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Asked — Edited
Resolved Resolved by Jeremie!

Continuous Rotation Servo Speed

Is there any way to control the speed of the continuous rotation servo's from the developers kit via the mobile interface?

I tried a few different controls but none seem to work.
I also tried the servo speed command

They move like their trying to win a speed race.

Thanks

#1  
You should be able to adjust via "PWM (digitalPort, speed)" in the script configuration of a given directional control. So if you add a forward button, add PWM script controls for both drive motors and set the speed.

You could add a second set of controls for another speed level. One set for fast. One set for slow.
#2  
Thanks for the answer.

By PWM control do you mean the PWM slider control?

I tried that and got some reaction from it but it's going from super fast at a specific duty cycle to super slow, to reverse.

The servo speed control does nothing.

Thank
#4  
@Darathian - no, not the slider control. Try this, add a forward button. Then select the button...and off to right do you see where it says "On Pressed Script" and by default it says "Forward()". Well next to that is a pencil icon. Click on the pencil. This opens up the script interface...now you have to make a script and add "PWM (digitalPort, speed)" . You'll need two script lines one for your right and left drive motor.

@Richard I don't think there is Modified servo Movement Panel in the mobile interface. Unless its hidden? I bet you guys hide it in my version :P
#5  
Ok, just figured he might get it working in ARC before trying to move it to his Android device...
PRO
Canada
#6  
Hey guys, I just did a little test this morning which will help everyone trying to slow down their 360° Servos.

Using the "Modified servo Movement Panel" Control, in the settings enable the "use" check box beside the Stop value. You will then likely have to change your Stop values from the default value of 89 to something else. Take the opportunity to save your changes and then test them by clicking on the directions and stop buttons within the Modified servo movement panel. Then adjust the Forward and Reverse values to be close to the center value of your servos in order to slow the servos down, the closer to the stop value they are the slower the servos will go.

Here's the settings I used:

User-inserted image


Keep in mind your servos may be slightly different on the center ("stop") values than my example due to the nature of 360° Servos (different potentiometer values). You also may have to tweak the forward and reverse values on the servos to keep your robot tracking straight. Servos often spin faster one way than the other so when you use 2 x 360° Servos mounted in opposite directions they naturally tend to make the robot favor turning instead of going straight. One direction will be of a value further away from the stop value than the other.

I can confirm that once these settings are saved they work in the mobile interface as well.:)
#7  
@Jeremie Please note that this is for v4 servos from the development kit NOT v3 servos. I tried setting on version 3 servos, works very very slow...

John
#8  
The numbers for the V3 kit servos are different, but the concept is the same. The speed is controlled by the forward and reverse values. I had to set mine to different values because one of my servos spins a little faster than the other so my bot would slowly go in circles (and of course, they are backwards from each other when actually mounted on a bot, so you would flip the forward and reverse values for left and right servo).

Alan
#9  
First thank you for all the replies.

I tried Jeremie's advice and it seemed to worked mostly. I only had time to test on a single servo on D0.

My stop value ended up being 108.

However I noticed something odd I have not yet been able to pin down.

1. Sometimes their seem to be a very slight delay between hitting stop and the servo actually stopping all the way. Slight vibration in the servo but the wheel does not seem to move and then the servo goes completely silent.

2. It almost seemed like I had some drifting on the stop value. Sometimes after resetting the EZB I would have to adjust the stop one up or one value down. However I am recharging the batteries just to make sure they weren't playing a role. More testing is needed on my side.

I will also try the scripting methods provided since eventually I would want to script this so I can control the speed at any time.
#10  
What is the function of the servo speed control and what is the use cases. I ask since in my case it made no difference in speed on 360° Servos.

Thanks
#11  
Speed control on normal servos is very useful. Panning cameras slowly or a when used as an arm linkage (moving an arm into position).... High speed arm movements makes it look like the robots arm is flailing.... Slowing servos down helps with more precise movements in many cases.... Gives robots like JD and Six the ability to walk or run so to speak....
United Kingdom
#12  
Servo Speed doesn't affect modified servos which is why it made no difference. Following Jeremie's advice should aid you in setting up the modified/360 degree servo's speeds.
#14  
I'm new to the forum, so I'm not sure how to give credit for good advice.
Thanks for your help.
Special thanks to Jeremie for his excellent explanation.
If there is a thumbs up button, please let me know.
#15  
@Pilgrimgary,

If you post a new topic, and mark it as needing assistance, then you will be able to give credit to anyone who answered your question. Only use it if you really need assistance though, and not just for general conversation or simple questions. The person awarded credit for the answer earns store credit in the EZ-B shop (currently $3 per answer ) so there are some terms of service around its use.


There is no general "thumbs up" function, although a thank you post like you did is just as good.

Alan
Alan
#16  
@pilgrimgary You can only give credit when it's a thread you started...