θ systems via implementation on a planar cobot.


Author(s):  
Shuoxue Sun ◽  
Yuwen Sun ◽  
Jinting Xu ◽  
Yuan-Shin Lee

This paper presents a new vector-field-based streamline smoothing method in the parametric space and a tool orientation optimization technique for five-axis machining of complex compound surfaces with torus-end cutters. Iso-planar tool path is widely used in the machining of various types of surfaces, especially for the compound surface with multiple patches, but the operations of intersecting the compound surface with a series of planes have depended considerably on the complicated optimization methods. Instead of intersecting the surface directly with planes, a novel and effective tool path smoothing method is presented, based on the iso-planar feed vector fields, for five-axis milling of a compound surface with torus-end cutters. The iso-planar feed vector field in the parametric domain is first constructed in the form of stream function that is used to generate the candidate streamlines for tool path generation. Then, a G1 blending algorithm is proposed to blend the vector fields within the adjacent parametric domains to ensure smooth transition of cross-border streamlines. Based on the smoothened streamlines in the parametric domains, pathlines along with their correspondent side sizes are selected as desirable tool paths. Concerning a high performance machining, detailed computational techniques to determine the tool axis orientation are also presented to ensure, at each cutter contact (CC) point, the torus-end cutter touches the part surface closely without gouging. Both the computational results and machined examples are demonstrated for verification and validation of the proposed methods.


2013 ◽  
Vol 34 (4) ◽  
pp. 183-198 ◽  
Author(s):  
Anastasios M. Lekkas ◽  
Andreas Reason Dahl ◽  
Morten Breivik ◽  
Thor I. Fossen

2008 ◽  
Vol 56 (4) ◽  
pp. 360-372 ◽  
Author(s):  
F. Gómez-Bravo ◽  
F. Cuesta ◽  
A. Ollero ◽  
A. Viguria

2018 ◽  
Vol 9 (4) ◽  
pp. 557-570 ◽  
Author(s):  
Federico Pinchetti ◽  
Alexander Joos ◽  
Walter Fichter

Sign in / Sign up

Export Citation Format

Share Document