Transcript Presentation - CS Course Webpages

Self-Sustaining Solar Powered
Robot
Mason Drew
Mark Nolan
Wesley Varghese
Problem Background
• Most robots today can be put in three
•
categories: AC powered, battery powered, and
solar powered
Each has a significant weakness
AC – connected to outlet
Battery – batteries need replacing/recharging
Solar – need constant strong light source
• All need outside assistance to continue to
function as designed
Problem Statement
Robots are restricted by their energy source.
Some robots are required to be plugged into an
outlet at all times. Others use batteries, but
they must be replaced or recharged periodically.
And finally, some are solar powered, but they
must be in direct light at all times. All these
types of robots require too much outside
monitoring and assistance to operate for long
periods of time.
Problem Objective
The purpose of our project is to design a mobile selfsustaining robot. The robot should be able to operate
unassisted for long periods of time. To do this, the robot
should be able to perform a task while monitoring its
battery level. Once the robot senses that its battery has
dropped below a specified level, it will stop its current
task to seek a strong light source. The robot should be
able to navigate to the light and stop at it to charge the
battery. Once the battery is charged, the robot will leave
the light source and continue to perform the task
assigned to it.
Design Constraints
• Self-sustaining – The robot should be able to operate without any
•
•
•
•
•
assistance from the outside world.
Monitor energy – The robot should be able to monitor the battery’s
energy level at all times. It should know when it needs to seek
more energy and it should also know when the battery is done
charging.
Mobile – The robot should be able to navigate on a flat surface
without obstacles.
Light-seeking – The robot should be able to locate the strongest
light source in the area and navigate toward it.
Solar-Rechargeable – Once in a strong light source, the robot should
enter a charging mode where it consumes very little power and
stores the energy into rechargeable batteries.
Light weight – The robot will have to be light enough that the
motors can move it.
Existing Solutions
• Sorjourner
– NASA solar powered robot sent to Mars in 1997
– 78 days until rendered useless
• Hyperion
– Solar power exploration robot publicized by Mid 2001
– NASA supported research performed by
Carnegie Mellon University’s Robotics Institute
– Followed sun to maintain energy levels
– Tests ending in July proved successful
• Scoutwalker II/Sunseeker
– Scoutwalker II - robot designed specifically for mobility
– Sunseeker – stationary pivoting robot that detects light
Key Elements/Necessary Parts
• Robot: Boe-Bot
– Board of Education Circuit Board
• DB9 connector for serial interfacing (good useful during
programming and runtime communication)
• 2”x1 3/8” breadboard for circuitry expansion
• 16 input/output pins for interfacing with microprocessor
– Parallax Basic Stamp II-IC Microprocessor
• Program in written PBASIC (included in 2048 bytes of
EEPROM)
• On board voltage regulator (6-15 Volts -> 5 Volts)
• Comsumes only 8 mA of current running (100 μA sleeping)
• Holds 500-600 lines of code and executes up to 4000
instruction/sec
Board of Education
Solar Cells, Sensors, Battery, and
Charging
• Solar cells: Sundance Super Solar Cells
– 1”x1”x0.014” size per cell
– Provide efficient, cost-effective supply of 0.5V 125mA
– 4 pack (tentative count of 12 for a total 48 cells)
• Photo sensors
– 4 sensors distributed equally around robot
– Go through A/D converter to provide
• Battery: 6V 500 mAh NiMh flat ANTPack
– Lightweight (49 grams)
– Provides sufficient power for needs
– Measure using parallel resistor through A/D converter
• Charge controller
– Prevents overcharging
– Constant flow of energy with possible effiecenty increase by wave
transformations
Scheduling
Economic Analysis
Budget
Item
Boe-Bot Full Kit
6V 500mah NiMh Flat ANTPack
Sundance Solar Super Solar Cells .5 V 125mA 4-pack
Photo-sensors
A/D converter
Charge controller circuitry
Quantity
Price
1 $ 229.00
1 $ 13.50
12 $ 10.95
8 $
2.00
2 $ 10.00
1 $ 30.00
Estimated Shipping
Grand Total
Subtotal
$ 229.00
$ 13.50
$ 131.40
$ 16.00
$ 20.00
$ 30.00
$ 50.00
$ 439.90
Environmental and Safety Analysis
• Provides solution to real world applications that is
•
environmentally friendly
Safety procedures followed throughout design and on
through testing processes
Design Validation
• The testing environment will be a flat, smooth
•
•
•
•
surface without any obstacles
There will be two lamps in the room placed near
the floor with all other ambient light turned off
The robot will be placed in the middle of the
room and will start to consume energy.
When “hungry”, the robot will seek a light source
and replenish its power cells
Repeat
Conclusion
Create a self-sustaining solar powered
phototropic robot that is sufficiently
entertaining in its discharge cycle.