I am looking in to building a 3 servo controlled unit. I have so far decided to use the M51660L chip to control the DC motors with a remote potentiometer.
The problem is, I require all 3 motors to have reached there required location, before the next location is sent.
Is there any way to get a feedback to let me know when the motor has stopped/reached is location?
I know this can be done with timing, but each motor will reach there location at different times, and I want it to pause each motor till all 3 are done.
I have strong electrical knowledge, but this has just got me stumped.
thanks in advance.
A few ideas to consider…If
A few ideas to consider…
If you need precise control, would you be better off with stepper motors, where you can control exactly where each motor is?
If you stick with servos, you can do a few things. One is to allow for some time to pass between servo position commands before you issue the next. You could use simple delay statements, but that is messy. Instead you can set a timer and use varibles to keep track of when you issue a command, then wait a pre-determined period before proceeding to the next change.
You can even vary the amount of time you wait, based on the biggest move of the three servos.
Example (Arduino code):
long previoustime = 0; // keep track of previous millis value for timing
long waitinterval = 1000; // initialize wait interval; this can be changed later based on how long you need
void loop()
{
unsigned long currentMillis = millis();
if(currentMillis - previousblintime > waitinterval) {
previoustime = currentMillis;
waitinterval = 2000; // Or use a calculation based on how far your servos have to move.
// DO STUFF - Like move your servos
}
Servo
You can buy (or mofify) servos with the wiper feedback signal bought out on a separate wire. See Adafruit.
The “better” method is what ignoblegnone proposed, stepper motors.
A third option would be put a current sensor in series with the power to the servo’s and monitor the current consumption.
**Servo current **
If you measure the current to the servo you can tell if its still moving.
rg
OOPS… Read first post second. ggallant’s third option is how i would do it.
Sorry for the unnecessary post guys.