Those are regular PWM style servos. However, the internet googling says they need minimum of 10v to work

See my googly result here: https://forum.arduino.cc/index.php?topic=601050.0

Thanks, I saw that but manufacturer said 7.4v so I didn't want to smoke one. I guess ill grab and arduino and 10v and see what happens.

You don't need an arduino. I only found that link on an arduino website. It doesn't mean that 10v only applies to Arduino. Use 10v with your existing EZ-B v4 or IoTiny.

Max voltage of ez-robot controllers is 16v: https://www.ez-robot.com/Tutorials/Files/EZ-Bv4%20Datasheet.pdf

Pumped up the voltage and it still doesn’t work with the HDD PWM servo driver.  It is really jittery and randomly changes position. When you change position it jumps and skips so I am guessing the PWM settings are different then the standard ez-robot HDD servos but I really don’t know much about servos so I really have no idea.

EZ-Robot HDD servos use standard hobby servo pwm signal - which is standard across all hobby servos ever made... except.... apparently for these. So the question is what protocol or pwm signal do they use?

Can you find any information on these servos for their pwm or signal?

I found out watt the problem was and I amp embarrassed to say the solution.  Anyway use a LIPO LOL and the PWM driver works fine. These servos have a lot of torque.

problem closed.

he is alive and working 22DOF complete with ez-robot camera in head. going off to watch your tutorials on how to make him walk. 

Cool!! Auto Position to the rescue

This Auto Position thing for walking is harder than it looks.  First steps. I had underestimated the amps this thing would need and had to throw a drone Lipo on it to get the amps I need and then drop it back to 7.5v

Looking good so far! Little tweaks here and there and you’ll have it perfect

gaits are never easy! Think how hard it takes a child to learn to walk