AI Robotics
Chapter 5
Designing a Reactive Implementtation
MF15048
Yuki Takata
content
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Chapter Objective
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Designing a Reactive Implementation
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Summury
Chapter objectives
Use schema theory to design and program behaviors using object
oriented programming principles.
Design a complete behavioral system, including coordinating and
controlling multiple concurrent behaviors.
For a given behavioral system, draw a behavioral table specifying the
releasers, perceptual schemas, and motor schemas for each behavior.
Describe the two methods for assembling and coordinating primitive be
haviors within an abstract behavior: finite state automata and scripts. Be
able to represent a sequence of behaviors with a state diagram or with
a pseudocode script.
Build Reactive Behavior
Reactive behaviors
How to program more intelligence into the software
How to exploit better sensors than come with kits
http://education.lego.com/ja-jp/preschool-and-school/secondary/mindstorms-education-ev3
Deficis of robot programming
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Two deficits:
Designing behaviors tends to be an art, not a science
How to integrate a few well-designed and tested behaviors into a system?
Picking up and disposing of an empty soft drink can
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A series of behaviors
Search for a can
Search for the recycle bin
Move toward the can
Move toward the recycle bin
Pick up the can
Drop the can
It’s counterintuitive to think of these behaviors as being concurrent or merged.
Therefore, new techniques had to be introduced for controlling sequences of behaviors.
The schema structure is used recursively to simplify programming the control program.
Behaviors as Objects in OOP
Class
Schema
coordinated control program
Perceptual
Schema
Method
Motor
Schema
Behavior
Method
Perceptual
Schema
Motor
Schema
Behaviors as Objects in OOP
Primitive Behavior
Perceptual
Schema
Motor
Schema
Method
Method
Exsample
The steps in designing robot intelligence under the
Reactive Paradigm
1. Describe the task
2. Describe the robot
specfy and analys ecological niche
3. Describe the environment
4. Describe how the robot should act
in response to its environment
Design
5. Refine each behavior
6. Test each behavior independently
7. Test with other behaviors
Inplementation and test
Test system
1. Describe the task
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Specify whether to robot what to order to get good results
The first place consider that it is determined to describe
what is the purpose of the robot
In the casse of Colorado School of Mines team (CSM):It is the
task that the robot can travel along the curve, the road and sand
with a stationary obstacle.
2. Describe the robot
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Determine the limits and physical ability of the robot
In the case of CSM:
Foot robot in competition 3.5ft from 3ft, the power source
may carry themselves and calculation must be made onboard, in addition load of 20 pounds is applied to.
Omunibotto are mounted shaft encoder, steering motor, a
camcorder, a sonar. Rotation angle of it speed is a
processing capacity 33MHz at 22 ° is a slow accuracy of
emphasis and 1.5mph.
3. Describe the environment
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What perception whether the event is to instantiate a new
behavior. In how perceptual schema works, important to
establish positioning of the robot, a behavior of the
sensory opportunities.
In the case of CSM:
- Road width 10foot
- Gentle slope of grassland
· Competition time AM9: 00 ~ PM5: 00
- Sand the length of the 4feet
- Obstacles placed to leave the width of 4ft
4. Describe how the robot should
act in response to its environment
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What perception whether the event is to instantiate a new
behavior. In how perceptual schema works, important to
establish positioning of the robot, a behavior of the
sensory opportunities.
In the case of CSM:
follow-line behavior was suggested.
By recognizing the white line in the camera, and the
process proceeds while calculating the center between
the white lines.
5. Refine each behavior
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Establish a set of primitive behavior
Designers robot and "what to do" "How should be" would
be considered at the same time, but here we will focus on
what to do is.
In the case of CSM:
Because it had to react to white shoes and dandelion cotton
referee, or change the behavior itself, it was considered that
and add other behavior.
6. Test each behavior independently
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Although simulations are important for the evaluation of
performance simulation to model only the mechanism of a
robot, it is the only way to confirm the perception schema
by testing in a real situation.
7. Test with other behaviors
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In the case of CSM:
Although the test in white line of “follow-line” went well
added, because did not go well with white line and the
obstacle. obstacle to be a distortion of vision, a new
behavior “move-ahead" to ignore this . This is to use the
sonar as a trigger device.
Finite state automata
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Finite state automata (FSA) are a set of popular mechanisms
for specifying what a program should be doing at a given time
or circumstance
Summury
1. Describe the task
2. Describe the robot
3. Describe the environment
4. Describe how the robot should act
in response to its environment
5. Refine each behavior
6. Test each behavior independently
7. Test with other behaviors
Summury
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A behavior table serves as a means of
representing the component schemas and
functions of the behavioral system
Regardless of the implementation of the
coordination program , the control should rely
on the world to inform the robot as to what to
do next, rather than rely on the program to
remember and maintain state
Summury
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The designer must invest significant effort into developing
individual behaviors and into assembling them into a
sequence or an abstract behavior
Schema theory is highly compatible with Object Oriented
Programming
The behavior is derived from the schema class, if it had
been composed of a plurality of schemas, it must have the
adjustment control program