Motion and Trajectory Planning

Safe trajectory tracking using closed-form controllers based on control barrier functions

This paper considers the problem of guaranteeing avoidance of critical state space regions during tracking of reference trajectories for systems with dynamics equivalent to r-th order decoupled integrators. The necessity to avoid those critical regions during trajectory tracking may arise during...
Kinematic Control of Redundant Robots with Online Handling of Variable Generalized Hard Constraints

We present a generalized version of the Saturation in the Null Space (SNS) algorithm for the task control of redundant robots when hard inequality constraints are simultaneously present both in the joint and in the Cartesian space. These hard bounds should never be violated, are treated equally and...
Decidability in robot manipulation planning

Consider the problem of planning collision-free motion of n objects movable through contact with a robot that can autonomously translate in the plane and that can move a maximum of m ≤ n objects simultaneously. This represents the abstract formulation of a general class of manipulation planning...
Exploiting Robot Redundancy for Online Learning and Control

Accurate trajectory tracking in the task space is critical in many robotics applications. Model-based robot controllers are able to ensure very good tracking but lose effectiveness in the presence of model uncertainties. On the other hand, online learning-based control laws can handle poor dynamic...
Motion Control of Redundant Robots with Generalised Inequality Constraints

We present an improved version of the Saturation in the Null Space (SNS) algorithm for redundancy resolution at the velocity level. In addition to hard bounds on joint space motion, we consider also Cartesian box constraints that cannot be violated at any time. The modified algorithm combines all...
Task Priority Matrix at the Acceleration Level: Collision Avoidance Under Relaxed Constraints

We propose a new approach for executing the main Cartesian tasks assigned to a redundant robot while guaranteeing whole-body collision avoidance. The robot degrees of freedom are fully utilized by introducing relaxed constraints in the definition of operational and collision...
Formation Mission Design for Commercial Aircraft

Abstract

In this talk, a technique to solve the formation mission design problem for commercial aircraft will be described. Given the departure times and the departure and arrival locations of several commercial flights, the relevant weather forecast, and the expected...
Task Priority Matrix Under Hard Joint Constraints

We propose an extension to the Task Priority Matrix (TPM) method for redundancy resolution that includes also hard inequality joint constraints. This is done by combining TPM with a modified version of the basic Saturation in the Null Space (SNS) algorithm. Comparative simulations are reported for...
On Time-Optimal Control of Elastic Joints under Input Constraints

We highlight the equivalence between the motion of an elastic joint and the two-body problem in classical mechanics. Based on this observation, a change of coordinates is introduced that reduces the two-body problem to a pair of decoupled one-body problems. This allows to treat the rest-to-rest...
Least Conservative Linearized Constraint Formulation for Real-Time Motion Generation

Today robotics has shown many successful strategies to solve several navigation problems. However, moving into a dynamic environment is still a challenging task. This paper presents a novel method for motion generation in dynamic environments based on real-time nonlinear model predictive control (...