A work under progress. A first monster for a big set of monster I want to create. This one is called NhamNham.
NhamNham lives in forests and swamps and can be quite aggressive atacking with his forehead horn.
Here in this picture they organized a attack to a village and are been repealed by soldiers.
One more version of the my free tileset for game development. This little world is beautifully growing, now towards medieval themes. Now is already possible to imagine a typical day in a little rpg village:
And here the tileset, eighth version:
Changelog:
[audio:http://cejug.podomatic.com/enclosure/2009-03-17T08_20_43-07_00.mp3]O Igo Coelho recebe neste episódio eu e o Amaury Brasil, falamos sobre o que é o CCT, PUJ e os temas do próximo encontro dia 23 de março de 2009 na UNIFOR. Apresentando o LWUIT com Daniel Valente e Introdução a programação em Java para a TV Digital com Amaury Brasil.
Fotos da gravação lá na Fortes.
Parabéns ao Igo Coelho mais uma vez pela iniciativa e a todos que contribuíram para fazer mais esse episódio do CEJUG Podcast acontecer. ;D
I got a simple motor from a broken domestic printer. It’s a Mitsumi m355P-9T stepping motor. Any other common stepping motor should fits. You can find one in printers, multifunction machines, copy machines, FAX, and such.
With a flexible cap of water bottle with a hole we make a connection between the motor axis and other objects.
With super glue I attached to the cap a little handcraft clay ox statue.
It’s a representation from a Brazilian folkloric character Boi Bumbá. In some traditional parties in Brazil, someone dress a structure-costume and dances in circular patterns interacting with the public.
Photos by Marcus Guimarães.
Controlling a stepper motor is not difficult. There’s a good documentation on how to that on the Arduino Stepper Motor Tutorial. Basically it’s about sending a logical signal for each coil in a circular order (that is also called full step).
Animation from rogercom.com.
You’ll probably also use a driver chip ULN2003A or similar to give to the motor more current than your Arduino can provide and also for protecting it from a power comming back from the motor. It’s a very easy find this tiny chip on electronics or automotive stores or also from broken printers where you probably found your stepped motor.
With a simple program you can already controlling your motor.
// Simple stepped motor spin // by Silveira Neto, 2009, under GPLv3 license // http://silveiraneto.net/2009/03/16/bumbabot-1/ int coil1 = 8; int coil2 = 9; int coil3 = 10; int coil4 = 11; int step = 0; int interval = 100; void setup() { pinMode(coil1, OUTPUT); pinMode(coil2, OUTPUT); pinMode(coil3, OUTPUT); pinMode(coil4, OUTPUT); } void loop() { digitalWrite(coil1, step==0?HIGH:LOW); digitalWrite(coil2, step==1?HIGH:LOW); digitalWrite(coil3, step==2?HIGH:LOW); digitalWrite(coil4, step==3?HIGH:LOW); delay(interval); step = (step+1)%4; } |
Writing a little bit more generally code we can create function to step forward and step backward.
My motor needs 48 steps to run a complete turn. So 360º/48 steps give us 7,5º per step. Arduino has a simple Stepper Motor Library but it doesn’t worked with me and it’s also oriented to steps and I’d need something oriented to angles instead. So I wrote some routines to do that.
For this first version of BumbaBot I mapped angles with letters to easy the communication between the programs.
Notice that it’s not the final version and there’s still some bugs!
// Stepped motor control by letters // by Silveira Neto, 2009, under GPLv3 license // http://silveiraneto.net/2009/03/16/bumbabot-1/ int coil1 = 8; int coil2 = 9; int coil3 = 10; int coil4 = 11; int delayTime = 50; int steps = 48; int step_counter = 0; void setup(){ pinMode(coil1, OUTPUT); pinMode(coil2, OUTPUT); pinMode(coil3, OUTPUT); pinMode(coil4, OUTPUT); Serial.begin(9600); } // tells motor to move a certain angle void moveAngle(float angle){ int i; int howmanysteps = angle/stepAngle(); if(howmanysteps<0){ howmanysteps = - howmanysteps; } if(angle>0){ for(i = 0;i<howmanysteps; i++){ step(i%4); delay(delayTime); } }else{ for(i=0;i<howmanysteps;i++){ backstep(i%4); delay(delayTime); } } } // tells motor to move to a certain angle void moveToAngle(float angle){ moveAngle(angle-actualAngle()); } // actual stepper motor angle float actualAngle(){ return step_counter*stepAngle(); } // angle made by each step float stepAngle(){ return 360.0/steps; } // backward step void backstep(int coil){ digitalWrite(coil1, (coil==3)?HIGH:LOW); digitalWrite(coil2, (coil==2)?HIGH:LOW); digitalWrite(coil3, (coil==1)?HIGH:LOW); digitalWrite(coil4, (coil==0)?HIGH:LOW); step_counter--; } // forward step void step(int coil){ digitalWrite(coil1, (coil==0)?HIGH:LOW); digitalWrite(coil2, (coil==1)?HIGH:LOW); digitalWrite(coil3, (coil==2)?HIGH:LOW); digitalWrite(coil4, (coil==3)?HIGH:LOW); step_counter++; } void loop() { byte val; if(Serial.available()){ val = Serial.read(); switch (val) { case 'A': moveToAngle( 0); break; case 'B': moveToAngle( 45); break; case 'C': moveToAngle( 90); break; case 'D': moveToAngle(135); break; case 'E': moveToAngle(180); break; case 'F': moveToAngle(225); break; case 'G': moveToAngle(270); break; case 'H': moveToAngle(315); break; case 'I': backstep(1); backstep(0); break; case 'J': step(0); step(1); break; } Serial.print(val); } } |
In another post I wrote how create a Java program to talk with Arduino. We’ll use this to send messages to Arduino to it moves.
[put final video here]
To be continued… :)