Application of Reactive Robotics with Subsumption Architecture

17.12.08 | Christoper Glenn Wulur | christoper.wulur@informatik 1

University of Hamburg Faculty of Mathematics, Informatics and Natural Science Department of Informatics Technical Aspects of Multimodal Systems

MIN Faculty Department of Informatics

Contents1. History2. Robot Architecture

a. Sense Planning Actb. Reactive Paradigmc. Comparison

3. Subsumption Architecture4. Study Case

a. Wander Robotb. Patrol Robotc. Multi Patrol Robot

5. Summary6. Reference

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History: Shakey● First general mobile purpose robot● Invented in Late 1960s● Based on Deliberate approach (Sense-Plan-Act, SPA)● Popular until late 1980s

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Source: [1]

Sense Planning Act

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Source: [6]

Problem with SPA● Planning may take some time● Environment may have changed while planning

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Reactive Paradigm● Vertical Decomposition● Each layer has access to sensors and

actuators● One layer is independent to each other● Key Concepts:

○ Situatedness○ Embodiment○ Intelligence○ Emergence

6Source: [6]

Reactive vs DeliberateReactive:

- Depends on reflexes- No internal state- World model not needed

Deliberate:

- Search through space of behaviors- Maintain Internal State

7Source: [2] Adapted. Source: [2] Adapted.

Subsumption Architecture● Introduced by Rodney Brooks● Levels of Competence:

○ Composes simple reactions(behaviors) that let one to take control at an appropriate time

● A Level can subsume lower levels○ Inhibition○ Suppression

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Study Case: Wander Robot

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Source: [4]

Wander Robot: Level 0

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Source: [6]

Wander Robot: Level 1

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Source: [6]

Wander Robot: Level 2

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Source: [6]

Study Case: Patrol Robot

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Source: [3]

Patrol Robot: Layers of Competence

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Source: [3]

Study Case: Multi Patrol Robot

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Source: [7]

Multi Patrol Robots: Layers of Competence

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Source: [7]

Summary● Subsumption Architecture:

○ Reactive approach○ Layer of Competences

■ Lower layer operates without presence of higher layer■ Higher layers may subsume and inhibit behaviors in lower layers

● Advantages○ Modularized behavior○ Extendability

● Disadvantages○ No Strategic planning○ No learnability

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Thank you for your attention

Questions?

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Reference[1] B. Siciliano, Springer handbook of robotics. Berlin: Springer, 2008, pp. 189-190.

[2] D. Floreano and C. Mattiussi, Bio-inspired artificial intelligence. Cambridge, Mass.: MIT Press, 2008, pp. 407-416.

[3] M. Li, X. Yi, Y. Wang, Z. Cai and Y. Zhang, "Subsumption model implemented on ROS for mobile robots", Annual IEEE Systems Conference (SysCon), 2016.

[4] R. Brooks, "Elephants don't play chess", Robotics and Autonomous Systems, vol. 6, no. 1-2, pp. 3-15, 1990.

[5] R. Brooks, "Intelligence Without Reason", Massachusetts Institute of Technology Artificial Intelligence Laboratory, 1991.

[6] R. Murphy, Introduction to AI robotics. London: The MIT Press, 2000, pp. 105-122.

[7] Z. GUO, W. YANG, M. LI, X. YI, Z. CAI and Y. WANG, "ALLIANCE-ROS: A Software Framework on ROS for Fault-Tolerant and Cooperative Mobile Robots", Chinese Journal of Electronics, vol. 27, no. 3, pp. 467-475, 2018.

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