Quantum Robot for Teenagers

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Quantum Robot for Teenagers

• Arushi Raghuvanshi
• Yale Fan
• Michal Woyke
• Marek Perkowski

Presentation at ISMVL 2007 May 14-16
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Outline

• 1. Introduction to Braitenberg Vehicles
• 2. Programmable Braitenberg Vehicles
• 3. Combinational and Quantum Circuits
• 4. Deterministic, Probabilistic, and Entangled
  Behaviors
• 6. Examples or our Robots
• 7. Next steps

3
Classic Braitenberg
Fear
Aggression
4
Programmable Braitenberg
Ultrasonic Sensor
A Left Light Sensor
B Right Light Sensor
Circuit Implemented by Program
Q Motor for Right Wheel
P Motor for Left Wheel
Sound/Touch Sensor
5
Representing Gates via Matrices
A B P Q Behavior
0 0 0 0 Robot stays stationary.
0 1 0 1 Robot moves left.
1 0 1 1 Robot moves forward.
1 1 1 0 Robot moves right.
Input
Output
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Using Binary Gates
Feynman Gate
And-OR Gates
A
A
P
P
Q
Q
B
B
A B P Q Behavior
0 0 0 0 Robot stays stationary.
0 1 0 1 Robot moves left.
1 0 1 1 Robot moves forward.
1 1 1 0 Robot moves right.
A B P Q Behavior
0 0 0 0 Robot stays stationary.
0 1 0 1 Robot moves left.
1 0 0 1 Robot moves left.
1 1 1 1 Robot moves forward.
This behavior is deterministic because it can be
determined how the robot will react to a given
input.
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Using Quantum Gates
Hadamard
Hadamard
Input A0
Output
A

P
H
X
Which in Dirac Notation is,
Which after Measurement means,
A P Behavior
0 ½ 0 ½ 1 Motor stops or moves.
1 ½ 0 ½ 1 Motor stops or moves.
½ probability of 0 ½ probability of 1
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Entanglement Example
H
P
A
Q
B
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Entanglement Example Step 1
Hadamard in parallel with wire
Hadamard
A
P
H
A
P
H
Q
B
A P Behavior
0 ½ 0 ½ 1 Motor stops or moves.
1 ½ 0 ½ 1 Motor stops or moves.

?
A B P Q Behavior
0 0 0 1 0 0 Robot stays stationary. Or, moves tight
0 1 0 1 1 1 Robot moves left. Or, moves forward
1 0 0 1 0 0 Robot stays stationary. Or, moves tight
1 1 0 1 1 1 Robot moves left. Or, moves forward
Wire
A
P
A P Behavior
0 0 Stopped
1 1 Moving
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Entanglement Example Step 2
Einstein-Podolsky-Rosen
Feynman Gate
A
P
H
A
Q
P
B
Q
B

X
A B P Q Behavior
0 0 ½ 0 ½ 1 ½ 0 ½ 1 Stationary or moves forward.
0 1 ½ 0 ½ 1 ½ 1 ½ 0 Turns left or turns right.
1 0 ½ 0 ½ 1 ½ 0 ½ 1 Stationary or moves forward.
1 1 ½ 0 ½ 1 ½ 1 ½ 0 Turns left or turns right.
A B P Q Behavior
0 0 0 0 Robot stays stationary.
0 1 0 1 Robot moves left.
1 0 1 1 Robot moves forward.
1 1 1 0 Robot moves right.
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Putting it together
Vector I
A B
False False
False True
True False
True True
0 1 0 0
Selected Combination
A
B
H
Matrix M
P
Q
Measurement
P Q
False False
False True
True False
True True
Vector O
0 1 1 0
Either the robot will turn left or turn right
with equal probability.
O M I
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RobotC Program Walkthrough
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Braitenberg Demo
Lightsensors
Ultrasonic Sensor
Avoids Light
Feynman Gate
P
Q
But.. destroys objects that emit light
Avoids Objects
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Braitenberg Demo
Lightsensors
Ultrasonic Sensor
Goes towards light but turns away before hitting
P
Q
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Braitenberg Demo
Soundsensor
Ultrasonic Sensor
Avoids Obstacles
P
Q
But.. Hits obstacles when Music is playing
Dances with Music
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Quantum Potato Head
Happy Face
Sad Face
Confused Face
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Quantum Potato HeadBehavior using
Einstein-Podolsky-Rosen Circuit
Response to Touch
Response to both Light and Touch
Response to Light
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Old Duck Biped
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Next Quantum Automaton Robot
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Key Learnings

• We learned
• About Braitenberg Vehicles
• How to program robots to demonstrate
  probabilistic, deterministic, and entangled
  behavior
• About quantum theory and quantum computing
• How to represent circuits with matrices
• Programming Robots in C language
• Trigonometry, complex numbers, matrix and vector
  multiplication, and digital circuits.

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Backup
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Video
Placeholder

• Link to video (5-8 minutes)
• Video of Quantum Potato head (show Feynman, EPR)
• Video of Braitenberg Vehicle (show Feynman, EPR)

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Selected Circuits
Feynman Gate
Direct Connection
Swap Gate
A
A
A
P
P
P
Q
Q
Q
B
B
B
Identity Matrix
FeynmanSwap
Einstein-Podolsky-Rosen
And-OR Gates
A
A
P
P
Q
Q
B
B
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Robot Configuration Additional Sensors
Sound Sensor
Left Light Sensor
Ultrasonic Sensor
Right Light Sensor
Touch Sensor
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Selected Configurations

• Configuration 1 (classic)
• A Left Light Sensor
• B Right Light Sensor
• Configuration 2 (light distance)
• A True, if the sum of both light sensor values
  gt 75 Otherwise False
• B True, if close to an obstacle (lt50cms),
  Otherwise False
• Configuration 3 (sound distance)
• A True, if noisy (value gt 50), Otherwise False
• B True, if close to an obstacle (lt50cms),
  Otherwise False