Behavior Based Robotic

1. Amirkabir University of TechnologyComputer Engineering & Information Technology Department Behavior Based Robotic روباتیک رفتارگرا دکتر سعید شیری قیداری کتاب Behavior Based Robotic Ronald C. Arkin

2. مقدمه • Behavior-based roboticists argue that there is much that can be gained forrobotics through the study of neuroscience, psychology, and ethology. • • Neuroscience: the study of the nervous system's anatomy, physiology, biochemistry,and molecular biology. • • Psychology: the study of mind and behavior • • Ethology: the study of animal behavior in natural conditions • The behavior-based roboticist needs to decide how to use results from these • other disciplines. Some scientists attempt to implement these results as closely • as possibly, concerning themselves primarily with testing the underlying hypothesesof the biological models in question. Others choose to abstract the • underlying details and use these models for inspiration to create more intelligent • robots, unconcerned with any impact within the disciplines from whichthe original models arose. We will see examples of both approaches within this • book.

3. کنترل آگاهانه • Many different techniques and approaches for robotic control have been developed. • Figme 1.10 depicts a spectrum of current robot control strategies. The • left side represents methods that employ deliberative reasoning and the right • represents reactive control. A robot employing deliberative reasoning requires • relatively complete knowledge about the world and uses this knowledge to • predict the outcome of its actions, an ability that enables it to optimize its performance • relative to its model of the world. Deliberate reasoning often requires • strong assumptions about this world model, primarily that the knowledge upon • which reasoning is based is consistent, reliable, and certain. If the information • the reasoner uses is inaccurate or has changed since obtained, the outcome of • reasoning may err seriously. In a dynamic world, where objects may be moving • arbitrarily (e.g., in a battlefield or a crowded corridor), it is potentially dangerous • to rely on past information that may no longer be valid. Representational • world models are therefore generally constructed from both prior knowledge • about the environment and incoming sensor data in support of deliberation.

4. Deliberative reasoning systems often have several common characteristics: • They are hierarchical in structure with a clearly identifiable subdivision of • functionality, similar to the organization of commercial businesses or military • command. • • Communication and control occurs in a predictable and predetermined manner, • flowing up and down the hierarchy, with little if any lateral movement. • • Higher levels in the hierarchy provide subgoals for lower subordinate levels. • • Planning scope, both spatial and temporal, changes during descent in the • hierarchy. Time requirements are shorter and spatial considerations are more • local at the lower levels. • • They rely heavily on symbolic representation world models.

5. Reactive Systems • The right side of the spectrum depicted in figure 1.10 represents reactive systems. • Simply put, reactive control is a technique for tightly coupling perception • and action, typically in the context of motor behaviors, to produce timely • robotic response in dynamic and unstructured worlds. • We further define the following: • • An individual behavior: a stimulus/response pair for a given environmental • setting that is modulated by attention and detennined by intentio,n. • • Attention: prioritizes tasks and focuses sensory resources and is detennined • by the current environmental context . • • Intention: determines which set of behaviors should be active based on the • robotic agent's internal goals and objectives . • • Overt or emergent behavior: the global behavior of the robot or organism as • a consequence of the interaction of the active individual behavior

6. سیستم های واکنشی • این سیستمها ارتباط مستقیمی بین ادارک و عمل برقرار میکنند بدون اینکه به سابقه و یا ارتباط بین اطلاعات توجهی نمایند. • خصوصیات عمده آنها بصورت زیر است: • رفتارها عموما ساده بوده و از نوع sensorimotor هستند بدین معنا که