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Computation and Design of Autonomous Intelligent Systems Robert L. Fry Presentation to the SPIE Defense and Security Conference Orlando, FL March 17, 2008 This work was supported through AFOSR contract FA9550-06-1-0297 under Dr. Robert Bonneau

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Page 1: SPIE Conference V3.0

Computation and Design of

Autonomous Intelligent

Systems

Robert L. Fry

Presentation to the SPIE Defense and Security Conference

Orlando, FL

March 17, 2008

This work was supported through AFOSR contract FA9550-06-1-0297 under Dr. Robert Bonneau

Page 2: SPIE Conference V3.0

Outline

• Computational Theory of Autonomous Intelligent Systems

• Engineering intelligent Systems

• Neural Computation and other Sample Applications

• Discussion and Next Steps

Page 3: SPIE Conference V3.0

Computational Theory of

Autonomous Intelligent Systems

Page 4: SPIE Conference V3.0

Basic Idea

To engineer an intelligent system, one must have a working definition for what intelligence is. The following is suggested:

“An intelligent system acquires information and uses it to make decisions in service to its computational goal”

If we can computationally quantify each of the

above highlighted terms, then we might have a

formal basis for engineering intelligent systems.

Page 5: SPIE Conference V3.0

Definition Flowdown

To acquire information, a system must pose a question to its environment

To make decisions, a system must answer a question of what to do.

Page 6: SPIE Conference V3.0

What is a Question?

What is a Question?

If we can come up with a working

definition of questions, then we are in

business.

Page 7: SPIE Conference V3.0

“What Is a Question?”

“A question is defined by the set of

all subjectively possible answers”

Richard Cox, Physicist

Johns Hopkins University

(1898-1991)

Dr. Richard Cox1 of the Johns Hopkins

University Physics Department

developed a joint algebra of questions

and assertions

1 “Of Inference and Inquiry,” Proc. First Maximum Entropy Workshop, MIT, 1978

His extension of logic mathematically captures how

computation is performed within the subjective

frame of a system.

Page 8: SPIE Conference V3.0

Boolean Algebra of Questions and Assertions

~~a = a

a a = a a a = a

a b = b a a b = b a

~(a b) = ~a ~b ~(a b) = ~a ~b

a b c = a (b c)

= (a b) c

a b c = a (b c)

= (a b) c

(a b) c = (a c) (b

c)

(a b) c = (a c) (b

c)(a b) b = b (a b) b = b

(a ~a) b = b (a ~a) b = b

a ~a b = a ~a a ~a b = a ~a

Algebra AssertionsAlgebra Assertions

~~A = A

A A = A A A = A

A B = B A A B = B A

~(A B) = ~A ~B ~(A B) = ~A ~B

A B C = A (B C)

= (A B) C

A B C = A (B C)

= (A B) C

(A B) C = (A C)

(B C)

(A B) C = (A C) (B

C)(A B) B = B (A B) B = B

(A ~A) B = B (A ~A) B = B

A ~A B = A ~A A ~A B = A ~A

Algebra of QuestionsAlgebra of Questions

Logical Basis of

Probability Theory

Logical Basis of

Information/Control

Theories

• Logical questions quantify the computational rules of intelligence and autonomy

Dual Boolean Algebras

Conventional

Logic

Logic of

Questions

Let upper case italicized letters like A denote questions,

e.g., A “Is it an apple or not?” {a, ~a}.

Page 9: SPIE Conference V3.0

Probability and Entropy

Property Probability Theory Bearing Theory

(Entropy)

Conjunctive Rule p(ab|c)=p(a|c)+p(b|c)p(ab|c) b(AB|C)=b(A|C)+b(B|C)b(AB|C)

Normalization p(a|c)+p(~a|c) = 1 b(A|C)+b(~A|C) = 1

Marginalization Rule p(ab|c)+p(a~b|c)=p(a|c) b(AB|C)+b(A~B|C)=b(A|C)

Bayes’ Theorem p(ab|c)=p(b|c)p(a|cb) b(AB|C)=b(B|C)b(A|CB)

• Probability and Entropy (called Bearing) are derivable from logic and

consistency • Respectively they are the unique measures of subjective knowledge

and uncertainty as computed within a local system frame

Sample Identities in probability and information theory

Page 10: SPIE Conference V3.0

A Simple “Intelligent” System

Decision Space Answer

Y: Cilia turned On or Off

Cilia

A protozoan-like

system asks X and

answers Y

Creatures

Optical Field-of-

View

Currents randomly perturb

creatures orientation

Information Space Ask X: Detector is On or Off

Light Source

and Possible

Food

Linear

Motion

Detector

There are two kinds of questions – those that can be asked and those that can be answered by a system.

Page 11: SPIE Conference V3.0

Logical Questions: Card-Guessing Game Example

S{ , , , } C{ } ,

S“What Suit is the Card?” C“What Color is the Card?”

For systems acquiring information X and making decisions

Y, and so X Y is the actionable information of the system.

Define the Questions S and C:

Disjunction (Logical OR) provides the information asked by either

S C { , , } , , , { } , C

Conjunction (Logical AND) provides the information asked by both

SC { ■ , ■, ■ , ■, ■ , ■, ■ , ■}

{ , , , } S

Page 12: SPIE Conference V3.0

Decision Space Y:

Cilia turned On or

Off

Cilia

Information Space X: Detector is On or Off

Detector

Intelligence and Autonomy

x=0 y=0

x=1 y=0

Never Do

Anything

x=0 y=1

x=1 y=1

Always Do

Something

x=0 y=1

x=1 y=0

Always Do Wrong

Thing

Possible Behaviors

Four computational mappings

comprise possible system

behaviors. The last matches

decisions to available

information and so XY =X =Y

x=0 y=0

x=1 y=1

Always Do Right

Thing

XY=X

Page 13: SPIE Conference V3.0

Engineering Intelligent

Systems

Page 14: SPIE Conference V3.0

Intelligence and Computation

Thermodynamics

Intelligence Information

Theory

Computation

and

Questions

Theory exploits and extends

concepts and tools from

thermodynamics and

information theory and in

turn enriches them.

• Entropy

• Source and channel coding

• Shannon’s dual problems

• *Dual-matching concept

• Entropy

• Maximum entropy principle

• Shannon’s dual problems

• Carnot cycle

• Dual-matching

• *Carnot cycle

• Maximum entropy principle

• Entropy

Page 15: SPIE Conference V3.0

Critical Domain Concepts

Thermodynamics

Intelligence Information

Theory

Computation

and

Questions

Carnot Cycle from Thermodynamics and Dual-

Matching from Information Th. are especially important

to intelligent systems

Carnot Cycle

Dual-

Matching

Page 16: SPIE Conference V3.0

Information Theory and Intelligence

Source X Receiver Y

Answer question of what

to transmit

Question answered as to

what is received

Information Theory

Decisions Y Acquire X

Question posed to

environment answered

Question answered as

to what to do

Intelligence Theory

• Information theory and intelligence theory are functional duals

• Latter describes how to make decisions with uncertainty

• Methods and constructs in one domain apply to the other

Page 17: SPIE Conference V3.0

Dual-Matching Concept

• Just as the Carnot cycle from Thermo applies to intelligent systems, so does the recent concept2 of Dual-Matching from information theory

• Dual-matching provides the quantitative basis for the design and operation of efficient intelligent systems (their Carnot Cycles)

• Dual-matching requires simultaneously solving Shannon’s dual problems:

– Minimize information required

– Maximize what can be done with acquired information

2 M. Gastpar, To Code or Not to Code, Ph. D dissertation, Thèse EPFL, no 2687, Ecole

Polytechnique Fédérale de Lausanne, 2002. This concept is revolutionizing information theory.

Page 18: SPIE Conference V3.0

Computation and Carnot Cycles

4. Erase Information

2. Store Information

3. Make Decision

1. Acquire Information 1. Make Decision

3.0 Acquire Information

4. Store Information

2. Erase Information

• Carnot engine

• Internal combustion engine

• Communication systems

Area = Useful Work

Produced

Area = Energy

Required to Operate

• Carnot refrigerator

• Computer contol

• Intelligent systems

• Logic dictates that there are two kinds of computation a

system can perform

• These correspond to the two Carnot Cycles of

thermodynamics

Page 19: SPIE Conference V3.0

Sample Applications

Page 20: SPIE Conference V3.0

Neural Computation

Using the described theory and methods, one

can perform a top-down design of pyramidal

neurons as found in brains. This is a simple,

elegant, and informative example.

Page 21: SPIE Conference V3.0

What Do Neurons Ask and Answer?

Axon

Comprises

Single

Output

Y={0,1}

X1

X2

X10000

104 Synaptic

Inputs Xi={0,1}

Soma Integrates

Inputs and Makes

Decisions

• There are 210000 possible

answers (microstates)!

• The neuron poses the

question X=X1X2…X10000

• Neuron simply answers Y

Assume matching of

actionable information

to decisions is its goal:

XY = Y.

Page 22: SPIE Conference V3.0

Principal of Maximum Entropy

• The Principal of Maximum Entropy basic to

thermodynamics dictates neural probability distribution

Resulting Max-Ent Distribution

Partition (normalization)

Function

0

p( , | ) ln p( , | )

p( , | )[( , ) , ]

p( , | )[ ]

p( , | ) 1

y Y X

T

y Y X

y Y X

y Y X

J y a y a

y a y y

y a y y

y a

x

x

x

x

x x

x x x

x

x

exp ( , )p( , )

T y yy

Z

xx

exp ( , )TZ y y

x y

x

• Lagrange multiplier is coupling strengths and scalar

is somatic decision threshold

Page 23: SPIE Conference V3.0

Dual-Matching Adaptation

Hebbian Gating

for (1) – (3)

.

.

.

1

1

n

Y

X1

X2

Xn

.

.

.

1

n

X

Y

Three Hebbian Learning Equilibria Result that Can be

Realized Using Simple Biologically Plausible Algorithms

1) Threshold Adaptation () The Optimal Decision Threshold Is

Average Somatic Potential

( ) (1 ) ( )t t t T

x

3) Delay Equalization () Elements of the Optimal Time Delay

Vector Must Satisfy “Momentum”

Equalization:

di / dt = i y(t) dxi(ti)/dt = 0

2) Gain Adaptation ()

The Optimal Gain Vector Is the Largest

Eigenvector of the Input Covariance Matrix R

( ) ( ) ( )[ ( ) ( ) ( )]t t t t tx x x

| 1 | 1T

E y y x x x xR( )

Page 24: SPIE Conference V3.0

Neural Carnot Cycle

4. Erase Information

during the refractory

period

3. Decision Made

by soma

0.9 Bit/Decision

T=1/

1. Acquire Information

through synapses

2. Information

Stored in

soma

T=1

T=0.2

H(X)=b(X|A)

Z=2n

I(X;Y)=b(XY|A)

Z=2n+1

Z=2n Z: 2n2n+1

A single neuron operates as a Carnot refrigerator as do

all intelligent systems. It has ~90% Carnot Efficiency.

Tem

pera

ture

Entropy

Page 25: SPIE Conference V3.0

Simulation of Neural

Computational Model

Page 26: SPIE Conference V3.0

Modeling and Simulation Training Set

Training Vector Bit

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

1 1 1 1 1 0 1 1 0 1 0 0 0 1 1 0 1 1 0 0 1

2 0 1 0 0 0 1 0 0 0 0 0 1 1 1 0 1 1 1 0 1

3 1 1 0 1 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 1

4 1 1 1 1 0 1 1 0 1 0 0 0 1 0 0 1 1 0 0 1

5 1 1 1 1 0 1 1 0 1 0 0 0 1 1 0 1 1 0 0 1

6 1 1 1 1 1 0 1 0 0 0 1 0 0 0 0 0 1 0 0 1

7 0 1 0 1 0 1 1 0 1 0 0 0 0 1 0 1 1 0 0 1

8 1 1 1 1 0 1 1 0 1 0 0 0 1 0 0 1 1 0 0 1

9 1 1 1 1 0 1 1 0 1 0 0 0 1 1 0 1 1 0 0 1

10 1 0 0 1 0 0 0 1 1 0 1 1 1 1 0 1 1 0 0 1

11 1 1 0 0 0 1 1 0 0 0 0 0 0 1 0 0 1 0 1 1

12 1 1 1 1 0 1 1 0 1 0 0 0 1 0 0 1 1 0 0 1

13 1 1 1 1 0 1 1 0 1 0 0 0 1 1 0 1 1 0 0 1

14 1 0 0 0 1 1 1 0 1 0 1 1 0 0 1 1 1 1 0 1

15 0 0 0 0 1 1 1 1 0 0 1 0 1 0 1 0 0 1 1 1

16 1 1 1 1 0 1 1 0 1 0 0 0 1 0 0 1 1 0 0 1

17 0 1 1 0 1 1 1 0 0 0 1 1 1 1 0 1 0 0 1 1

18 1 0 0 0 0 0 1 0 0 0 1 0 1 1 1 1 0 1 1 1

19 1 0 0 1 0 0 0 1 0 0 0 1 0 0 0 0 1 1 1 1

Vecto

r I

nd

ex

20 1 1 0 1 0 1 0 0 1 0 1 0 0 0 0 0 0 0 0 1

Page 27: SPIE Conference V3.0

Hamming Distance Between

Vectors Conveys Structure

Code Number

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

1 0 7 10 1 0 7 3 1 0 7 6 1 0 10 20 1 8 10 12 7

2 7 0 11 8 7 12 6 8 7 8 7 8 7 9 13 8 7 9 9 10

3 10 11 0 9 10 7 9 9 10 9 8 9 10 12 10 9 14 10 6 5

4 1 8 9 0 1 6 4 0 1 8 7 0 1 9 19 0 9 11 11 6

5 0 7 10 1 0 7 3 1 0 7 6 1 0 10 20 1 8 10 12 7

6 7 12 7 6 7 0 8 6 7 10 7 6 7 9 13 6 9 11 9 6

7 3 6 9 4 3 8 0 4 3 8 5 4 3 9 17 4 9 11 11 6

8 1 8 9 0 1 6 4 0 1 8 7 0 1 9 19 0 9 11 11 6

9 0 7 10 1 0 7 3 1 0 7 6 1 0 10 20 1 8 10 12 7

10 7 8 9 8 7 10 8 8 7 0 11 8 7 9 13 8 11 9 7 8

11 6 7 8 7 6 7 5 7 6 11 0 7 6 10 14 7 8 8 8 7

12 1 8 9 0 1 6 4 0 1 8 7 0 1 9 19 0 9 11 11 6

13 0 7 10 1 0 7 3 1 0 7 6 1 0 10 20 1 8 10 12 7

14 10 9 12 9 10 9 9 9 10 9 10 9 10 0 10 9 10 8 10 9

15 20 13 10 19 20 13 17 19 20 13 14 19 20 10 0 19 12 10 8 13

16 1 8 9 0 1 6 4 0 1 8 7 0 1 9 19 0 9 11 11 6

17 8 7 14 9 8 9 9 9 8 11 8 9 8 10 12 9 0 8 14 11

18 10 9 10 11 10 11 11 11 10 9 8 11 10 8 10 11 8 0 10 11

19 12 9 6 11 12 9 11 11 12 7 8 11 12 10 8 11 14 10 0 9

Co

de

Nu

mb

er

20 7 10 5 6 7 6 6 6 7 8 7 6 7 9 13 6 11 11 9 0

Figure 5.4: Hamming distances between the 20 codes listed in Table 5.1.

Page 28: SPIE Conference V3.0

Simulation Output

Synaptic Gains

1 5 10 15 20 -0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

Gains on non-informative

inputs are driven to zero.

Training vector bit

Vectors Inducing

Firing

1 5 10 15 20 0

1

The neuron learns to fire

on almost exactly half of

the training vectors.

Training vector index

Page 29: SPIE Conference V3.0

7/18/2002

A Geometric View of Neural Computation

Input Information Space

contains >210000 codes

Neuron defines a

hyperplane

decision surface

Tx– = 0

Hyperplane Separates

Input Space into Two

Equally Probable

Regions: H(Y) = 1 bit

Fire!

(y = 1)

Do Not Fire!

(y = 0)

Theory provides a detailed

explanation of how

pyramidal neurons compute

Page 30: SPIE Conference V3.0

Weapon System Applications

Page 31: SPIE Conference V3.0

Weapon Systems and Dual-Matching

• Efficient system operation requires continual matching of weapon system information and control spaces

• Fire Control Loop operates as an engine governor

– Minimize fuel consumption under varying loading conditions

• All weapon systems acquire information and make decisions with uncertainty

• The fire control loop of a missile system is a good example:

Dual-Matching Process

X = Where can the target be? (Informational uncertainty)

Y= Where can the weapon go? (System control capacity)

X

Y

Page 32: SPIE Conference V3.0

Weapon System Applications

• Algorithms Proposed or Under Development* – *Object correlation

– Sensor management

– *Discrimination and track fusion

– *Weapon-Target assignment

– *Guidance Laws1

• Weapon System Architectures – Distributed fire control for swarming intelligence

– C2BMC

– Networked weapon systems have unique Boolean expressions

1 Example of the derivation of a guidance law with uncertainties in tracking, discrimination,

and guidance is given in the backup slides and a paper is available on request.

Page 33: SPIE Conference V3.0

Discussion and Next Steps

• Continue to model for biological computation emphasizing the development of Cortical Systems

• Begin wider formulations of weapon systems problems with focus on ballistic missile defense

– Decisioning uncertainty is hallmark of the BMD problem

• Military and data networks have simple formulations

– Networks have natural functional decompositions lending themselves to global optimization

Page 34: SPIE Conference V3.0

Main issues in going forward?

• Documenting work done so far - perhaps in book form

• Bridging the multidisciplinary boundaries of thermodynamics, information theory, and intelligence

– Only a modest understanding of each area seems sufficient

Page 35: SPIE Conference V3.0

Acknowledgements

• This work was supported by AFOSR Project IONS - Information-Theoretic Optimization of Networked Systems

• Project IONS is 3-Year joint SEG/Princeton project to develop an engineering framework for distributed intelligent systems

• My co-PI is Dr. Mung Chiang of Princeton who has developed a highly efficient information optimization methods based on Geometric Programmingg

Page 36: SPIE Conference V3.0

Selected References

[1] “Double Matching: The Problem that Neurons Solve,” Computational Neuroscience Meeting, Neurocomputing, 69, pp. 1086–1090, 2005.

[2] “Neural Statics and Dynamics,” Computational Neuroscience Meeting, Neurocomputing, 65, pp. 455-462, 2005.

[3] “Logical and Geometric Inquiry,” Proc. Workshop on Maximum Entropy and Bayesian Methods, 659, pp. 243-280, 2003, American Institute of Physics.

[4] “A Theory of Neural Computation,” Computational Neuroscience Meeting Neurocomputing, 52, pp. 255-263, 2002.

[5] “Neural processing of information,” Proc. International Symposium on Information Theory, Trondheim, Norway, pp. 217, 1994.

[6] “Cybernetic Defense Systems,” Proc. of the MD SEA Conference held in Monterey, CA, February 2001.

[7] et. al A Fokker-Planck Model For A Two-Body Problem, Proc. Maximum Entropy and Bayesian Methods, 617, pp. 340-371, 2002.

[8] “Cybernetic systems based on inductive logic,” 2000 Maximum Entropy and Bayesian Methods Conference, Gif sur Yvette, France

[9] “Constructive methods for BMD algorithm design and adaptation,” Phase III of the Battlespace Study Final Report, JHU/APL, 2000.

[10] “Multi-sensor fusion using information geometry,” presented at the 1999 Maximum Entropy and Bayesian Methods Conference, Boise, Idaho.

[11] “Transmission and transduction of information,” Presented at the Workshop on Maximum Entropy and Bayesian Methods, Garching, Germany, 1998.

[12] “An analytical basis for TBMD system design,” Proc. 1998 National Fire Control Conference, San Diego, CA.

[13] “Observer-participant models of neural processing,” IEEE Trans. Neural Networks, 6, pp. 918-928, July, 1995.

Page 37: SPIE Conference V3.0

Backup Slides

Page 38: SPIE Conference V3.0

A Neuron is an Intelligent System

• Synapses X and axon Y are elementary questions

• Laboratory confirmation of predicted energy allocations

• Significant numbers of biological results and predictions

• Partition function and critical temperature determined

Axon Y

(Output)

Soma

(Decides)

H(Y)

I(X;Y)

~104 Dendritic Inputs

and 1 Output

Theory provides a detailed

explanation of how

pyramidal neurons compute

, , 1

0( ) ( , ) log ( , ) { } { }( | )

( )

n

i i

X Y X Y i

J p y p y E x y E yp y

p y

λ x xx

Page 39: SPIE Conference V3.0

Midcourse BMD Example

• Perform a distributed computation to achieve global optimization

• Dynamically match actionable information X and decision space Y

Distributed C2BMC

Dual-Matching

Algorithms

Sensor measurements eliminate possible

target locations

Question X “Where is the target?”

Sensing

Elements

Radars

Seekers

Guidance decisions eliminate possible places

missile can go

Question Y “Where should I go?”

Kinematic

Elements

Boosters

KVs

Page 40: SPIE Conference V3.0

BMD System Architectures • Weapon architectures can be quantified

• Basis for comparing architectures and making trades

• Decomposition allows representation of entire network

• Formulation applies to any kind of weapon or warfare:

I. 1-on-1 I(X;Y) Single KV vs. Single RV (EKV)

II. M-on-1 I(X;Y1,Y2, …,Y) Multiple KVs vs. Single RV (MKV)

III. 1-on-N I(X1,X2,…,XN;Y) Single KV vs. MIRVed Threat

IV. M-on-N I(X1,X2,…,XN;Y1,Y2, …,YM) Multiple KVs vs. MIRVed Threat

Architectural

Class

Basic Objective

Function BMD Architecture

Bullets = KVs = Infantry = Missiles

Page 41: SPIE Conference V3.0

Guidance with Targeting and Guidance Uncertainties

Will now determine the exact analytical solution to a simple 1-

dimensional problem to demonstrate some of the described

concepts.

Tracks will never be perfect, but this does

not change how the problem is solved.

X

x0

x1

Target Localization

Space Target localization with perfect tracks at x0 and x1

and resp. discrimination probabilities p0 and p1.

respectively (p0+p1=1):

p(x) = p0(x-x0) + p1(x-x1)

This is where the target can be

Page 42: SPIE Conference V3.0

MKV Architectures

Y1 Y2 Ym

X1 X2 Xm

. . .

a) Federated architecture

Y1 Y2 Ym

X1 X2 Xm

. . .

b) Swarming architecture

(Only nearest-neighbor comm)

Z2

Z1

Z3

Z2

Zm

Zm-1

Y1 Y2 Ym

X1 X2Xm. . .

c) Centralized control architecture

ZmZ2Z1

XC

I1(X;Y)

I3(X;Y)

I2(X;Y)

Potential to trade system architecture vs.

weapon system capacity vs. cost

Weapon System

Capacity

Cost ($)

A1 A3

A2

A1 A2 A3

Page 43: SPIE Conference V3.0

Guidance with Targeting and Guidance Uncertainties

Can determine optimal guidance solutions in the

presence of tracking, discrimination, and guidance

uncertainties

X

x0

x1

Target localization with perfect tracks at x0 and x1

and resp. discrimination probabilities p0 and p1.

respectively (p0+p1=1):

Tracks will never be perfect, but this does

not change how the problem is solved.

Target Localization

Space

0 0 1 1( ) ( )p x x p x x

Page 44: SPIE Conference V3.0

Guidance with Targeting and Guidance Uncertainties

The kinematic space of the system is the reachable space of

the interceptor after it selected some point as its next guide

point – the missile always has to be going somewhere!

Y

x0

x1

Missile Kinematic

Space (After Maneuver)

The guidance algorithm objective is to

determine the optimal as its next guide point

given guidance and informational uncertainties

of p(y|x) and p(x).

Varying changes the kinematic space p(y|x)

once the command is executed.

2

2

( )

2( | ) ( )

y

p y x y x e

Page 45: SPIE Conference V3.0

Guidance with Targeting and

Guidance Uncertainties

The idea is to minimize the mutual information over subject to

a probability-of-miss constraint (a “miss” is like a transmission

bit error):

This guidance law minimizes statistically the fuel expenditure over

the ensemble of such engagements with these uncertainties.

( , ) I( ; | ) 1 ( )J X Y p y d where

,~

( | )I( , ) ( ) ( | ) log

( )Y y yX

p y xX Y dx p x p y x

p y

If no constraint, then J0 and the missile guides halfway between

the objects if both will remain in its kinematic space:

* 0 1

2

x x

Otherwise the missile should navigate to the probability centroid

between the objects:

*

0 0 1 1p x p x

Page 46: SPIE Conference V3.0

Guidance with Targeting and Guidance Uncertainties

The kinematic space of the system is the reachable space of

the interceptor after it selected some point as its next guide

point – the missile always has to be going somewhere!

Y

x0

x1

Missile Kinematic

Space (After Maneuver)

’’

The guidance algorithm objective is to

determine the optimal as its next guide point

given guidance and informational uncertainties

of p(y|x) and p(x).

Initially assume that missile is guiding half way

between the objects (x0+x1)/2 implying that

discrimination information is not used.

(x0+x1)/2

2

2

( )

2( | ) ( )

y

p y x y x e

(Probability missile can get to y when target is at x)

Page 47: SPIE Conference V3.0

Guidance with Targeting and

Guidance Uncertainties

The idea is to minimize the mutual information over subject to

a probability-of-miss constraint (a “miss” is like a transmission

bit error):

( , ) I( ; | ) 1 ( )J X Y p y d If no constraint, then J0 and the missile continues guiding

halfway between the objects:

* 0 1

2

x x

x0 = 0

x1 = 1

p0=0.25

p1=0.75

2=1

Example

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0

0.005

0.01

0.015

0.02

0.025

0.03

mu

Tra

nsacte

d C

ontr

ol (b

its)

Control Rate vs.

Guide Point

Targeting

information ignored

Guide to most

probable target.

This minimizes

probability of

error but not fuel.

PIP

Page 48: SPIE Conference V3.0

x0=0, x1=1, p0=p1=0.5

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.94

0.945

0.95

0.955

0.96

0.965

0.97

0.975

Guide Point mu

Pro

ba

bility o

f H

it

=2.0

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.8

0.81

0.82

0.83

0.84

0.85

0.86

0.87

0.88

0.89

Guide Point mu

Pro

ba

bility o

f H

it

=1.0

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

0.57

0.575

0.58

0.585

0.59

0.595

0.6

0.605

0.61

0.615

Guide Point mu

Pro

ba

bility o

f H

it

=0.5

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.45

0.46

0.47

0.48

0.49

0.5

0.51

0.52

0.53

0.54

Guide Point mu

Pro

ba

bility o

f H

it

=0.4

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Guide Point mu

Pro

ba

bility o

f H

it

=0.2

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

Guide Point mu

Pro

ba

bility o

f H

it

=0.1

Evolution of PIP During Homing for Minimized Probability of Error

Centered PIP Broadened PIP

Begin Object

Commit

Object

Committed To

Object

Committed To

Centered PIP

Page 49: SPIE Conference V3.0

Cortical Model

. . .

. . .

. . .

. . .

. . .

. . .

. . .

Y1 Y2 Y3 Ym

X1 X2 Xn

. . .

Pyramidal neurons (Gibbs Sampler) elements

Cortices consist of a collection of pyramidal neurons whose properties

are now well established

• Contains m pyramidal neurons

and has n inputs

• Full connectivity is unnecessary

and in general is sparse

Page 50: SPIE Conference V3.0

Cortical Hamiltonian

1

1 1

m

i

i

n m

i ij j ik k i i

j k

H H

H x y y

Since energy is an extensive property of a system, the cortical

Hamiltonian is just the sum of the constituent single-neuron

Hamiltonians:

Network must then have a well-defined Boltzmann distribution:

exp ( , )( , )

H x yp x y

Z

By way of analogy with statistical physics, all network

macroscopic properties are defined including Free Energies,

entropies such as H(X,Y), and most importantly, mutual

information.

Page 51: SPIE Conference V3.0

Cortical Circuit WTA Computation

. . .

. . .

. . .

. . .

. . .

. . .

. . . • K credible targets with N = 1 true but unknown target

• M bullets (KVs)

• Neurons or Gibbs Sampling Elements

Y1 Y2 Y3 YM

X1

X2

XK

• Network determines optimal p(y|x) to

min I(X;Y) subj. to constraints

• Connectivity requirements driven by

need to be able to stabilize to

asymptotic distribution

• Output is probabilistic assignment

which is desirable from guidance

perspective

• Local nodes are identical IT-neurons

where local=global objective function

optimization

• Network has partition function and

likely critical temperatures

• Gibbs () and Helmholtz () Free

energies ( Saddle Points)

• Network Hamiltonian:

Discrimination Information p(xk) 1 1 1

K M MT T

ik ik ik ik ik ik ik ik

k i i

H y y y

λ x ν y

Page 52: SPIE Conference V3.0

A grasshopper stealthily evades the photographer over a 30-second sequence of frames

Page 53: SPIE Conference V3.0

Example of the Implication of Assertions

Define the subjective inquiry B “Is it a Boy?”

Then let b “It is a Boy!” and s “It Is My Son!”

s b =

=

If Asserted … Then Known …

• If “It is My Son!” is Asserted, then this Additional Information is

Erased by B

• Implication means that if b answers the question B, then so does s

Holds Only Relative

to Question B

Page 54: SPIE Conference V3.0

Theory Summary

• Distinguishability gives rise to Boolean Algebras – Exhaustion and Mutual

Exclusion Together Yield Complementarity

• Logical implication is the natural relational operator for questions and assertions

• Probability and Entropy are the corresponding natural subjective measures of degrees of implication

“Nothing”

Assertions Questions

Probability

Theory

Information

Theory

Intelligent

Systems

System Distinguishes

Boolean

Algebra and

Logical

Implication

Induce Computational Rules and Natural

Measures of Probability and Entropy