It plays the script fine while connected to USB but will randomly restart while running independently without the pc. It is powered by one 6v source (processor and servos). I thought it might be brownout issue but when measured, it shows only drawing 1.5A peak. What could cause this?
Hello.
A brown-out reset sounds most likely to me (especially since it works fine when connected to USB). What are you using for your power supply? It’s possible that the current draw is enough to cause the voltage to dip, and noise from the motors could be making it worse, too. Do you have access to a scope you can use to look at the VIN voltage while the system is running?
Brandon
I have an Amp/Volt meter attached at the source (12v- 3s Lipo battery) which recorded minimum voltage at 11.2V and maximum Amp draw at 1.3A during the animation. Should I power the processor and servos separately? Is it a matter of simply moving the jumper while supplying an additional power source to the servo rail?
It sounds like you switched to powering your whole system from a 3S LiPo for a test; please note that this is a higher voltage than most servos are rated for (usually 4.8V-6V nominal). Additionally, the current draw will be different with a different supply voltage, but if the setup ran without resetting with that supply, then that is more evidence that the 6V supply was dipping too low and resetting the Maestro.
To power the Maestro and servos separately, you can remove the VSRV=VIN jumper, then connect your servo supply to the servo power rail and the Maestro logic supply to the VIN pin on the Maestro. You can find more information about this in the “Powering the Maestro” section of the Maestro user’s guide under the “Two power supplies” heading.
Brandon
I forgot to mention the 12v source was stepped down to 6v when powering the board. I’ll give the separate power method a try.
With that information, it seems likely that your power supply (the LiPo battery) is probably not the problem, but your step-down regulator might not be able to handle the current draw. If you want to troubleshoot that further, could you post some information about the step-down regulator you are using?
Brandon
It’s a Turnigy SBEC Switching BEC, Input 26V max, Output 5/6V selectable, Max current 5A. I suspect this to be the culprit too and have ordered a Castle Creation 10A BEC. Will try it and report back. Here’s the animatronics when it is running smoothly via USB + external power.
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@BrandonM , you are right. I replaced the BEC with a 10A model and everything runs smoothly using a single power source. My mistake was reading the current consumption at the 12V source before it was stepped down to 6V. Thank you for your help.
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