Wednesday, January 28, 2009

Solution - Parallax motor control

Below is a bit of code I found that solves my previous question about controlling the Parallax servo motors. From the Parallax website, I found that these motors require a pulse of 1.5 ms every 20 ms in order to stand still . Pulses shorter than this cause clockwise rotation. Pulses longer than this cause counter clockwise rotation.

With this code running, you can use a screwdriver to adjust the internal potentiometer to let the motor stand still. Change the "1500" delay to another number to observe the directional control.
If anyone knows how to accomplish this using the Arduino libraries I would appreciate knowing.

Paul.

int servoPin = 10;
void setup()
{
pinMode(servoPin,OUTPUT);
}
void loop()
{
digitalWrite(servoPin,HIGH);
delayMicroseconds(1500); // 1.5ms
digitalWrite(servoPin,LOW);
delayMicroseconds(18500); // 18.5ms
}

UPDATED BY IVAN:

Try this code.

int servoPin = 9;
void setup()
{
pinMode(servoPin,OUTPUT);
}
void loop()
{
int temp;
for (temp = 0; temp <= 100; temp++)
{
digitalWrite(servoPin,HIGH);
delayMicroseconds(1500); // 1.5ms
digitalWrite(servoPin,LOW);
delay(20);  // 20 ms
}

for (temp = 0; temp <= 30; temp++)
{
digitalWrite(servoPin,HIGH);
delayMicroseconds(1600); // 1.6ms
digitalWrite(servoPin,LOW);
delay(20); // 20ms
}

//delay(100);

for (temp = 0; temp <= 31; temp++)
{
digitalWrite(servoPin,HIGH);
delayMicroseconds(1400); // 1.4ms
digitalWrite(servoPin,LOW);
delay(20); // 20ms
}
}
Hi All,

Has anyone had success controlling the new Parallax servo motors?

Unlike examples we've seen in the lab, these rotate continuously
and do not appear to be controllable in the way suggested by code
examples on the Arduino sites or by Ivan's example.

Any tips would be appreciated.

Paul.

Monday, January 26, 2009

Component bags in the lab


Hi all, 

The bags for Henrique-Paul and Krishna-Joe are in the lab.
Dr. Green and Dr. Walker, I have also put there the tool box with the rest of the components and motors.


Wednesday, January 21, 2009

Purchase of Components - PLEASE READ AND UPDATE ASAP


Ok guys, here is the list of components I think we should buy.
I have granted everyone with Admin permissions so if you need something specific for your project just update the post adding whatever you need at the end. Also, feel free to add comments or suggestions about components you think we might need for future projects.

PLEASE, ADD ANYTHING YOU THINK YOU MIGHT NEED BY TONIGHT, TOMORROW I WILL GIVE THE INFORMATION TO HENRIQUE TO MAKE THE PURCHASE.

If you click on the name of each item it would take you to a website with more info.
Here it goes.




ELECTRONIC COMPONENTS (www.mouser.com):

- IR Distance Sensors (GP2Y0D810Z0F) - 8 x $2.60 = $20.80
- Red 5mm LEDs (WP7113ID) - 20 x $0.09 = $1.80
- Orange 5mm LEDs (WP7113ND) - 20 x $0.09 = $1.80
- Yellow 5mm LEDs (WP7113YD) - 20 x $0.09 = $1.80
- Green 5mm LEDs (WP7113GD) - 20 x $0.09 = $1.80
- Miniature Switches (B3F-1022) - 16 x $0.23 = $3.68

Here is the list from mouser. So far, $39.00 + shipping.

Mouser doesn't carry any cheap photoresistors so I found them in RadioShack. We will buy them in the physical store to save the shipping costs.
Here is some information. The pack of 5 costs $2.99. We could order 2 or 3 of them. 


======================================================
NOW LET'S ADD THE SPECIFIC COMPONENTS FOR EACH PROJECT
======================================================

Apoorva & Adam (www.trossenrobotics.com):

- Force sensor - $8.75 + shipping


Tarek & Ivan (www.mouser.com):

- Infrared LEDs (QED123) - 6 x $0.27 = $1.62
- Infrared Receiver (QSD123) - 6 x $0.28 = $1.68
- Infrared Logic Detector (QSE157) - 6 x $0.67 = $4.02

Sunday, January 18, 2009

Robots

So, I am watching the Eagles-Cards football game (and am not happy that Arizona is winning), so I figured I'd post this link:

http://singularityhub.com/2009/01/12/a-review-of-the-best-robots-of-2008/

The link says it all. Enjoy...

Thursday, January 15, 2009

Servo working with Arduino and Motor Shield


I made the servo I took from the lab work with Arduino and the Motor Shield.
I am attaching a video of it working. The code I used is pretty simple, it just goes from 0 to 180 degrees and comes back.
The servo works right with either the USB or the power adapter with no extra power to the motor shield. I don't know what will happen when we put some load into it. 



Also, I found out that when you attach the motor shield into the Arduino, all the input-output pins are in use, so I don't know how we're going to use both the input-ouptuts AND the motors. Anyone knows anything about this?

Here is the code I used:

#include <>

ServoTimer1 servo1;
int pos = 0;     // variable to store the servo position 
 
void setup() 
  servo1.attach(9);   // attaches the servo on pin 9 to the servo object 


void loop() 
  for(pos = 0;pos <>    // goes from 0 degrees to 180 degrees 
  {                                // in steps of 1 degree 
    servo1.write(pos);             // tell servo to go to position in variable 'pos' 
    delay(15);                     // waits 15ms for the servo to reach the position 
  } 
  for(pos = 180; pos>=1; pos-=1)   // goes from 180 degrees to 0 degrees 
  {                                
    servo1.write(pos);             // tell servo to go to position in variable 'pos' 
    delay(15);                     // waits 15ms for the servo to reach the position 
  } 

You can find the library ServoTimer1.h here.
Extract the rar file and copy the whole ServoTimer1 folder into the Arduino directory \hardware\libraries

Update:
In the first line of the code "#include <>"
You have to type ServoTimer1.h between the <>.
This thing won't let me post it right because it assumes it's code for the blog.


Wednesday, January 14, 2009

Weiser's hypothetical scenario of living in a ubiquitous computing world from his article in Scientific American (1991) - interesting as a reference -

Neither an explication of the principles of ubiquitous computing nor a list of the technologies involved really gives a sense of what it would be like to live in a world full of invisible widgets. To extrapolate from today's rudimentary fragments of embodied virtuality res embles an attempt to predict the publication of Finnegan's Wake after just having invented writing on clay tablets. Nevertheless the effort is probably worthwhile:

Sal awakens: she smells coffee. A few minutes ago her alarm clock, alerted by her restless rolling before waking, had quietly asked "coffee?", and she had mumbled "yes." "Yes" and "no" are the only words it knows. Sal looks out her windows at her neighborhood. Sunligh t and a fence are visible through one, but through others she sees electronic trails that have been kept for her of neighbors coming and going during the early morning. Privacy conventions and practical data rates prevent displaying video footage, but time markers and electronic tracks on the neighborhood map let Sal feel cozy in her street.

Glancing at the windows to her kids' rooms she can see that they got up 15 and 20 minutes ago and are already in the kitchen. Noticing that she is up, they start making more noise.
At breakfast Sal reads the news. She still prefers the paper form, as do most people. She spots an
interesting quote from a columnist in the business section. She wipes her pen over the newspaper's name, date, section, and page number and then circles the quote. The pen sends a message to the paper, which transmits the quote to her office.

Electronic mail arrives from the company that made her garage door opener. She lost the instruction manual, and asked them for help. They have sent her a new m anual, and also something unexpected -a way to find the old one. According to the note, she can press a code into the opener and the missing manual will find itself. In the garage, she tracks a beeping noise to where the oil-stained manual had fallen behind some boxes. Sure enough, there is the tiny tab the manufacturer had affixed in the cover to try to avoid E-mail requests like her own.

On the way to work Sal glances in the foreview mirror to check the traffic. She spots a slowdown ahead, and also notices on a side street the telltale green in the foreview of a food shop, and a new one at that. She decides to take the next exit and get a cup of coffee while avoiding the jam.
Once Sal arrives at work, the foreview helps her to quickly find a parking spot. As she walks into the building the machines in her office prepare to log her in, but don't complete the sequence until she actually enters her office. On her way, she stops by the offices of four or five colleagues to exchange greetings and news.

Sal glances out her windows: a grey day in silicon valley, 75 percent humidity and 40 percent chance of afternoon showers; meanwhile, it has been a quiet morning at the East Coast office. Usually the activity indicator shows at least one spontaneous urgent meeting by now. She chooses not to shift the window on the home office back three hours -- too much chance of being caught by surprise. But she knows others who do, usually people who never get a call from the East but just want to feel involved. The telltale by the door that Sal programmed her first day on the job is blinking: fresh coffee. She heads for the coffee machine.

Coming back to her office, Sal picks up a tab and "wav es" it to her friend Joe in the design group, with whom she is sharing a virtual office for a few weeks. They have a joint assignment on her latest project. Virtual office sharing can take many forms--in this case the two have given each other access to their location detectors and to each other's screen contents and location. Sal chooses to keep miniature versions of all Joe's tabs and pads in view and 3-dimen sionally correct in a little suite of tabs in the back corner of her desk. She can't see what anything says, but she feels more in touch with his work when noticing the displays change out of the corner of her eye, and she can easily enlarge anything if necessary.

A blank tab on Sal's desk beeps, and displays the word "Joe" on it. She picks it up and gestures with it towards her liveboard. Joe wants to discuss a document with her, and now it shows up on the wall as she hears Joe's voice:
"I've been wrestling with this third paragraph all morn ing and it still has the wrong tone. Would you mind
reading it?"
"No problem."
Sitting back and reading the paragraph, Sal wants to point to a word. She gestures again with the "Joe"
tab onto a nearby pad, and then uses the stylus to circle the word she wants:
"I think it's this term 'ubiquitous'. Its just not in common enough use, and makes the whole thing sound
a little formal. Can we rephrase the sentence to get rid of it?"
"I'll try that. Say, by the way Sal, did you ever hear from Mary Hausdorf?"
"No. Who's that?"
"You remember, she was at the meeting last week. She told me s he was going to get in touch with you."

Sal doesn't remember Mary, but she does vaguely remember the meeting. She quickly starts a search for meetings in the past two weeks with more than 6 people not previously in meetings with her, and finds the one. The attendees' names pop up, and she sees Mary. As is common in meetings, Mary made some biographical information about herself available to the other attendees, and Sal sees some common background. She'll just send Mary a note and see what's up. Sal is glad Mary did not make the biography available only during the time of the meeting, as many people do...

physical computing

Interesting and relevant book review on Stephan Wolfram's taking on the physical world as computing device.  

http://query.nytimes.com/gst/fullpage.html?res=9D02EEDA113DF932A25755C0A9649C8B63

Tuesday, January 13, 2009

Smallest transistor

#51: Physicists Build the World’s Smallest Transistor

12.12.2008

The tiny device measures an astonishing 10 atoms by 1 atom.

by Stephen Ornes

nanotransistorPhysicist Leonid Ponomarenko build graphene into a chip.

K.S. Novoselov & A. K. Geim

Smaller is better when it comes to the transistors that form the heart of modern electronics, and in April a team of European physicists reported in Science [subscription required] that they had created the tiniest transistor in history. Measuring roughly 10 atoms by 1 atom, the minute device was fashioned from graphene, an impossibly thin carbon nanomaterial.

“If you hold a sheet of graphene, you won’t be able to see it,” says Kostya Novoselov, a University of Manchester physicist who worked on the research. “It has perfect crystallized structure, but it is only one atom thick. This is the thinnest possible material in the world.”

Novoselov says the miniature transistor will be well suited for the demands of ever-shrinking electronic devices, which require a lot of power packed into a small area. Larger graphene transistors have already been shown to perform 10 times as quickly as conventional silicon transistors in the lab, although scaling that capability up to mass production may be difficult. Graphene, which is both transparent and conductive, could also be used for making liquid crystal displays. Other researchers are investigating ways to put graphene to work in solar cells.

This work suggests that the silicon age may give way to a new era of even faster, smaller, “molecular electronics.” “The ultimate goal is to use one reproducible molecule per transistor,” Novoselov says.

Books Update

Hello all,
The books will be here on Thursday the 15th. I'll update this post or put up a new one when I actually have them, so y'all can stop by my office to pick them up.

Remember, the cost is $40 ( $19.35 for the book and the rest is my handling charges). I decided to be generous and add no cost for shipping.

Se y'all tomorrow.
-Apoorva

Physical Computing Books

Does anyone own either of Tom Igo's books on physical computing?
If so, can you comment on their usefulness?

Paul.

Video Conversion Software

I figured I'd add the video conversion software I use.

http://www.nchsoftware.com/prism/plus.html

This converts to and from virtually all the codecs I know (I haven't used any particularly obscure ones yet).

It's very simple and easy to use.

Cheers,
-Apoorva

New meeting place for the class

I'm just copying the information Dr. Green e-mailed us this morning:

"Architectural Robotics will meet at 10am tomorrow (Wed.) in the Fluor Daniel Lab (259), not in Lee Hall Library.
 
This will be our meeting place from here on (unless we decide together differently)."

Monday, January 12, 2009

Arduino Article

hey all - i noticed this article today via engadget and wanted to let everyone know about it. Perhaps we could be doing this by Wednesday? :) Thanks for putting up all the info so far.

see you soon!




Info of the Arduino



Here you can read some specifications of the board we are buying (Due Mila Nove).
Dr. Walker ordered them and they should be here by Monday or Tuesday.

If the link doesn't work go to arduino.cc and navigate through all the options.

I add some information from the IMSA-research website. These are some links to guides to start using Arduino:

FOR DEVELOPING ARCHITECTURAL ROBOTICS / ARDUINO PROGRAMMING

• http://www.arduino.cc/en/Guide/HomePage
> Arduino Home Page 

itu.dk/people/sokoler/workshop/ProgrammingBooklet.pdf
> Evans, Brian, W. Arduino Programming Notebook [pdf download].

webzone.k3.mah.se/projects/lab/Folder/index.aspx?file=32&function=text
> Getting Started with Arduino - Massimo Banzi [pdf download]

• http://www.pdf-search-engine.com/arduino-pdf.html [and select “Bionic Ardiuno”]
> “Bionic Arudino” [tutorial; download from list]


Sunday, January 11, 2009

Arduino Software

Hi Robotecture men,
Here you will find a link for downloading the Arduino software for free, as you all know that it is an open source hardware. Enjoy
http://code.google.com/p/arduino/downloads/list

Thursday, January 8, 2009

Arduino Kit

Hi Robotecture men,

Have any one find what we will use for Arduino!!

Test

Servos


Guys, I've found three tiny servos in my office.
They are from a RC Plane, but quite old (I don't know if they work).
The model is "Futaba IC Servo FP-S5". I haven't been able to find a datasheet online.
But I guess it has a standard connection. I don't know the power requirements, but I think that the Arduino would be able to provide enough current to move it without load.
Before buying any servos we could just have a try with these.
I'm attaching a picture so you know what I'm talking about. Sorry about the quality... my phone's camera isn't its best feature.


Apoorva Update

Digikey has some analog servos here.

Maybe someone (i.e. Dr. Walker or Green) could proffer their opinion about these servos.

Books

I have ordered 7 copies of The Robot.

It is scheduled to ship on Monday, 12th Jan via expedited shipping so hopefully it is here before or during class next Wednesday.

Please note I accept Credit Cards and checks: I get to keep the card and prefer the check be signed but blank in the money columns.

Cheers,
-Apoorva