Reading from a Sharp GP2D120

Community General Discussions
1

Hi,

Using an ATmega8, and i'm having trouble reading from my sharp GP2D120.

Here's the code i'm using, which is from the manual of my kit:

while(1)
{
sensor=0;
for (i=0;i<5;i++)
{
sensor=(sensor+analog(0)); // Read GP2D120 5 Times
}
sensor=(sensor/5); // Average Data
if (sensor>260) // data more than 10 CM ?
{
backward(50);sleep(800); // away from object
s_left(50);sleep(600);
}
else
{
forward(50); // do not any object "Let'go"
}
}

 

so my question is why do i need to take an average over 5 readings? can't i just read it, deal with and go on?

also i was wondering if it's ok to mount that sensor vertically, as opposed to horizontally.

Thanks.

 

qin__23

2

why not add "
why not add " Serial.print(sensor);" to get the out put for the sensor…then decide whether to use the average or not

3

Averaging it will take care

Averaging it will take care of any weird fluctuations you may get and it shouldnt cause too much overhead.</p><p>If you want to detect objects moving on the horizontal plane the datasheet says that its best mounted vertically, but horizontal should work fine too.

4

I guess i’ll average it

I guess i’ll average it then.

I am currently mounting it horizontally, but i wanted to mount it vertically. Basically i want to have two sharp sensors on the left and right edge of my bot to tell in which direction i should turn: if there’s something on the right edge that’s closer, or on the left edge.

Thanks for the responses.