DuaneB:
That looks really good, well done.If anything it looks as if the servos are struggling to hold position meaning they do not have enough torque.
First find a way to check that the values you are sending are smooth, then if you want to try a higher refresh rate, let me know.
rcarduino.blogspot.com
Hi DuaneB, thanks for your reply and compliment.
I think they have enough torque, because the jitter still occured when I lift up the robot.
I'd already checked the servos values thru serial monitor before, and they appeared as they expected.
May I have your servo library please?
P.s. Great blog you have there, must bookmark it!
tuxduino:
You can zip it and add it to a post as an attachment. (Hint: additional options below the textbox)
Done tuxduino. Hope you could help me.
But I have to warn you that my code is unprofessional, all messy and I didn't put comment lines to explain what doing what since I didn't expect someone would read it in the future. Sorry 
Quadruped_FULLCODE.rar (6.47 KB)