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Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

motorsformakers.com

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Re: Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

#41

Post by iancmceachern »

_spduchamp wrote: post #33

If you are looking for a super easy way to put a motor with closed loop motion control, I highly recommend Vertiq ( https://www.vertiq.co/ ) modules. They have a built-in position sensor and microcontroller. They have firmware based anti-cogging for smooth motion. I use them in making computer controlled musical instruments by just hooking up the serial interface to an ESP32 and using the Vertiq API to handle all the…

Another product in this vein, Teknik motors. They're fully integrated, give them power and Connect to them via USB amd program it. Once you program it you can just use the gpio pins on the motor to wire up switches or other types of control. Super easy

Re: Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

#42

Post by iancmceachern »

dekhn wrote: post #37
_spduchamp wrote: post #33

If you are looking for a super easy way to put a motor with closed loop motion control, I highly recommend Vertiq ( https://www.vertiq.co/ ) modules. They have a built-in position sensor and microcontroller. They have firmware based anti-cogging for smooth motion. I use them in making computer controlled musical instruments by just hooking up the serial interface to an ESP32 and using the Vertiq API to handle all the…

Do you know if this would be appropriate in, for example, a microscope stage? I use steppers (open loop) to move a stage on bearings, and I would prefer to have closed-loop with position sensing (not movement- actual position- because a single dropped step will ruin an acquisition). I already work with ESP32 and have done closed-loop DC motor stuff before, so I'm just curious if this is something I could drop in and…

Yes it would

Re: Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

#43

Post by iancmceachern »

rq1 wrote: post #20

Does anybody have an address where to shop servos and gearboxes online? Or at least find references through filtering for specific torque/rpm/power/driver resolution... etc.? I hardly can find something worth looking at outside of ebay. A lot of websites don't have public price lists but ask you to fill forms and receive quotes, but I don't want to order thousands of these (yet?)...

I second teknik motors, also check automation direct,misumi, or even ebay/Ali express

Re: Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

#44

Post by doctorwho42 »

FatActor wrote: post #38

One problem I always run into with rotary motion: gearing. Finding gears of the right diameter, thickness, and thread pitch is always such a stumbling block for me. Most sites that sell gears to fit their motors have a small selection, and sites that sell gears are very hard to navigate (only to find out they don't sell in quantities <1,000 units). I end up having them laser cut out of HDPE online. Wish there was an…

It really comes down to the fact that gear shaping/cutting machines are quite specialized machines. Therefore demand a higher cost to buy (machines cost) and setup (tooling cost).

For example a single gear shaper cutter is on average $700-$1000, and that's for a pretty standard and brand new cutter.

So without taking into account actual time to set up the machine, program it, and feed it material. You are already having a high overhead. So the only real way to deal with that cost is in volume or cost.

But when looking at the hobby market, volume is out of the question (who wants to buy >1000 of one gear for a personal project) and cost is out of the question ( if it's so expensive, I might as well 3D print or laser cut or waterjet some)

So it's an odd market to get into.

Re: Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

#45

Post by abakker »

FatActor wrote: post #38

One problem I always run into with rotary motion: gearing. Finding gears of the right diameter, thickness, and thread pitch is always such a stumbling block for me. Most sites that sell gears to fit their motors have a small selection, and sites that sell gears are very hard to navigate (only to find out they don't sell in quantities <1,000 units). I end up having them laser cut out of HDPE online. Wish there was an…

Belt drives are also very annoying. Naming conventions are inconsistent and obtuse. Parts materials differ, and a whole lot of stuff seems to be custom.

in Servos and steppers, there are also weird mixes of metric and standard sizes - e.g. Nema 34 motors often have 1/2" (12.7mm) shafts with 5mm keyways. No idea why.

Finding gears or pulleys for my purposes has 100% of the time resulted in some machining and lathe work to take off the shelf parts and make them work for my applications.

Re: Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

#46

Post by abakker »

doctorwho42 wrote: post #44
FatActor wrote: post #38

One problem I always run into with rotary motion: gearing. Finding gears of the right diameter, thickness, and thread pitch is always such a stumbling block for me. Most sites that sell gears to fit their motors have a small selection, and sites that sell gears are very hard to navigate (only to find out they don't sell in quantities <1,000 units). I end up having them laser cut out of HDPE online. Wish there was an…

It really comes down to the fact that gear shaping/cutting machines are quite specialized machines. Therefore demand a higher cost to buy (machines cost) and setup (tooling cost). For example a single gear shaper cutter is on average $700-$1000, and that's for a pretty standard and brand new cutter. So without taking into account actual time to set up the machine, program it, and feed it material. You are already hav…

standard gear cutting arbors aren't that expensive, but are often for standard module gears and the gear form is an approximation that applies to a given range of gears.

e.g. https://www.amazon.com/EVNSIX-Involute-Cutters-Milling-Machi...

Re: Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

#47

Post by iancmceachern »

abakker wrote: post #35
Youden wrote: post #32

Earlier quoted context omitted.

Assuming you're talking about AC servos typically used for industrial equipment (and not the DC kind used for robots or RC aircraft), there are kind of two routes you can go. On the easy hobbyist route, you can get the parts from a nice online store with email support like DamenCNC [0]. You'll need to read the spec sheet to find the speed/torque/resolution though. On the harder route, you collect a bunch of spec shee…

I'll say for completeness here (having mentioned Clearpath servos in another comment) that DC clear path servos are totally fine for "semi" industrial uses. I have them on a bed mill I am restoring, and with a good ballscrew I can easily move a 300lb Z axis at 200inches/minute without torque saturation. That said, they are simple because they are limited. They give you only 3 inputs: Enable, Step, Direction. they giv…

I agree, love their motors for simple applications where you don't want to write software

Re: Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

#48

Post by mstudio »

FatActor wrote: post #38

One problem I always run into with rotary motion: gearing. Finding gears of the right diameter, thickness, and thread pitch is always such a stumbling block for me. Most sites that sell gears to fit their motors have a small selection, and sites that sell gears are very hard to navigate (only to find out they don't sell in quantities <1,000 units). I end up having them laser cut out of HDPE online. Wish there was an…

I came here to say exactly the same thing. I'd love to find a kit or gearbox than can gear up/down a simple stepper motor for Arduino projects. The HDPE laser cut is a good idea though, I'll give that a try.

Re: Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

#49

Post by Animats »

FatActor wrote: post #38

One problem I always run into with rotary motion: gearing. Finding gears of the right diameter, thickness, and thread pitch is always such a stumbling block for me. Most sites that sell gears to fit their motors have a small selection, and sites that sell gears are very hard to navigate (only to find out they don't sell in quantities <1,000 units). I end up having them laser cut out of HDPE online. Wish there was an…

Stock Drive Products and Berg are the classic US small gear, bearing, and accessories suppliers. I've used those two. KHK (Kohara Gear Industry Co., Ltd, Japan) is now active in the US.

The classic Boston Gear Gearology course is no longer online at Boston Gear, but there's a copy here.[1] This gives a quick overview of the minimum you need to know about specifying gears.

[1] https://www.me.psu.edu/sommer/me360/gearology.pdf

Re: Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines (2015)

#50

Post by jakzurr »

diydsp wrote: post #28
abakker wrote: post #22

Earlier quoted context omitted.

This advice is not good. Robot arms should use harmonic drive gearboxes and servos, IMO. In practice, if the loads are not massively high, the important thing is closed loop steppers or servos, with accurate homing routines and good error handling.

Agreed. It sounds like a junior engineer bs-ing an interview after reading lots of amateur forums.

Maybe they really did ask chatgpt?
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