Transportation of long objects in unknown cluttered environments by a team of robots: A dynamical systems approach

Abstract

We present a distributed architecture for teams of two autonomous mobile robots that act in coordination in a joint transportation task of long objects. The team is able to perform its transportation task in unknown environments while avoiding static or moving obstacles. The working environment can be cluttered and with narrow passages such as corridors, corners and doors. These characteristics make our approach suitable to be deployed in warehouses or office-like environments. The control architecture of each robot is formalized as a non-linear dynamical system, where by design attractor states dominate. The overt behavior is smooth and stable, because it is generated as a time sequence of attractor states, for the control variables, which contributes to the overall asymptotically stability of the system that makes it robust against perturbations. We present results with real robots in a real indoor cluttered environment.

Multi-constrained joint transportation tasks by teams of autonomous mobile robots using a dynamical systems approach

“…The leader robot is further equipped with an omnidirectional vision system to detect target locations. All programming, control and computation are done onboard (see [8] for more details about the robots).…”

“…This has already been defined and evaluated in [8] for the helper and here it is also applied to the leader.…”

“…This is accomplished by a PID controller that depends on the displacement of the payload as measured by the helper. This approach was already presented in [8].…”

“…In [8] we developed control architectures that were tuned to teams of two robots, and that made the team able to perform in cluttered environments. A leader-helper strategy was employed, but the responsibility of avoiding collisions of the payload with obstacles was only assigned to the helper.…”

Attractor dynamics approach to joint transportation by autonomous robots: theory, implementation and validation on the factory floor

“…These constraints are of great importance, since they open up a range of possibilities of cargo displacement in application scenarios where autonomous robots must transport objects of different dimensions, in environments whose layout may change over time and which are co-inhabited by other vehicles or human operators. The projects reported in literature-including our prior work (Soares et al 2007;Machado et al 2013)-only focus on some of the abovementioned constraints (c.f. Sect.…”