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Servo Full Range

Hey all… I am running the Maestro Mini 12… when I hook up a servo tester to any of my servos, I can get a full 180 swing… but when I control them from the Maestro IDE, moving the sliders, I get about a 45 swing of movement… kind of like the IDE truncates the movement… what am I missing… also from time to time the servos will stop responding to the sliders, if I unhook the Maestro and hook it back up, it is fine for a few minutes and they stop responding again… the USB is plugged in and the board is getting a 5V power for the servos… thoughts? thanks

Hello.

I moved your post to the “Servo controllers and servos” section of the forum since it seemed more appropriate.

By default, the Maestro limits the pulse width output of each channel between 992μs and 2000μs. I suspect your servo tester is sending signals outside of this range. If you want to send pulse widths outside of this range with the Maestro, you have to first extend the valid range by adjusting the Min and Max settings for each servo channel in the “Channel Settings” tab (the sliders in the “Status” tab will update in relation to that change). However, please note that it is possible to damage a servo by commanding it to a position that is beyond its physical limits; you can find more details and a method for safely extending the range in the “How do I use my Maestro servo controller to get the maximum possible range of motion from my servo?” entry under the FAQs tab of the Maestro product page.

I am not sure what might be causing your servos to stop responding; that sounds like a strange problem. Could you post pictures of your setup that show all of your connections as well as more information about your system (i.e. the specific servos you are using, how many you are using, and what your 5V supply is)? Can you reliably reproduce the problem by doing something specific (e.g. move a servo quickly, enable many servos at once, leave it idle for some amount of time)? Also, is the amount of time before becoming unresponsive always the same?

Brandon

what servo brand do you recommend to use, and i generally use one servo at a time… also what is the best way to ensure the servo is in an off state after a script runs from Maestro… as for power, it is just 5V to the board then using the jumper pin… nothing specific, just moving them with the sliders on the IDE… my tester is not moving the servo past it’s ability, as I can even turn the servo by hand on the hub from 0 - 180 degrees, as my tester does, but the maestro barely allows it to move in a 45 degree full sweep

I do not have any specific recommendations for a brand of servo, and in general what servo is most appropriate will likely depend on your specific application. Servo datasheets typically list an operating travel range over the standard 1-2ms pulse width range as well as a maximum travel range over an extended pulse width range. The maximum range can vary sometimes from unit to unit, but most standard servos do not guarantee more than 165°. Since your particular servo is getting 180° from your servo tester, you should be able to get the same range by extending the Maestro’s signal. As I mentioned in my previous post, you can change the allowable range in the configuration settings under the “Channel Settings” tab of the Maestro Control Center.

It sounds like you do not want the servo to continue holding it’s position after the script has finished. If this is the case, you can try setting that servo channel a target position of 0, which will disable the output from the Maestro. On some servos, this will cause them to no longer hold their position, so if it works you can end your script with a SERVO command that sets the target to 0. However, please note that some digital servos will continue to hold their last position when they stop receiving signals.

Brandon