OB1 (Object Bot 1)
- an object grabber
(project recycled!)
Stats:
CPU: OOPic I
Sensors: Sharp GP2D12 IR range,
2 - homemade reflective
Drive: 2 - modified HiTec HS25BB
Gripper: 3 - HiTec HS25BB
Power: 8 - AA, 1 - 9v
Weight: not known.
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My first fully scratch-built robot was this one. This bot was
built around a contest designed by Front Range Robotics (
yahoo group, web site )
club member Ed Rupp. The object of the contest is find and remove certain
targets from a MiniSumo arena, while leaving other targets behind. Each of the
targets has a specific size, color, weight, and "taste" (resistance value) -
any of which can be sensed by the robot (click here for
contest rules). At the time, I was taking
an Artificial Intelligence class
(CS440) at Colorado State University, and decided this
challenge would be a great demonstration project!
The CPU for this robot is an OOPic
microcontroller, which I have found to be a flexible and easily programmed CPU
for robotics. Initially I tried using toy motors
for locomotion, but later switched to model airplane servos modified for
continuous rotation. The
servo gripper on the front uses unmodified model airplane servos. A
Sharp GP2D12 rangefinder is used for locating targets.
OB1 could (often) locate, pick up, and toss out a target -
but was too large to easily navigate the arena without knocking over other
targets. Since it was built for a demonstration project, time was too
short to work out the problem of sorting targets. But it was still a hit
with my classmates when I gave my presentation!
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Stomper
Insectronic walker
Stats:
CPU: MicroChip 16F84A
Sensors: SRF04 ultrasonic range
Motors: 3 - HiTec HS25BB
Power: 4 - AA Nmh, 1 - 9v Nmh
Weight: 23.7oz (673g)
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This walking robot is one that I built from a book by Karl
Williams "Insectronics
Build Your Own Walking Robot" .
The CPU for this bot is a Microchip
PICmicro 16F84A microcontroller. A very inexpensive (typically under $5
U.S.) microcontroller - however it requires a separate programming board
and (if you want to write your own programs) a compiler.PicBasic
Pro is the compiler mentioned in the book, though there are others such
as CCS PicC and
Proton. If you plan to build a lot of bots, the PICmicro
becomes more attractive as the programmer and compiler are a one-time
expense.
If you just want to build the robot and don't care to write your
own programs you can download the hex files from the
Karl's website and the program the 16F84A with an
inexpensive programmer. I built Myke Predko's "el-cheapo" programmer from his
book "Programming and
Customizing PICmicro Microcontrollers" . Be sure
to get a book that has both the PC board and software CDROM included!
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Stats:
CPU: Basic Stamp BS1-IC
Sensors: Sharp GP1U58Y IR,
2 - QRB1134 reflective
Drive: 2 - modified GWS S03N 2BB
Power: 4 - AA Nmh, 1 - 9v Nmh
Weight: 16oz (454g)
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Cyclops is my first combat robot. It uses a
Basic Stamp BS1-IC microcontroller for its CPU. The PC board is
home built but the chassis is Portland
Robotics Society's Mark
III chassis kit .
Sumo combat essentially is a shoving match between two bots - a
point is scored by shoving your opponent off the combat arena (the
"dojo"). Generally, a win is declared by scoring a point twice out
of three rounds. Cyclops competes in the autonomous MiniSumo class - up to
500 grams (16 ounce) weight, and 10 cm (4") square. The dojo is a black
circular platform approx 30" in diameter, with a white stripe around the edge
so the robot can sense the edge.
Click here for MiniSumo rules.
Cyclops held the championship at FRR for awhile in the fall
of 2003 but soon other robots started to exploit its weaknesses. I added model
train weights to bring it up to the maximum 500g weight and a tip sensor to
prevent being "scooped" by robots with drop down ramps. More recently
though, Cyclops has become target practice for MiniSumos with better vision.
Just for fun, here is a short MPEG video
of a recent combat in our club. The video is 2MB in size, so may take awhile to
download if you are using a phone/modem connection.
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OB2 (Object Bot 2)
Click for project details!
Stats:
CPU: OOPic II
Sensors: Sharp GP2D12 IR range,
2 - QRB1124 reflective,
homemade multispectral (color)
Drive: 2 - modified GWS S03N 2BB
Gripper: 1 - HiTec HS25BB
Power: 4 - AA Nmh, 1 - 9v Nmh
Weight: estimated 21oz (600g)
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This robot is my second attempt at an object-grabbing robot
(see OB1 above for my first attempt). OB2
is designed to find and remove targets from a MiniSumo arena, while
leaving certain other targets behind. Each of the targets has a specific size,
color, weight, and "taste" (resistance value) - any of which can be sensed by
the robot (click here for contest rules ).
OB2 uses an
OOPic II microcontroller, a
servo gripper , and a
Sharp GP2D12 rangefinder. The robot is built on a modified
Mark III MiniSumo chassis kit (a MUCH smaller footprint than my
original OB1!).
OB2 identifies targets by color, using a bright
surface-mount RGB LED as a light-source, and a visible-light phototransistor
for sensing the reflected light. In brief, the targets color is determined by
switching the RGB LED's colors individually and measuring the reflected light.
By analyzing the reflected values, OB2 can determine the targets color, and
then either remove it from the arena or keep it.
Since there is much more to this project than I can explain in
just a couple of paragraphs - more pictures, diagrams, and other
information are available on my OB2 project page.
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OOPic
Multi-I/O Board
Click for larger labeled image
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This is one of my more recent
OOPic design projects. The idea was to provide the
OOPic I, II, or II+ microcontroller with a single interface board
containing the most common interfaces used in many of my robots. This
board features up to 31 servo connections (with two separate power supply
connections), a dual 1-amp H-bridge (able to provide full pwm speed control for
two small dc motors), a regulated 1-amp 5-volt power source with six
connections, a power LED indicator, a speaker, and a true RS232 interface.
The Multi-I/O gives older OOPic's many of the capabilities of an OOPic R,
but with more available I/O connections! This board also provides serial
programming capability (SCP) with the OOPic II+.
Pictured is my prototype, built
onto an OOPic protoboard. A PC board version is also planned.
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A Future Project...
BYER
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"BYER" (BackYard Exploration Rover) is
inspired by NASA/JPL/Cornels
Mars exploration rovers
"Spirit" & "Opportunity." I have wanted to build an semi-autonomous
explorer robot for some time; but only recently acquired a small RF video
camera that could be used to provide a robots-eye view of the world.
A 2-way data link, environmental sensing (temperature/direction), and force
feedback could also be implemented. One could even simulate
the light-travel time delay that is experienced for the Moon or Mars (or
anywhere else for that matter)!
Yeah, I don't have NASA size budget, but this
still could be one cool demonstration project!
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