Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: Ro-Bot-X on December 11, 2007, 06:20:03 AM

Title: Encoder calculator
Post by: Ro-Bot-X on December 11, 2007, 06:20:03 AM
I have some trouble with the results of the Encoder calculator.

I am using cont rotation servos, so RPS (RotationsPerSec) is 1 beacuse RPM is 60. Wheel diameter is 51mm so wheel circumference is 51*3.14=160.14 mm. Let's say it's 16 cm. I need to go 0.5 cm per click, so 16/0.5=32 clicks.

This is the data I have entered:
Robot Velocity = 0.16 m/s (160 mm/s)
Wheel Diameter = 0.051 m (51 mm)
Clicks on Wheel = 32 clicks
Espected slip = 0 %

Now this is the data I got:
Distance per click = 0.0209 cm ????? how come?
Seconds per click = 0.00131 ???
Clicks per second = 764 ???

If the wheel rotates once every second and there are 32 clicks in one rotation, there should be 32 clicks per second!

What am I doing wrong?
Title: Re: Encoder calculator
Post by: cooldog on December 11, 2007, 06:28:33 AM
i haven't use the encoder calculator but by the sound of it:


Now this is the data I got:
Distance per click = 0.0209 cm ????? how come?
Seconds per click = 0.00131 ???
Clicks per second = 764 ???


distance per click= how far it will go before it reads another line on the encoder
seconds per click= how many seconds it takes between each line on the encoder
clicks per second = how many clicks in one second if the motors are running at the speed you inputed.

i hope this helps
Title: Re: Encoder calculator
Post by: Ro-Bot-X on December 11, 2007, 06:37:01 AM
Yeah, but my calculations don't mach with the calculator's calculations. I want to know which is the correct answer.
Title: Re: Encoder calculator
Post by: cooldog on December 11, 2007, 06:40:15 AM
sorry

tis is a question for admin maybe the sode is wrong for the caculator or maybe you didn't caculate right
Title: Re: Encoder calculator
Post by: Admin on December 11, 2007, 09:06:09 AM
oops!

looking at my source code, I have this:
circumference=Math.PI*radius*radius;

obviously its wrong . . . not sure how that got there . . .

I'll fix it when I get home from work . . . sorry!!!
Title: Re: Encoder calculator
Post by: Admin on December 12, 2007, 05:24:41 AM
It should be fixed now.

Let me know if you find anything else that isn't right . . .