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Autonomous Paintball Sentry Gun

by sentryGun53 on February 1, 2011

Table of Contents

Autonomous Paintball Sentry Gun . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Intro: Autonomous Paintball Sentry Gun . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Step 1: Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Step 2: Arduino . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Step 3: Servo Motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Step 4: Constructing the Base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Step 5: Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Step 6: Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Step 7: Using the Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Related Instructables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
Intro: Autonomous Paintball Sentry Gun
Make your own, custom AUTONOMOUS SENTRY GUN!

A Microcontroller Contest Finalist and Runner Up Winner.

This sentry gun autonomously tracks, aims, and shoots at targets, using:
-An airsoft or paintball gun
-A webcam to find targets
-A computer to process the video feed and aim the gun
-Servo motors to physically aim the gun and squeeze the trigger
-A sturdy tripod base
-A microcontroller to interface between the computer and the servo motors
-Lots of camo paint
The end result is a paintball/airsoft spewing robot, that can turn the tides of any match.

Video if it in action here .

Want to build your own?

You're in luck! All the help and information you will need is here, and the software is free and open-source. Lots of people have already used this system in their own
sentry guns, with successful results.
So go ahead, make your own, and soon your own backyard will be no-man's land, too!

P.S. take pictures during the project, and when you are finished, send me a picture, and a description of your project, and I will feature it on the Successful Projects page
of my website. Thanks!

Image Notes
1. Airsoft M4 machine gun
2. Webcam
3. Arduino and custom PCB (inside waterproof compartment)
4. Servo motors to pan and tilt the gun
5. USB cords go to computer
6. Sturdy tripod base
7. Control switches: -Reload -Servo Power -Safety (gun power)

Step 1: Parts List

Airsoft / paintball gun, or other 'projectile dispenser'
$30 Webcam
$25 Arduino (or equivalent)
$27 3 Servo motors (pan, tilt, trigger) $9 ea.
$10 Assorted screws, nuts and bolts
$9 Wood/metal for construction
$5 USB A to B cable
$2 Some 22 gauge solid wire
$2 Servo battery box
$110 TOTAL

Also, you will need a laptop or computer to run the sentry gun program. $250 for a cheap netbook, if you don't have anything else...

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
Step 2: Arduino
What's an Arduino? ...and how do you pronounce that, anyway?

An Arduino is a microcontroller. It plugs into a computer with a USB cord. On the Arduino board, shown below, there is an ATMega328 microchip, as well as 14 digital
input/outputs, 6 analog inputs, and a USB port.
That's not all, but it's everything that you will need to know about, to build a sentry gun. For complete details on the Arduino board, go to
http://arduino.cc/en/Main/ArduinoBoardUno.

You will use the Arduino board to take commands from the computer, and drive the servo motors as the commands dictate. Also, it will provide you with hookups for
expanding your own ciruit easily afterwards.

Where to buy your own Arduino board

Image Notes
1. An Arduino Uno, the latest Arduino board. There are many different styles and models of Arduino board, and almost any of them will work in this project, as long
as they have digital input/outputs, and UBS/serial communication

Step 3: Servo Motors

To control the movement of the gun, you will use 2 servo motors.

The "pan" servo controls the side-to-side movement of the gun.

The "tilt" servo controls the up-down movement of the gun.

Your remaining servo motor will be used to squeeze the trigger of your gun.

For heavy guns, such as the paintball gun shown below, you might want to get some stronger servo's.

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 Image Notes
1. A standard servo. These will work fine for light-weight guns, but larger guns
such as paintball guns will require heavy-duty servo motors.

Image Notes
1. Tilt servo - controls the up-down (y-axis) movement of the gun
2. Pan servo - controls the side to side (x-axis) movement of the gun
3. Trigger servo - pulls the trigger of the gun
4. Semi-automatic paintball gun

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 Image Notes
1. Tilt servo - controls the up-down (y-axis) movement of the gun
2. Pan servo - controls the side to side (x-axis) movement of the gun
3. Trigger servo - pulls the trigger of the gun
4. Semi-automatic paintball gun

Step 4: Constructing the Base

Now is time to put everything together. How you do this is largely up to you.

Some design considerations:

The gun should be balanced on the tilt servo. Find the gun's center of gravity, and mount it at that point. This is so the servo dosn't have to waste energy trying to
keep the gun level. IMPORTANT: when the servo has no power supplied to it, the gun should tilt freely, and when you move it with your hand it should not return to level -
rather it should stay right where you let go. Spend a lot of time getting this balance just right, it is a major factor in the effectiveness of your finished sentry.

Stability is key. You want a strong, solid sentry. Vibration will cause a lot of issues with the camera later, if you don't suppress it now. I'm not going to teach you how to
build well, but keep in mind that screws and bolts are better than nails, nails are better than zip ties, zip ties are better than staples, and even staples are better than duct
tape.

The webcam must be solidly mounted to the base. You want it close to the gun, but the gun barrel can't ever move into the camera's view - it will see that as a target.
Also, the webcam should be as solid as possible - vibration from the servo's and gun firing will mess it up.

Depending on the expected use for the sentry (airsoft? paintball? water jet? laser?), you may need to add a durable compartment to hold the electronics.

Finally: tripods are cool, but they can be prone to a lot of shaking if built badly, or if you use a flimsy camera tripod. Surveyor's tripods are great for sentry guns - they are
heavy, stable, and often adjustable too.

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 Image Notes
1. webcam is screwed onto base - very stable
2. switches and LED's
3. Gun is balanced on tilt servo
4. Compartment for electronics - made from durable lock-n-lock box
5. Stable base - made from 2 sheets of 3/4 inch plywood, and 2 sheets of 1/4 inch aluminum. The tripod legs slide into holes drilled for the purpose, and are fixed in
by bolts.
6. Copper pipe for legs

Step 5: Wiring
Arduino :
The Arduino connects to the computer through the USB A to B cord. This also powers the Arduino. Various other things wire to the Arduino:

Servos :
You will need a seperate power source for your servo's. I reccomend 4 C-cell or D-cell batteries, wired in series to make 6V. Check the data sheet to find the power
consumption for your servo's!
Servo motors have three wires: power, ground, and signal. Each servo's power wire is typically red, and should be connected to the (+) wire from your servo power
source. The ground wire is typically black or brown and should be connected to a ground pin on the Arduino board, and to the (-) wire of your power source. The signal
wire is typically yellow, orange or white and should be connected as follows: The x-axis servo's signal wire goes to the Arduino's digital I/O pin 3, the y-axis servo to pin 4,
and the trigger servo to pin 6.

You can also add some optional switches and LED's , but they are not necessary:
-USB status indicator LED to digital I/O pin 6
-firing indicator LED to digital I/O pin 2
-a "power switch" between the (+) from the servo power source and the servo's, to turn off the servo's and save battery power
-a "safety switch" between the (+) from the servo power source, and the trigger servo, (but after the 'power switch'), to turn off the firing functionality easily and quickly (in
an emergency)
-a 'reload' switch, wired between +5V from the Arduino and digital I/O pin 7, to set the gun in a programmable position convenient for reloading

Solder everything if you can. If you want, make your own arduino 'shield' with all the conections. This allows you to "plug in" the Arduino, and "unplug" it when it is needed
elsewhere, without losing track of which wires go to which pins.

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 Image Notes Image Notes
1. Wire your "power switch" in here 1. Custom shield - solder pin headers to some perf-board, in the right places for
2. Wire your "safety switch" in here the Arduino pins. You don't need headers for the Analog In set of sockets on te
3. You may also want to add a resistor in series with each LED too, for Arduino, or for the digital I/O pins 8-13 and AREF. Don't use the solder on this
protection. The value depends on your LED, but 5K should work fine for most. perf-board as a reference - I was messing around with an h-bridge IC to control
4. These are the pin labels seen on the Arduino board - if they are difficult to the airsoft gun....
understand, refer to the written directions above. 2. Servo power source - comes from the 4 D-cell batteries. I soldered this nice
5. These are NOT the correct pin numbers! (see box to left) power cord to the battery wires, and a matching jack to the 'shield' (on
6. remember to connect the ground of the servo power source to the Arduino underside).
ground 3. Arduino board - what else.

Step 6: Software
Now you have your sentry gun built, the wiring finished, and no doubt you want it to do something!

Before you plug your Arduino into your computer, go download the Arduino IDE .

If you have a Diecimila or older board, set the Power Jumber to USB.
Now, plug your Arduino in - the green Power LED on the Arduino should light up, and the orange LED might flash a few times. Good job!

The Arduino IDE is what you will use to load the Arduino program onto your board. However, you will need the seperate, Processing IDE to run the computer side of the
code. This does the camera tracking, and sends commands to the Arduino.
Go download the Processing IDE .

Open both Processing IDE and Arduino IDE. They should look very similar.

With a little bit of trial-and-error on the code, you should have a working sentry in no time! So get started typing!

Just kidding, of course.

The next thing you need to do is download the JMyron, blobDetection, and controlP5 libraries from processing.org. Find the link to each library on that page. The
instructions for downloading each one can be found by clicking on it's link.

You are ready to go get the code! Download the latest version it from my website . After you have saved it to your computer, unzip the folder, and follow the directions in
the strategically placed README.txt files.

Open the Arduino code in the Arduino IDE. Make sure you have selected the proper board and serial port from the Tools menu. Next, click 'Verify', wait for it to say "done
compiling", then click 'Upload'. The RX and TX LED's on the Arduino board should pulse a little, then stop.

Congrats! You have finished programming the Arduino!

Plug in your webcam. Install the drivers, if you haven't already.

Now, open the Processing code in the Processing IDE. Click 'Run', and watch the magic happen!

Of course, for many of you this will not work on the first try. Don't get upset, it's normal. Pop me an email with any problems, or leave a comment below.

A tip for Windows 7 users, from ljfa321:

If you are getting this error when you try to run: processing.app.debug.RunnerException: UnsatisfiedLinkError: D:\Software\processing-
1.2.1\libraries\JMyron\library\JMyron.dll: Can't find dependent libraries:
http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
"Reason : Windows 7 doesn't come with MicroSoft C libraries, which were normally include in the other (older) Windoes system.
This means there are two files missing in the Windows 7 system: MSVCP71.DLL and Msvcr71.dll
Solution : Download these two files from here:
http://www.addictivetips.com/?attachment_id=38105
AND!
For Windows 7 32-bit OS: put both dll files inside Windows/System32 folder
For Windows 7 64-bit OS: put both dll files inside Windows/SysWOW64 folder."

Image Notes
1. This is what you want...

Step 7: Using the Software

When you run the code, two windows should pop up. One is the Webcam View and the other is the Control Panel.

In Manual Mode, you can aim and fire by pointing and clicking on the webcam view. In Autonomous Mode, the software takes over, and your gun gains a life of it's own!
Give it a little time to adjust to the background, and then it will shoot at anything that enters its view.

Play around with the other functions as well - Auto/Semi-auto, hide camera view, etc.

Calibrating - your servo and camera arrangement is probably unique, so you will need to calibrate it the first time.
You can do this by adjusting the values of xMin, xMax, yMin, and yMax, at the beginning of the code. Play around with them untill you have the gun aiming where you
point the mouse on the webcam view. A useful tool to do this is to watch the numbers scrolling by at the bottom of the Processing IDE while you run the code.

You may also need to calibrate the servo positions set in the Arduino code:

To set the reloading position, change these lines :

if(digitalRead(7) == HIGH) {
xPosition = 110 ;
yPosition = 135 ;
fire = 0;
}

To set the home position (no USB communication), change these lines :
if(idle) {
idleCounter++;
if(idleCounter > 10000) {
analogWrite(5, 50);
delay(250);
digitalWrite(5, LOW);
idleCounter = 0;
}
else{
digitalWrite(5, LOW);
}
xPosition = 110 ;
yPosition = 100 ;
fire = 0;
}

To set the 'squeezed' and 'not squeezed' positions for the trigger servo, change these lines :
void Fire(int selector) {
if(selector == 1) {
fireTimer++;
if(fireTimer >=0 && fireTimer <= triggerTravelMillis) {
trigger.write( 90 );
digitalWrite(2, HIGH);

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 }
if(fireTimer > triggerTravelMillis && fireTimer < 1.5*triggerTravelMillis) {
trigger.write( 140 );
digitalWrite(2, LOW);
}
if(fireTimer >= 1.5*triggerTravelMillis) {
fireTimer = 0;
}
}
if(selector == 3) {
trigger.write( 90 );
digitalWrite(2, HIGH);
}
}
void ceaseFire(int selector) {
if(selector == 1) {
fireTimer = 0;
trigger.write( 140 );
digitalWrite(2, LOW);
}
if(selector == 3) {
trigger.write( 140 );
digitalWrite(2, LOW);
}
}

Image Notes
1. Open Camera Settings
2. Set current frame as background (in autonomous mode)
3. Toggle between autonomous and manual modes
4. Fire your gun with automatic fire (holds trigger) or with semi-automoatic fire (squeezes trigger repeatedly)
5. Show the view from the camera
6. The live feed from the webcam
7. aiming crosshairs - used in manual mode

Related Instructables

Das Uber Project Mackra Robotic Talking laser tripwire

Airsoft Gun as of 1/24/2011 Turret by Nerf sentry
Arduino Airsoft How to build a Turret by (Photos) by kyle bomb by
RazorConcepts
Turret by Level 3 Sentry Miltron_B brinkerhoff doby162
12grahamb Gun by zzzdude

Comments
50 comments Add Comment view all 55 comments

starkec says: Feb 7, 2011. 11:46 AM REPLY

when trying to run i keep getting this error,

processing.app.debug.RunnerException: UnsatisfiedLinkError: D:\Software\processing-1.2.1\libraries\JMyron\library\JMyron.dll: Can't find dependent

libraries
at processing.app.Sketch.placeException(Sketch.java:1543)
at processing.app.debug.Runner.findException(Runner.java:582)
at processing.app.debug.Runner.reportException(Runner.java:558)
at processing.app.debug.Runner.exception(Runner.java:498)
at processing.app.debug.EventThread.exceptionEvent(EventThread.java:367)
at processing.app.debug.EventThread.handleEvent(EventThread.java:255)
at processing.app.debug.EventThread.run(EventThread.java:89)
Exception in thread "Animation Thread" java.lang.UnsatisfiedLinkError: D:\Software\processing-1.2.1\libraries\JMyron\library\JMyron.dll: Can't find
dependent libraries
http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 at java.lang.ClassLoader$NativeLibrary.load(Native Method)
at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1803)
at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1728)
at java.lang.Runtime.loadLibrary0(Runtime.java:823)
at java.lang.System.loadLibrary(System.java:1028)
at JMyron.JMyron.(JMyron.java:14)
at Turret_05_03.setup(Turret_05_03.java:142)
at processing.core.PApplet.handleDraw(Unknown Source)
at processing.core.PApplet.run(Unknown Source)
at java.lang.Thread.run(Thread.java:619)

I have installed jmyron as instructed in the file but i still get this error :(
Your help would be greatly appreciated :)

sentryGun53 says: Feb 7, 2011. 1:17 PM REPLY

Hey there, The .txt file in theJMyron download has an inaccuracy:

Copy the "JMyron" folder found in this directory into the Processing/libraries directory.
NO! Put that folder instead at C:\Users\ USERNAME \Documents\processing-1.1\processing-1.1\libraries

Copy the "JMyron Examples" folder into your Processing Examples folder.

IMPORTANT FOR WINDOWS USERS: there is a folder called "Extra DLLs" - those are DLLs that JMyron depends on so make sure they're copied into
your system's DLL search path - such as the Processing root directory, or even C:\windows\System32.

If Processing is already running, then restart it.

torivc says: Mar 13, 2011. 8:46 PM REPLY

Can't wait to do your build.
However, I did the same thing and no results
can you explain a little more on your instructions:

"IMPORTANT FOR WINDOWS USERS: there is a folder called "Extra DLLs" - those are DLLs that JMyron depends on so make sure they're copied
into your system's DLL search path - such as the Processing root directory, or even C:\windows\System32."

Place "Extra DLLs" to system's DLL search path" I don't understand this.

a video tutorial would be great for your instrucable

sentryGun53 says: Mar 14, 2011. 12:30 PM REPLY

Put them inside system32, that should be inside the search path. Actually, a lot of the time it will work fine without doing this anyways.
Cheers. Any more questions, let me know!

ljfa321 says: Feb 9, 2011. 7:50 PM REPLY

I just run into that problem yesterday, seems like they doulbe do the packaging work

sentryGun53 says: Feb 10, 2011. 9:40 AM REPLY

Well, the library was originally made for older versions of Processing. Newer versions store the libraries in a different palce. The instructions and
file packaging were not updated on the JMyron site, and many other libraries as well.

ljfa321 says: Feb 10, 2011. 8:49 PM REPLY

ok, that make sence XD

BTW, do you know what kind of souce I will be able to find a air solenoid?

I want to use it to control the release of compressed air.

Ask every shops I can think of in my town and still no luck.

sentryGun53 says: Feb 11, 2011. 6:38 PM REPLY

FESTO, AndyMark, SMC, Automation Direct

ljfa321 says: Feb 12, 2011. 3:35 PM REPLY

thx alot

ljfa321 says: Feb 13, 2011. 11:29 PM REPLY

Something funny happen, I have no problem with this setting in my Windows VISTA machine, but fail to work when I try to install it
to my Windows 7 machine.

The error message is exactly the same

(processing.app.debug.RunnerException: UnsatisfiedLinkError: D:\Software\processing-1.2.1\libraries\JMyron\library\JMyron.dll:
Can't find dependent libraries)

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 I event try to copy the entire working folder from VISTA to 7, but still no luck, and I do put the DLLs in to both process root and
C:\Windows\System32.

Any idea how this happened?

BTW, my windows 7 machine is completly clean, I only install the new version of JAVA since the one come with the installing CD
is old I think.

ljfa321 says: Feb 13, 2011. 11:44 PM REPLY

Also, my Windows7 machine don't have a webcam installed, perhaps thats the reason of the error message?

sentryGun53 says: Feb 14, 2011. 1:11 PM REPLY

well, it could very posssibly be the lack of a webcam. Try running the code on the vista machine, without the webcam
plugged in, and see if you get the same error.

ljfa321 says: Feb 15, 2011. 10:03 PM REPLY

I actually bought a webcam to connect to the windows7 machine this morning. The webcam work like a charm, but the
process still show the same error massage.

Also, I try to put the two dll files all over the place, but still got no luck so far.

I will keep trying tonight~

ljfa321 says: Feb 15, 2011. 10:49 PM REPLY

OK, problem solved, you might want to add this to your tutorial, since all windows 7 machine should inconter this
problem.

Reason: Windows 7 doesn't come with MicroSoft C libraries, which were normally include in the other (older)
Windoes system.
This means there are two files missing in the Windows 7 system: MSVCP71.DLL and Msvcr71.dll

Solution: Download these two files from here:

http://www.addictivetips.com/?attachment_id=38105

AND!

For Windows 7 32-bit OS: put both dll files inside Windows/System32 folder

For Windows 7 64-bit OS: put both dll files inside Windows/SysWOW64 folder

Than the program should run with no problem.

==========================================

New problem occurs now, but not a very big deal to me though.

Still, in Windows 7 machine, the behavior of the portal sound track is weired.

When start the program, the first sound track (deploying~) plays no problem, but whatever the sound track comes
after that, tent to lag forever at the end of it.

Example: press RUN > First sound: "Deplaying" > Second sound: "Will you come over
herererererererererererererererererererer................"

The tracking still works fine and smooth while the sound is lagging, it just really creeped me out when I first heard
this at 1:30am by myself XD"

sentryGun53 says: Feb 16, 2011. 11:49 AM REPLY

Ok, thanks for the tip, I'll put that on the software step. Nice work researching the problem!

ljfa321 says: Mar 11, 2011. 1:22 AM REPLY

Just ran across a few interesting idea for the sentry to find distance of the target.

1. http://luckylarry.co.uk/arduino-projects/arduino-sonic-range-finder-with-srf05/

Its basically using a ultrasonic range finder on arduino.

Problem: limited distance(about 10m max), and almost imposible to focus on small object.

2.http://hackedgadgets.com/2010/11/24/laser-range-finder-build/
homemade laser range finder, should be a very good one for sentry

Problem: it's not easy, almost like another full profect, and the camera unit are damn expansive......

3: http://sites.google.com/site/todddanko/home/webcam_laser_ranger
another laser range finder, but instead using chip and camera unit like the above one, this one use webcam and computer Software to do the job.

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 Problem: now we really need to mount an second webcam on the gun berrel.

=====================================================
************************************************************************************
4: http://hackedgadgets.com/2008/09/03/webcam-rangefinder-2/

Webcam range finder.

Probebly the must practical way on this project, it only need to use the webcam we use for the sentry tracting. Its just a simple way to calculate the distance
by pre set the object's hight (in our case, average human hight, aka the tracked "block's" hight), and pre set another number called "vertical AOV" ( vertical
angle of view : since the link to the original post is dead, I'm still trying to figure out if this mean the hight of the farest place in webcam's view or the hight of a
certain distance in camera's view [more likely] )
Even though the original post is dead already, the concept looks simple enough to directelly write into the sentry program without any hardware modification.

-Jason

sentryGun53 says: Mar 11, 2011. 7:07 PM REPLY

Don is experimenting with the openCV library (outside of Processing), using it with stereo vision to find range, with promising results.
Anybody have success with the openCV library for Processing?

ljfa321 says: Mar 5, 2011. 4:05 PM REPLY

Hi, I have 2 question for the Code Version 5.11,

1: How to run software without an Arduino plugged in?

2: Can I choose the input device of the video?

Thanks.

Jason

BTW: its ljfa321 not lgfa321 :P

sentryGun53 says: Mar 5, 2011. 5:33 PM REPLY

Find the first value in the Processing code, called runWithoutArduino. by default this is set to false. Set it to true to run without the arduino.
Incidentally, the next version of the code will automatically detect if there is an arduino attached, and if not then it will automatically set runWithoutArduino
to true.

I don't know of a way to choose the video input. That is not a part of the code, it is handled inside the JMyron library. A quick search on processing
forums yields one person with the same question , but nobody answered them.
Perhaps you can choose 'default' video source on your computer's Control Panel? Let me know if you find anything. Sorry i cant help any more than that!

Cheers
-Bob

ljfa321 says: Mar 11, 2011. 12:58 AM REPLY

Thanks, you already helped me a lot!

I'm still working on ways to change the video input, but GraphEdit might be a solution. I just start learning how to use it.

Thanks

-Jason

Vyger says: Feb 26, 2011. 11:46 PM REPLY

So how good would this work for keeping deer out of gardens? They are out mostly at night so it would have to be infrared.

sentryGun53 says: Feb 27, 2011. 4:38 PM REPLY

Seems to me that just some flashing lights and loud noises would keep them away, but you could use a water jet too I suppose

ljfa321 says: Feb 27, 2011. 12:59 PM REPLY

should be pretty good at doing that.

You can use both water jet or BB's.

sommmen says: Feb 27, 2011. 9:49 AM REPLY

put a litle laser on the gun!

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 ljfa321 says: Feb 18, 2011. 4:16 PM REPLY
I was doing some research on the ways to connect 2 or more webcam video steam into one while waiting for my new servol to come. (I burned one of my
heavy duty servol by supply 7.5V to the 6V servol :P )

Don't have any luck yet for a reliable way to connect 2 webcam, but I cam across something interesting.

http://www.aroundvision.com/purchase.htm

Basically, its a cheap device using mirror to make a webcam views 360-degree, and he have a software to adjust the video stream so it won't looks too odd.

It looks like a fun thing to try, but it will be extreamly hard to adjust the video into a non-curly one, though It will be hard for the sentry software to aim properly
since a straight line in real world won't be that staight in the video stream.

Sorry for my English but I tried my best to describe it :P

ljfa321 says: Feb 18, 2011. 4:24 PM REPLY

Also, the first problem might inconter while try to combine views from 2 webcams will be the brand of the webcam.

Its seems like most computer will have no problam getting video from 2 webcam at the same time; its the software came with the webcam that will cause
problem.

Simply put, two webcams using the same software to run will have problem running at the same time due to the problem occur while running 2 same
software at the same time.

It will be much easier to use 2 webcams from different brand which have two different softwares.

But than the different views (as for contract, size, zoom, colour, etc) of the webcam may cause problem when merge two videws into one...........

sentryGun53 says: Feb 25, 2011. 6:53 AM REPLY

Hey, I found a possible solution for this. It is called a video input quad multiplexer.

Basically, this is a device that takes input from four cameras, and combines them into one output. The output signal is a standard video signal, so the
computer reads it as one camera.

However, this output signal is divided into quarters, each quarter showing one of the original camera views. The code could easily be worked to split
these 4 views apart, and re-join them in a horizontal configuration, giving you a wide-range view, from 4 seperate cameras.

If anybody has a multiplexer like this, or knows where to get one, let us know!

ljfa321 says: Feb 25, 2011. 3:06 PM REPLY

Thank you, you always put me into the right direction!

I use the word Multiplexer as a direction and guess what I found?

Stereoscopic Multiplexer
http://www.3dtv.at/Downloads/Index_en.aspx

A software that works like a hardware multiplexer. Even better, I take two USB webcam as imput and put the video stream side by side!!!

I'm still waiting my second webcam to come, and haven't succesfully run the software with 1 webcam, but this looks promissing.

sentryGun53 says: Feb 19, 2011. 4:33 PM REPLY

Some of us have toyed with the idea of using 2 cameras, but not for a wrap-around view; instead, one would be on the gun, and another would be
stationary on the base. The stationary camera would detect targets with motion-sensing, then would work with the barrel camera to precisely aim at
the target.
However, we haven't found any way to read two seperate webcams with JMyron. Perhaps there is an option for this using another Processing library,
perhaps Processing.video or OpenCV? I'll continue to look into it, but if anybody else knows anything about this than leave a comment or email me.
Thanks

ljfa321 says: Feb 23, 2011. 10:45 AM REPLY

Do you remember the initial version of the program only track orange target?

Is it actually colour tracking?

If so, will it be possible to set a different trigger (in my thought, battle switch), which will be activate when a orange target that is smaller than a size be seen?

And the battle switch ( the second trigger) can disconect the trigger servo when seen a orange target.

Maybe this might work as safe target identification?

sentryGun53 says: Feb 23, 2011. 11:15 AM REPLY

Cool idea. It is quite easy to track colors, in fact it is much easier than the current motion-tracking.
I had already prepared new code that allows for color tracking in addition to motion tracking. So, it would be easy to change this around a little to do what
you are thinking of.

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 ljfa321 says: Feb 23, 2011. 9:32 PM REPLY
Thats sweet!!! you already finished the hardest part!

The rest is just telling it what to do when see the specific colour.

I think I will put that into my design.

(ex: when see movement, only fire BB's; when see red, fire rocket as well !! )

BTW: the ability to decide the tracked target size on the new version of the software is awsom! Now my sentry won't track its own BB's :P

(That happened probebly because I slowed my airsoft gun's voltage to the slowest when I was testing at home)

sentryGun53 says: Feb 21, 2011. 2:50 PM REPLY

How you construct the physical mounting is really up to you, but if you want I can send you some close-up pics of my setup. Everybody's is unique!

davidly1982 says: Feb 21, 2011. 6:37 PM REPLY

Can you please? That would be great.

sentryGun53 says: Feb 23, 2011. 8:04 AM REPLY

email?

Vick Jr says: Feb 21, 2011. 1:08 PM REPLY

I have a problem with the sounds.

They seem to repeat and they are laggy. I can hear parts of one sound playing while others play at the same time. Some play fine but others get stuck. Any
ideas? Is there a way to stop previous sounds playing before telling a new one to play?

sentryGun53 says: Feb 21, 2011. 3:21 PM REPLY

Hmmm, this problem seems to be pretty common. Iml looking into it, and I'll try to fix it for the next code version.
Can you tell me what operating system and software version you are using, thanks.

Vick Jr says: Feb 22, 2011. 5:21 AM REPLY

Windows XP
processing 1.2.1
turret_05_03

Thanks you. If you can fix this it would be great! I'l also look into it when I have time.

Vick Jr says: Feb 22, 2011. 8:33 AM REPLY

I made a quick fix. I'll post it later. Basically I changed your code to use an audioSnippet array, then before playing a sound, I pause whatever
sound was last played, in case it's still playing. I also pause whatever sound I'm about to play.

Vick Jr says: Feb 22, 2011. 4:29 PM REPLY

Never mind. It doesn't work. I've noticed that it only seems to lag if you move the turret (or it moves itself in auto mode) while a sounds is
playing. Maybe the sound playing isn't running on a separate thread so when the main program slows down, the sounds do too. We should
try another audio library. That Or I'll use my waveshield.

In either case. I successfully tested my turret today and aside from frequent jamming and glitchy sounds, it worked well and was very
impressive. Thank you for this instructable!

I will continue to improve the design and code and will submit my turret to your "featured successful projects" page.

sentryGun53 says: Feb 23, 2011. 7:56 AM REPLY

The sounds were interfering with the tracking? I bet the program is waiting for the sound to finish playing... i think i might have used a
delay() for that. I'll check it out.

ljfa321 says: Feb 23, 2011. 1:38 AM REPLY

Hm, since like your problem are different with my Windows7 one.
Mine just keep repeat the last word of the second sound track.
However, the tracking works perfectly even the sound if screwed up.

lug big lug says: Feb 22, 2011. 4:05 AM REPLY

You should have some of those sounds in a really deep voice like when it says sentry mode activated..... that would be cool.....

http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/
 ljfa321 says: Feb 21, 2011. 12:01 PM REPLY
Ok, everything is working for the new servo <3

15kg torque is awsom!!!!

Now I just have to wait until the university reading break is over and the shop open to build the body of the sentry. I will build a very simple base first to test
how the servo react to heavy load, and will go straight to the full scale of this

http://img4.imageshack.us/img4/7015/sentrygun1.jpg

While waiting, I will test different type of materials, since the end result will be really heavy If I go all metal or even all wood...........

sentryGun53 says: Feb 21, 2011. 2:48 PM REPLY

Team Fortress 2... nice. Glad to hear the hevy-duty servo's work out, i'll try some of those on my next version. Good luck with making that!

ljfa321 says: Feb 21, 2011. 11:19 PM REPLY

Thanks, the only problem of those heavy-duty servo is their ability to drain the batteries........
4AA for 3 Min..............
I will either need to find a badass rechargable battery pack, or get a wall plug.

davidly1982 says: Feb 21, 2011. 2:48 PM REPLY

I am a newb at this and this is my first eletronical project. How did you attach the servos to the paintball gun? Did you drill into it?

zachtos says: Feb 18, 2011. 11:57 AM REPLY

Hmm, I may have to try this for my IRcombat laser tag sytem.

Dannne11 says: Feb 13, 2011. 12:16 PM REPLY

im getting the error

processing.app.debug.RunnerException: unexpected char: 'i'

at processing.app.Sketch.preprocess(Sketch.java:1352)
at processing.app.Sketch.preprocess(Sketch.java:1205)
at processing.app.Sketch.build(Sketch.java:1568)
at processing.app.Sketch.build(Sketch.java:1553)
at processing.app.Editor$DefaultRunHandler.run(Editor.java:1485)
at java.lang.Thread.run(Thread.java:619)

sentryGun53 says: Feb 13, 2011. 1:45 PM REPLY

Make sure you are opening the Processing Code in Processing, and the Arduino Code in Arduino.
Also, if you copy-pasted the code in, make sure you get the entire code.
Good luck

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http://www.instructables.com/id/Autonomous-Paintball-Sentry-Gun/