Author Topic: Servos are running slow  (Read 1704 times)

0 Members and 1 Guest are viewing this topic.

Offline Its_FridayTopic starter

  • Jr. Member
  • **
  • Posts: 31
  • Helpful? 0
Servos are running slow
« on: February 11, 2009, 07:46:19 PM »
I am using the axon microcontroller. When i plug in one servo, it runs at a decent speed. But when i plug in a second servo, for 1 second they run at normal speed, but then they slow down. They maintain that slower speed.

Why can one servo run fast, but 2 servos can't? They're hooked up to the microcontroller, and the microcontroller is hooked up to a 7.5 volt battery pack. My best guess is that the batteries can't provide the needed amperage. Whatever the problem maybe, how can i fix this? ???

Offline Jdog

  • Robot Overlord
  • ****
  • Posts: 259
  • Helpful? 3
Re: Servos are running slow
« Reply #1 on: February 11, 2009, 07:58:45 PM »
Try plugging in the 2 servos and measure the voltage of another output port, turn on the axon and see if there is a drop in voltage. If not Try it with a different battery pack and see if it still happens. You could even use a cheap $2 4 AA holder battery pack and try that. I know that 4 AA batteries definitely has enough amperage so try that and report the results. If that doesn't work, try writing a program to control three servos and read one adc port and print out the data, plug in your two servos and make a jumper wire from the signal wire of the other servo port to the input wire of the adc port and analyze the signal with the SOR Scope.

Offline Admin

  • Administrator
  • Supreme Robot
  • *****
  • Posts: 11,659
  • Helpful? 169
    • Society of Robots
Re: Servos are running slow
« Reply #2 on: February 11, 2009, 11:26:48 PM »
Quote
the microcontroller is hooked up to a 7.5 volt battery pack
what type of battery, and whats the mAh on it? is the battery fully charged?

Offline Its_FridayTopic starter

  • Jr. Member
  • **
  • Posts: 31
  • Helpful? 0
Re: Servos are running slow
« Reply #3 on: February 12, 2009, 02:13:49 PM »
Quote
the microcontroller is hooked up to a 7.5 volt battery pack
what type of battery, and whats the mAh on it? is the battery fully charged?
It's a 7.5V 1200 mAh NiMH Battery Pack

Offline Admin

  • Administrator
  • Supreme Robot
  • *****
  • Posts: 11,659
  • Helpful? 169
    • Society of Robots
Re: Servos are running slow
« Reply #4 on: February 12, 2009, 08:02:15 PM »
Hmmm what servos are you using?

This battery should be enough . . . is it fully charged?

Are you controlling the servos through the ADC pins or the non-regulated pins?

Offline Its_FridayTopic starter

  • Jr. Member
  • **
  • Posts: 31
  • Helpful? 0
Re: Servos are running slow
« Reply #5 on: February 12, 2009, 09:02:14 PM »
I figured out the problem.The battery is no good. Even though i measure it at 7.5V right out of the charger, it can't last more then a minute when running the servos. Thankfully i bought a spare battery that works properly.

 


Get Your Ad Here