M.Sc Thesis | |

M.Sc Student | Guy Eran |
---|---|

Subject | Navigation Algorithm for Plan Spider Robot in Smooth Intermittent-Linear Tunnel |

Department | Department of Mechanical Engineering |

Supervisor | PROF. Elon Rimon |

The objective of this research is
to develop an algorithm for navigating a spider robot with four limbs (each
limb has four links) in a planar piecewise linear tunnel. The algorithm
continuously stabilizes the robot’s position by pushing its limbs against the
tunnel walls, while avoiding collision between the robot and the tunnel and
between the robot’s limbs. The research contribution of this thesis is the
combination of three research areas* (multi-limb walking mechanisms,
autonomous navigation,* and* stability of grasped objects) *into a
navigation algorithm for a spider robot.

The research includes investigation
of the robot’s environment from a grasping point of view, and determination of
the points on the tunnel walls where the robot can push its limbs against the
walls. A study of the robot’s environment from feasibility point of view while
taking into account the robot’s physical dimensions. A proposal for a naive
connectivity graph in which vertices represent feasible three-limb postures,
and shuffling legs along the tunnel walls are represented by the edges. A
proposal for a search algorithm in the naive connectivity graph. Last, we
propose a heuristic algorithm that converts the path from the *foothold-space*
as it represented in the naive connectivity graph to the robot’s *joint-space,
by* finding for each posture along the path a continuous joints trajectory in
the tunnel physical space. We propose a way to update the naïve
connectivity graph when the conversion fails by disconnecting edges and
removing vertices on the fly.

The work involves development of a C++ program that implements the proposed algorithm, and demonstration of the results in a three-dimensional graphical environment.