I am needing some help with worm gear ratios and whether or not to use a hexial <(made up word) incline. I am also looking for help with using 2 servos in tandem driven by a honey pot.
If interested I have several more details but this is a project i am looking to take to market and may have you’s sing a NDA.
If you’re looking for boilerplate NDA text I’d suggest an internationally harmonized agreement 
Since he’s having you SING an NDA an internationally HARMONIZED agreement makes since. 
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Lol, yeah. That’s where I was going. I don’t even think an internationally harmonized NDA is a thing but it sounded good 
OMG! what a type-O thank you all for the humor of my error really made my day! In all seriousness though I do need some help. If anyone would like to meet up for Choir practice and forgo signing a NDA. I am sure we can all benefit from the harmony!
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Worm gears generally demand that you use a “helix” gear config, otherwise the wear and lash get ugly.
2 servos to drive a “honey pot”…what exactly is a honey pot?
I have considered a “bevel gear” as well as a “helical gear”* to drive an object open and closed I am looking at space and low profiles./ The honey pot i am referring to is a potentiometer. I will not be able to apply very much force due to space constraints but a minimum i would like to have at least 4.4 NM of force.
Say an average worm gear with 40:1 reduction, helix final, 80% torque transfer… For 4.4 Nm, you’ll need a single servo with 0.1375 Nm of torque.
What is the 2nd servo motor for?
I want to use the the 2nd servo motor (thinking out loud- for the same thing to open and close both objects at the same time. Like shutters for instance) but i want to only use 1 source to control both. I know this can be done with a PI or other Micro control although i was hopping to avoid that to keep cost down. I was also considering a 3-way switch but i have not been able to put this to the test… yet
I have a lot of questions about gears. but i am not familiar with the lingo enough to ask the right questions
These microcomputers are dirt cheap now, ~$4 for a Arduino Nano.
An ESC is cheap, so is an H-bridge chip.
A brushless DC Servo motor is a 3 phase device. To reverse a DC Servo, you have to switch 2 of the phases, which is why you need an H-bridge.
An ESC (the main driver for a DC Servo) runs at a base frequency. When you send it a shifted frequency, it turns the motor. To get it to reverse, you send a signal to the H-bridge, which swaps the signal to 2 of the wires.
Is this what you are looking to do?
DC_Servo_H_Bridge.pdf (10.4 KB)
yes that solves the first half of one of my problems. Do you know if i can give the same signal from the same H-bridge to 2 servos at the same time? or do they need to each be stand alone?
I think i will do some research on the the H-Bridge. Thank you for your help!
You’re welcome.
You can do the same thing with a DC motor, using only an H-bridge. But, DC motors don’t have near the power/weight ratio of the brushless DC servos they make today.
You can simply re-purpose a cordless electric drill, if all you need is Forward/Reverse with a lot of torque, geared down.