Planning and Navigation Where am I going How do I get there

1
Planning and NavigationWhere am I going? How do
I get there?
6
2
Configuration Space
6.2.1
3
Path Planning Overview
6.2.1

• 1. Road Map, Graph construction
• Identify a set of routes within the free space
• Where to put the nodes?
• Topology-based
• at distinctive locations
• Metric-based
• where features disappear or get visible

• 2. Cell decomposition
• Discriminate between free and occupied cells
• Where to put the cell boundaries?
• Topology- and metric-based
• where features disappear or get visible
• 3. Potential Field
• Imposing a mathematical function over the space

4
Visibility Graph
6.2.1
5
Voronoi Diagram
6.2.1
6
Voronoi, Sysquake Demo
6.2.1
7
Exact Cell Decomposition
6.2.1
8
Approximate Cell Decomposition
6.2.1
9
Adaptive Cell Decomposition
6.2.1
10
Path / Graph Search Strategies
6.2.1
11
Potential Field
6.2.1
12
Attractive Potential Field
6.2.1

• Parabolic function representing the Euclidean
  distance to the goal
• Attracting force converges linearly towards 0

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Repulsing Potential Field
6.2.1

• Barrier around the whole obstacle
• strong close to the obstacle
• no influence far from the obstacle
• minimum distance to the object
• Field tends to infinity as q gets closer to the
  object

14
Sysquake Demo
6.2.1
15
Extended Potential Field Method
6.2.1
Khatib and Chatila
16
Harmonic Potentials
6.2.1
17
Obstacle Avoidance
6.2.2
known obstacles (map)
observed obstacle
v(t), w(t)
Planed path
18
Bug Algorithm (Bug1)
6.2.2
19
Bug Algorithm (Bug2)
6.2.2
20
Vector Field Histogram (VFH)
6.2.2
Borenstein et al.
21
Vector Field Histogram (VFH)
6.2.2
Borenstein et al.
22
Video VFH
6.2.2
Borenstein et al.
23
Bubble Band Concept
6.2.2
Khatib and Chatila
24
Basic Curvature Velocity Methods (CVM)
6.2.2
Simmons et al.
25
Dynamic Window Approach
6.2.2
Fox and Burgard, Brock and Khatib
26
Global Dynamic Window Approach
6.2.2
27
Schlegel Approach
6.2.2
28
EPFL-ASL approach
6.2.2
29
EPFL-ASL approach
6.2.2
30
Comparison of Obstacle Avoidance Algorithms
6.2.2
Acrobat Document
31
Comparison of Obstacle Avoidance Algorithms
6.2.2
32
Comparison of Obstacle Avoidance Algorithms
6.2.2