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Mouth Movement With Speech

I've been investigating switching my InMoov robot over to ez-robot control. I'm liking what I've seen so far. Question; Is it possible to make the mouth of a robot move in sync with speech/sound with ez-robot software? Thanks, Bob

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Yes, there is a control in ARC which moves servos based on streaming audio activity of the EZ-B v4


Great! I think I'm going to order a couple of boards and maybe a Six robot. Is the shipping time realty 5 - 7 weeks? What if I drop buy your shop, can I buy everything there?


BHouson, the parts are being manufactured and assembled right now. They are drop shipped from our manufacturing facility directly to you. There is no inventory in our office, sadly. All we have at the office are 3D printed prototypes and hand soldered prototypes.

#4 I would try and adjust the servo speed with Servospeed() command. It could be that a script or action may have taken over and is setting the servo speed to a value that is faster than needed.

It's something that I've had to get used to when writing scripts and actions for the v4 as my different animations (actions) usually run at different speeds. I have to reset the speed for most of my scripts to "0" at the beginning to make sure that one script isn't effecting another.


The servo Sound (EZ-B v4) control does not use actions or positioning - so you will not need to worry about that, unless you have specified servo speeds somewhere else.

The control that Anthony and the original poster is referring to is the servo Sound (EZ-B). The control will use the audio that is being streamed to the EZ-B v4 to move the servo. The settings are Refresh and Gain. The Refresh speed is how often the audio is sampled to move the servo. The Gain is how much the volume is amplified when converted to servo positions.

Those two numbers will need to be changed.

If you are sending an MP3 file of music, you cannot expect the servo to move with the vocal - because the music is a giant chunk of audio.

You can use the EZ-Script command SAYEZB() to speak audio, and the audio will be streamed through the EZ-B v4 and the Sound servo (EZ-B) will move the servo to the audio

United Kingdom

@DJ please correct me if I am wrong since I am assuming based on only what I can see my end and with no EZ-B V4 to test with I'm working slightly blind.

If it's like the PC sound servo it sounds like servo speeds may need adjusting along with the bits DJ mentioned.

If the servo isn't moving correctly then I'd say look at the gain, the servo moves relative to the volume of the audio. If the gain is too low it will barely move, if too high it'll move high and stay there.

I presume it's along the same lines as the bar on a graphic eq. display, when high the servo moves higher, when low it moves lower. If you set up the gain incorrectly it may remain either too low and barely move or too high and barely move.


Maybe slow down the speech - because the sound of the word Hello may be too quick for the servo to respond.