So my Futaba S3004 servos are rated at appr. 60 deg. of movement.
They may very well be doing 60 deg. as I haven’t actually extracted the protractor from my 10 year old altimeter project to check. But here’s my question:
When I use the Maestro Control Center to move the servo clear to one side or the other and then disable it I’m able to turn it further with my hands. Does this mean that I’m not getting full advantage of the 60 deg. range, or is this simply designed into the servo itself so that it does not overextend itself?
You can get more range out of a servo by extending the min and max limits to something wider than the default 1-2ms. This is done on the “Channel Settings” tab of the Maestro Control Center. I recommend moving the servo slowly, underpowering it (e.g. with 4V), and carefully watching for it to hit its limits so that you avoid breaking it - most servos will destroy themselves if you try to drive them too far in either direction.
It took me a few seconds to figure it out but now I have it rotating at a little more than 180 deg.
For anyone else who’d like to try this, here’s the method I used.
Remove any actuator arms that may be attached.
Open the gearbox but leave the gears in tact. (explained later)
Open your Maestro Control Center and navigate to the Channel Settings tab.
Set your speed and acceleration both to 5.
Set your Min and Max for low and high numbers. (I used about 300 and 2500).
Click "Apply Settings"
Go back to the Status tab, plug your server into your Maestro board, and check the “Enabled” box.
Now, slowly drag the slider down. If you go too far the potentiometer may cause the gears to stick and ‘pop’ out a few of them, so be prepared for this (this is why the gearbox should be open). When this happens your servo will keep turning.
Disable the servo in the control center and fix the gearbox. Make a best guess estimate as to how low you went before it flew off, then add about 20 or more to that.
Do the same for the max value.
Put these two new Min and Max values in the configuration under the “Channel Settings” tab.
Try the Min and Max values once more and make sure the gears don’t pop out. If they do keep adjusting your values to compensate.
Put the gearbox back together.
Now, place a finger on top of the actuator arm or axle and drag the bar to the Min and then the Max. If the arm or axle stutters at either Min or Max then you may have to adjust it more in the Channel Settings.
My operating Min/Max is now set to 368-2400 even though I could probably open up that range a little. This gives me just over 180 deg. of movement.
Now that you have your Min and Max you can change your Speed and Acceleration to more preferable values. Just be sure to do the ‘Shutter Test’ once more just to verify that your final settings will not harm the servo or its gearbox.
