InfoHole » Robotics http://www.infohole.com/blog A blog by Gordon Page Tue, 04 Oct 2011 05:44:40 +0000 en hourly 1 http://wordpress.org/?v=3.1.3 Verifying Integrity Of 9DOF Data Sent To Arduino Mega http://www.infohole.com/blog/robotics/verifying-integrity-of-9dof-data-sent-to-arduino-mega/ http://www.infohole.com/blog/robotics/verifying-integrity-of-9dof-data-sent-to-arduino-mega/#comments Tue, 14 Jun 2011 05:40:37 +0000 admin http://www.infohole.com/blog/?p=413 In this video I show you how I verify the integrity of data being sent from the 9DOF (9 degrees of freedom) to an Arduino Mega. The only reason for doing this is to ensure that a poor cable connection does not result in the Arduino using corrupted or incorrect X,Y,Z data (which could be catastrophic for a flying craft).

Here's my code for receiving the 9DOF data and checking it, there may be bugs, use at your own risk!


float processByteToVal(int positionInArray, byte theData, float currentTotal)
{
float newData=(float)(theData-48);//turn a byte of 49 into a number of 1, byte of 54 into int 6, etc.
float outputValue=0;

if(positionInArray==0)
{
outputValue=currentTotal+(newData/100);
}
else if(positionInArray==1)
{
outputValue=currentTotal+(newData/10);
}
else if(positionInArray==2)
{
outputValue=currentTotal;
}
else if(positionInArray==3)
{
outputValue=currentTotal+newData;
}
else if(positionInArray==4)
{
if(theData==45)//the original byte passed was a minus sign;
{
outputValue=0-currentTotal;
}
else
{
outputValue=currentTotal+(newData*10);
}
}
else if(positionInArray==5)
{
outputValue=currentTotal+(newData/100);
if(theData==45)//the original byte passed was a minus sign;
{
outputValue=0-currentTotal;
}
else
{
outputValue=currentTotal+(newData*100);
}
}
else if(positionInArray==6)//positionInArray 6 can only ever be a negative sign
{
if(theData==45)//the original byte passed was a minus sign;
{
outputValue=0-currentTotal;
}
}
return outputValue;
}

int getData()
{
int inByte;
int dataFound=0;
while(dataFound<1)
{
if(Serial3.available())
{
inByte = Serial3.read();
return inByte;
dataFound=1;
}
else
{
//delay(1);
}
}
}

void getAttitude() {
int inByte=0;
Serial3.flush();

while(inByte!=58) // 58 is :
{
inByte = getData();
}

//XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
//XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
//XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
inByte = getData();
int xPos=0;
float xVal=0;
byte xData[7];
while(inByte!=44) // 44 is ,
{
if(inByte!=-1) // -1 is not available
{

xData[xPos]=inByte;
xPos++;
}
inByte = getData();
}
int newPos=0;
xPos--;
while(xPos>=0)
{
xVal=processByteToVal(newPos, xData[xPos], xVal);
xPos--;
newPos++;

}

//YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY
//YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY
//YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY
inByte = getData();
int yPos=0;
float yVal=0;
byte yData[7];
while(inByte!=44) // 44 is ,
{
if(inByte!=-1) // -1 is not available
{

yData[yPos]=inByte;
yPos++;
}
inByte = getData();
}
newPos=0;
yPos--;
while(yPos>=0)
{
yVal=processByteToVal(newPos, yData[yPos], yVal);
yPos--;
newPos++;

}

//ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
//ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
//ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
inByte = getData();
int zPos=0;
float zVal=0;
byte zData[7];
while(inByte!=44) // 44 is ,
{
if(inByte!=-1) // -1 is not available
{

zData[zPos]=inByte;
zPos++;
}
inByte = getData();
}
newPos=0;
zPos--;
while(zPos>=0)
{
zVal=processByteToVal(newPos, zData[zPos], zVal);
zPos--;
newPos++;
}

//TOTAL - TOTAL - TOTAL - TOTAL -TOTAL
//TOTAL - TOTAL - TOTAL - TOTAL -TOTAL
//TOTAL - TOTAL - TOTAL - TOTAL -TOTAL
inByte = getData();
//Serial.println ("");
//Serial.print("This is total: ");
int totalPos=0;
float totalVal=0;
byte totalData[7];
while(inByte!=13) // 44 is ,
{
if(inByte!=-1) // -1 is not available
{

totalData[totalPos]=inByte;
//Serial.print(inByte, BYTE);
totalPos++;
}
inByte = getData();
}
newPos=0;
totalPos--;
while(totalPos>=0)
{
totalVal=processByteToVal(newPos, totalData[totalPos], totalVal);
totalPos--;
newPos++;

}
// Serial.print("totalVal is: ");
// Serial.println(totalVal);

float localTotal=xVal+yVal+zVal;

if((abs(totalVal)-abs(localTotal)<=0.03) && (abs(totalVal)-abs(localTotal)>=-0.03))
{
currentXAngle=0-xVal;//currentXAngle and currentYAngle are the gloabl variables that store the current x,y,z that we use throughout the code.
currentYAngle=yVal;
currentZAngle=0-zVal;

//FOR DEBUG PURPOSES ONLY, MUST REMOVE BEFORE FLIGHT!!!!!!!!!!!!!!!!!!!
//currentXAngle=0;
//currentYAngle=0;
imuSuccesses++;
}
else
{
Serial.println("-------------------------The data is NOT NOT NOT NOT NOT NOT valid!!!!!!------------------");
Serial.println("");
imuFailures++;
}
}

]]> http://www.infohole.com/blog/robotics/verifying-integrity-of-9dof-data-sent-to-arduino-mega/feed/ 0 Arduino Mega 2.4Ghz R/C Receiver Code http://www.infohole.com/blog/robotics/arduino-mega-2-4ghz-rc-receiver-code/ http://www.infohole.com/blog/robotics/arduino-mega-2-4ghz-rc-receiver-code/#comments Tue, 13 Jul 2010 07:29:16 +0000 admin http://www.infohole.com/blog/?p=310 Since posting this video, a few people have been asking for the source code. I don't have that exact code available still, but here is some code which takes 3 input values from an R/C receiver and outputs them to the screen.

I took this code from another of my projects, and just deleted all the non-relevant code. I may have inadvertently deleted parts of the code that I shouldn't have, so if you have come across any errors just leave a comment below with details and I'll fix it.

#include

//these store the current transmitter positions/values
unsigned long transmitterThrottlee=0;
unsigned long transmitterLeftRight=0;
unsigned long transmitterForwardBack=0;

void setup()
{
pinMode (8, INPUT);
pinMode (9, INPUT);
pinMode (10, INPUT);

Serial.begin(57600);
Serial.println("Done with setup");
}

void checkTransmitter()
{
transmitterThrottlee = (pulseIn (9, HIGH, 100000))/10; //read RC channel, wait max of 0.1 seconds for pulse
transmitterLeftRight = (pulseIn (8, HIGH, 100000))/10; //read RC channel, wait max of 0.1 seconds for pulse
transmitterForwardBack = (pulseIn (10, HIGH, 100000))/10; //read RC channel, wait max of 0.1 seconds for pulse
}

void loop()
{
checkTransmitter();//check the data being received by the transmitter.
Serial.print ("data: ");//if we decrease altitude we should check for landing, and slow our decent when we get close to the ground.
Serial.println (transmitterThrottle);
Serial.println (transmitterLeftRight);
Serial.println (transmitterForwardBack);

delay (200);
}

]]> http://www.infohole.com/blog/robotics/arduino-mega-2-4ghz-rc-receiver-code/feed/ 6 Robot Balancing On A Ball http://www.infohole.com/blog/robotics/robot-balancing-on-a-ball/ http://www.infohole.com/blog/robotics/robot-balancing-on-a-ball/#comments Thu, 06 May 2010 02:22:10 +0000 admin http://www.infohole.com/blog/?p=308 Here's a cool video of a robot balancing on a ball. Presumably it uses a few gyroscopes, magnetometers, etc.

[See post to watch Flash video] ]]> http://www.infohole.com/blog/robotics/robot-balancing-on-a-ball/feed/ 0