Transcript Fire Fighting Robot Design

Fire Fighting Robot Design
The V-Team
James Barnes – ME, ’04
Robert Kelbley – CpE, ’04
Christopher Pfeifer – CpE, ’04
Todd Stewart – CpE, ‘04
Advisors
Dr. John-David Yoder
Dr. Srinivasa Vemuru
Overview
Problem Statement
Components
Microcontroller
Sensors
Vehicle Design
Motors and Gearing
Results
Conclusions
Problem Statement
Objectives
Design a robotic device to seek a candle flame within
mock house and extinguish.
Robot will be taken to Trinity College to compete in
Firefighting Robot Contest
Benefits
Furthering robotics knowledge of group members and
society.
Small scale version could lead to improvements or a new
design for a large scale firefighting robot.
Allowing team to use engineering skills and teamwork to
solve multidisciplinary tasks
Mock House
Microcontroller
The microcontroller is the most important
part of the design – acts as brain for robot
Interfaces all sensors and motors
Contains all code for robot operation
MC68HC11
Advantages
HC11 and ModCon controller obtained – no expense
Familiar usage
Can be programmed in C
32 KB of RAM available in extended mode
Disadvantages
Non user friendly hardware interfacing
The Sensors
Sensors were needed to detect vicinity of
candle flame, exact location of candle
flame, and robot’s proximity to maze walls
Several sensors chosen
Hamamatsu UVTron Flame detector
Eltec Pyroelectric Sensor
Sharp GP2D02 IR Sensors
Optical Encoder
Hamamatsu UVTron
Chosen due to close connection to Fire Fighting
Robot Contest
Detects vicinity of candle flame, NOT exact location
Detects presence of flame by sensing emitted UV
light
Emits +5 V signal after UV source is sensed
Eltec Pyroelectric Sensor
Activated after UVTron sensors detect
flame in vicinity
Used to guide robot to exact flame location
Eltec emits constant +2.5 V analog signal
when flame centered
Signal voltage rises or falls depending on
objects movement through sensor’s field
of vision
Sharp GP2D02 Sensors
Infrared range detector
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Generate IR light pulses
Determine distance objects are from robot
Range of 10 to 80 cm
Use 2-wire serial interface
8-bit range value
Only takes reading when requested
Range Sensor Arrangement
Robot can detect obstacles in front
Ensure robot stays in center of hallway
Recognize doorways to enter rooms
Vehicle Design
The robot needed to:
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move with adequate speed
maneuver through the rooms
avoid hitting the walls
extinguish the candle
be upgraded easily
Design Specifications
Round base
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This helps prevent the robot from jamming in
corners
Turning the robot is accomplished with a
differential steering system
Power is provided by 9.6 V rechargeable
NiCd batteries
Fan is used to extinguish fire
Selected Motors and Gearing
Chosen motors: Permanent
magnet DC
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Available
Cost effective
Adequate power
Chosen gearing: Worm gear
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Available
Cost effective
Adequate gear reduction
Braking action
Motors and Gearing
Permanent magnet DC motors
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.05 Nm max torque with 1 amp max current draw
Maximum input voltage of 24v with maximum rotational
speed of 3400 rpm
Rotational speed of 1400 rpm with 9.6V battery
20:1 gear reduction with worm gear
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Obtained from a previous project with the motors
Rotational speed from motors reduced to 70 rpm
4 inch diameter wheels
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velocity of 14.7 in/sec with 9.6V battery
Fall Quarter
Winter Quarter
Completed Robot
Contest Results
Successfully completed qualifying trial to compete in main competition
Failed during first two runs of competition from damages incurred in travel
Successfully extinguished candle on last trial run in just under one minute
Conclusion
Successfully navigates maze and
extinguishes candle
Uses combination of Dead Reckoning and
Landmark Recognition for navigation
Uses sensors to pinpoint exact location of
candle and fan to blow out flame
The V-Team would to thank Dr. Vemuru, Dr. Yoder, Brad
Hummel and Dr. Hurtig for their help and guidance throughout
the project and the ECE Department and College of
Engineering for providing funding for the robot and trip to
Hartford.
Contest References:
1. http://www.trincoll.edu/events/robot/Rules/default.asp
2. http://www.trincoll.edu/events/robot/Results04/default.asp
Robotics References:
3. http://members.verizon.net/~vze2b2zf/robotpage.html
4. http://abrobotics.tripod.com/Snuffy/snuffy.htm
Part References:
5. http://bd.thrijswijk.nl/thrsim11/68hc11/about2.htm.
6. http://abrobotics.tripod.com/Snuffy/uvtron.htm
7. http://www.acroname.com
Book References:
8. Software and Hardware Engineering, Fredrick M. Cady,
Copyright 1997, Oxford University Press, Inc.