Tag Archives: Deliberative Navigation

Using reasoning to improve low-level robot navigation

Muhayyuddin, Aliakbar AkbariJan Rosell, A Real-Time Path-Planning Algorithm based on Receding Horizon Techniques, Journal of Intelligent & Robotic Systems, September 2018, Volume 91, Issue 3–4, pp 459–477, DOI: 10.1007/s10846-017-0698-z.

Physics-based motion planning is a challenging task, since it requires the computation of the robot motions while allowing possible interactions with (some of) the obstacles in the environment. Kinodynamic motion planners equipped with a dynamic engine acting as state propagator are usually used for that purpose. The difficulties arise in the setting of the adequate forces for the interactions and because these interactions may change the pose of the manipulatable obstacles, thus either facilitating or preventing the finding of a solution path. The use of knowledge can alleviate the stated difficulties. This paper proposes the use of an enhanced state propagator composed of a dynamic engine and a low-level geometric reasoning process that is used to determine how to interact with the objects, i.e. from where and with which forces. The proposal, called κ-PMP can be used with any kinodynamic planner, thus giving rise to e.g. κ-RRT. The approach also includes a preprocessing step that infers from a semantic abstract knowledge described in terms of an ontology the manipulation knowledge required by the reasoning process. The proposed approach has been validated with several examples involving an holonomic mobile robot, a robot with differential constraints and a serial manipulator, and benchmarked using several state-of-the art kinodynamic planners. The results showed a significant difference in the power consumption with respect to simple physics-based planning, an improvement in the success rate and in the quality of the solution paths.

Real-time trajectory generation for omnidirectional robots, and a good set of basic bibliographical references

Tamás Kalmár-Nagy, Real-time trajectory generation for omni-directional vehicles by constrained dynamic inversion, Mechatronics, Volume 35, May 2016, Pages 44-53, ISSN 0957-4158, DOI: 10.1016/j.mechatronics.2015.12.004.

This paper presents a computationally efficient algorithm for real-time trajectory generation for omni-directional vehicles. The algorithm uses a dynamic inversion based approach that incorporates vehicle dynamics, actuator saturation and bounded acceleration. The algorithm is compared with other trajectory generation algorithms for omni-directional vehicles. The method yields good quality trajectories and is implementable in real-time. Numerical and hardware tests are presented.