Is it possible to reduce the step size if we replace the rotor and stator having different no of teeth? say 72 rotor teeth and 70 stator teeth will we get a step angle of 1.25 deg?
The clarity of the explanation reflects the depth of your knowledge. Your graphics team has worked hard too. You deserve every penny you get. Well earned!
I have worked on many industrial robots at an automotive company, All used servo motors with encoders attached and harmonic drives. The harmonic drive is a very high ratio speed reducer and doesn't use gears so there is almost no play, The encoder is hooked directly to the motor shaft, it consist of a thin wheel with small perforations and a led on one side and light detection on the other. As the motor turns the light going through the perforations are read and counted. So when the robot goes from point a to point b the encoder keeps track of the number of flashes there probably is a 1000 or so perforations around the disc so even a very small fraction of a rotation is even monitored. So to repeat the same moment from home position 0 point the controller just runs the servo to the same point by using the encoder data stored. A little more to it than that such as it can also tell how fast it is moving and direction by the encoder. So there is where you get the extreme accuracy, even 1/1000 of the motor rotation is counted and the harmonic drive may be 50 to 100:1 ratio.
I was going to reply very similarly! I used to work at Toshiba, and they used many different types of robots but all were similar and used absolute encoders with servo motors. We used stepping motors on other machines but not the robots! I used to work mainly with the big Nachi robots! Miss that job!
This channel is great, always something actually new to learn! Other channels just cover the same old stuff I worked out as a kid (lift, basic electricity, basic powerplant etc).
industrial robots very rarely using stepper motors. servos are much more common... also industrial machines NEVER use open loop system. they rely heavily on position encoders...
position encoder is feedback device. it is mounted directly on motor shaft (in most cases) reading motor movement and feeding it back to driver. hence the term - closed loop gathered information can be used to verify motor movement, accuracy and repeatability, compensate for high load, overload detectoin, detection an compenastion of mechanical parts wear and many more...
No it isn't better. A lot of it is wrong but it doesn't matter you won't remember any of it anyway. What is reluctance? Why does Tesla use AC motors? What's the difference between stepper and induction? TL;dr
@@BariumCobaltNitrog3nhe's just trolling I do agree with you however, students need to learn the fundamentals and related equations to know properly what's going on. The original comment is just a shallow gripe about the education system
ratgreen the precision you can have with them is insane. imagine a SM with many more coil pairs and teeth that can do fractional stepping based on the coils that you engage.
The inventor of the stepper motor is genius. The person who decided they should be made from cheap sheet metal is genius. They made stepper motors before computers to get accurate positioning by remote control, also genius.
I think Oriental Motor has 5-phase steppers that do get more accurate positioning. You image, somebody delivers. I think it is patented, so they aren't too popular yet. But they are known for quieter operation and better accuracy, and higher prices.
You guys are just amazing. Every time I click on your videos, I just know I'm gonna learn something and that too in a simplest way possible. Thanks y'all. ❤
I invented this technology in 1974 while developing a blood analyzer. The technology was never patented since the company was a medical equipment developer and manufacturer. I taught the representatives of Superior Electric, the company that supplied the stepper motors, and the technology was published in training and repair manuals for the blood analyzer. I did encourage the company, my employer, to patent the micro stepping technology but the marketing department who was ask to review the commercial value said they could not find a market. Superior Electric was first at manufacturing micro stepping hardware based on my teaching them how it worked. I am presently working on an advanced driver technology that will improve efficiencies of operations and motor heating. Which I intend to patent. I am also working on motor improvements that will reduce the drive voltages both of which will open a new market to higher speed and higher power application of stepper motors. Larry Durkos
are those dc servos or hybrid s as in steppers with feedback loop? I know DCs are way more efficient and powerfull but seeing that even cnc machines use steppers makes me wonder why cant they just use brushless dcs with a quadrature encoder.
Google+ SUCKS BALLS - the worst forced social network wish i oul get one of those. I've been trying to get a dc motor with an passable res encoder and the built in reduction and no luck, i either find the motor with one or the other, but never the two at the same time :(
Some servomotors are closed loop stepper motors. Although AC motors are the most common, but older machines tend to use DC brush motors, not stepper motors.
thundercactus yeah, and those are expensive as fuck! If it's not for a very expensive machine, or if it is for some home project, better use a dc motor with an encoder and an arduino pro mini as the pid positional control.
That is not entirely true. Servo motor has a closed loop system to achieve precision, meaning it has an encoder on the motor itself and a driver that reads encoder information to achieve/correct positioning. Many motor types can be used as a servo motor. AC servos are most commonly used, not steppers.
Spot on mate AC servos are most common in automation and are completely different from stepper motors. Typically using resolvers or hyperface encoders to provide a closed loop feedback of the motor position.
Excelent video. But i thought that all the robotic arms motor was a servo motor, stepper motors are too heavy compared to a servomotor with the same torque. Anyway, very nice explanation and keep going =)
hi guys I am helping someone with a stepper motor though I am not into motors .. I would like to use a smaller stepper motor for an application but is it possible to deliver the same torque with gears? and how does the ratio matter of the bigger and smaller stepper motor relate to each other? does 2 times a diameter deliver a 2 times higher torque?
Aren't the hybrid's windings wrong? I mean, their magnetic fields seems to be backwards. If we follow the current direction through the coils, every instance where it says north it should be south and vice versa.
There is a channel dedicated to creating music using stepper motors mounted on a guitar to amplify the sound ans it's one of the most beautiful things i've ever seen
Servomotors refer to a closed loop system, not a specific type of motor. The most common servos are AC motors, with older machines using brushed dc motors. But stepper motors can be used as a closed loop servomotor.
I have not seen the robots (except toys) which use stepper motors it seems to me that a much better solution is a servo motor (ac gear encoder). It seems to me that this is due to heavy weight stepper motors.
hobby machines may use stepper motors, but older machines used dc brush servos and new machines use ac servos. There's really no excuse to not have closed loop feedback control in a machine that requires consistent precision.
Let's assume we're looking at only 1 of the 48 stator teeth. Call it tooth 'x'. Also, let's assume we're looking at only 1 of the 50 rotor teeth. Call it tooth 'y'. We know one of the following cases could occur: 1- 'y' is left-half aligned with tooth 'x' 2- 'y' is perfectly aligned with tooth 'x' 3- 'y' is right-half aligned with tooth 'x' 4- 'y' is unaligned with tooth 'x' or any other stator tooth Therefore, we have 4 possible scenarios for each rotor tooth. This means we have 50*4=200 different rotor tooth positions. We also know that rotating 1 revolution means rotating 360 degrees. Do the calculations: [360 degrees]/[200 positions] = 1.8 degrees/position
It is clear from the diagram. Each time the rotor has to move 1/4th of angular pitch to align with the new North pole. The special geometrical arrangement facilitates this.
Okay , I'm working with this robot arm and it started attacking me like it has gained a sentient state of existence .. It has made its intentions clear , What have I DONE??!! What have I created !!
Excellent basic introduction to how this motor functions - thank you for taking the time to make this video. It is frightening though, to think that China produces millions of these highly accurate motors for pennies.
Wish this video mentioned that a large part of the design in the hybrid stepper motor is there to reinforce the strength and accuracy of step position alignments and the underlying principal behind moving in steps is exactly the same as the simpler variable reluctance motor.
Great video. I wish you had better audience and make more of them as your work is extremely usefull to understanding basics of operation for people that cannot get this knowledge easily enough or in reasonable time.
Amazing. Your videos just send big doses of adrinaline in my blood and make feel as though am the one who created all that technology. Thanks a million for the knowledge
I use steppers with encoders on the ballscrews on my Cnc Mill conversion. I used 1150oz Superior Slo Syn steppers and Gecko drives, breakout board, wired in a speed configuration.. Been running Mill now since 2010 no issues. Its only faulted twice in that time, once because i forgot a table lock was on... other was during a 3 axis 1000IPM rapid so i cut rapids to 800ipm and its fine. Steppers still work in 2023. But id really like a modern servo spindle motor so i can Synchro/Tap etc.!!! Best wishes all!! keep building stuff! 😋🥲
Thank you for making such a great video! I understood the first motor though I didn't get how exactly the more common one works however I got some intuitive understanding of how they work.. thanks
Great video, explains it very well. But its only part of the story. All of that needs to be controlled by a computer. And you need some kind of a 'feed back' so that the computer knows where the rotor is at all times.
excellent videos.each video covers all important concepts of a particular machine. animation and explanations are pretty good. kindly upload more videos on special electrical machines
Some stand fans even have this motor, either the motor is connected to the oscilating mecanism, the blades (or the exposed shaft with a pin that secures the blades), or both.
Modern robots use 3-phase motors, like a modern electric car use. Its just magic, they use the Current Vs Voltage readings of each phase to compute the displacement. Magic.
Could you please elaborate more about why you are starting off , you have both pole on vertical coil of A and south poles on horizontal coil of A.Also why do those arrow point in that directions.Thank you and I love your videos but I am struggling with electromagnetism
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Is it possible to reduce the step size if we replace the rotor and stator having different no of teeth?
say 72 rotor teeth and 70 stator teeth will we get a step angle of 1.25 deg?
Make a better video then maybe??
Learn Engineering
createlyf ,,,yaa ,,it deepends on the type of application, but normally made with 1.8degree step size,,
The clarity of the explanation reflects the depth of your knowledge. Your graphics team has worked hard too. You deserve every penny you get. Well earned!
Videos like this saves me a ton of hours learning.. Keep the great job
Very smart people must make these. Such clear, simple and to the point explanations.
I have worked on many industrial robots at an automotive company, All used servo motors with encoders attached and harmonic drives. The harmonic drive is a very high ratio speed reducer and doesn't use gears so there is almost no play, The encoder is hooked directly to the motor shaft, it consist of a thin wheel with small perforations and a led on one side and light detection on the other. As the motor turns the light going through the perforations are read and counted. So when the robot goes from point a to point b the encoder keeps track of the number of flashes there probably is a 1000 or so perforations around the disc so even a very small fraction of a rotation is even monitored. So to repeat the same moment from home position 0 point the controller just runs the servo to the same point by using the encoder data stored. A little more to it than that such as it can also tell how fast it is moving and direction by the encoder. So there is where you get the extreme accuracy, even 1/1000 of the motor rotation is counted and the harmonic drive may be 50 to 100:1 ratio.
Does the encoder use gray coded binary, or is it just based on rotation but not exact position?
44 teeth just like a micrometer .
I was going to reply very similarly! I used to work at Toshiba, and they used many different types of robots but all were similar and used absolute encoders with servo motors. We used stepping motors on other machines but not the robots! I used to work mainly with the big Nachi robots! Miss that job!
As one who used steppers in my CNC, it is VERY interesting to see the design intent contained within.
This channel is great, always something actually new to learn!
Other channels just cover the same old stuff I worked out as a kid (lift, basic electricity, basic powerplant etc).
What are you doing step motor?
Lol
I never thought I'd find such a comment here 🤣
narrators voice was done using stepper motors. lol
Wah ha ha. You are right.
ha ha,,,u r right,,,,joe,,,
I feel like hes yelling at me! (lips quiver)
I can barely stand this style of narration. It’s just feel incredibly fake. Please remake this and just talk to us normally next time. Thanks.
@Evi1M4chine
O
theres a guy on youtube that makes music with these, but by the looks of it, smaller snd cheaper units. It’s awesome.
@@Eternal.Enigma In part, same XD
I have learn from these chanal simple understanding ........................
industrial robots very rarely using stepper motors. servos are much more common...
also industrial machines NEVER use open loop system. they rely heavily on position encoders...
@jozef svantner Can you explain what is a positional encoder?
position encoder is feedback device.
it is mounted directly on motor shaft (in most cases) reading motor movement and feeding it back to driver. hence the term - closed loop gathered information can be used to verify motor movement, accuracy and repeatability, compensate for high load, overload detectoin, detection an compenastion of mechanical parts wear and many more...
Billy Willy what is a resolver?
jozef svantner thank you for your reply. Can you shed some light on functionality of inductosyn?
totally i agree with your opinion, anyway, the explanation about stepping motor is awesome!
An amazingly explained video, you guys earn every penny that goes to your patreon.
extraordinary mental capability for whoever invented this motor . ..salute him
This is way better than going to class and sitting for an hour and 50 minutes listening to someone yap and draw crappy diagrams on a whiteboard.
Ifkr
No it isn't better. A lot of it is wrong but it doesn't matter you won't remember any of it anyway. What is reluctance? Why does Tesla use AC motors? What's the difference between stepper and induction? TL;dr
@@BariumCobaltNitrog3nYou mean the way you forgot sentence structure?
@@martinswiney2192 That didn't happen
@@BariumCobaltNitrog3nhe's just trolling
I do agree with you however, students need to learn the fundamentals and related equations to know properly what's going on.
The original comment is just a shallow gripe about the education system
The most clear explanation videos from what I've seen!
The same
3rd time i tried to understand this.. finally a video that explains it good..
No, I don't got it...
@@phorzer32 Probably, it's just not something that can be understood from the 1st time :-) At lest, as for me.
@@stkupr No, I'm just verry dumb
Great video. Whoever invented the stepper motor is a genius.
ratgreen
the precision you can have with them is insane. imagine a SM with many more coil pairs and teeth that can do fractional stepping based on the coils that you engage.
The inventor of the stepper motor is genius. The person who decided they should be made from cheap sheet metal is genius. They made stepper motors before computers to get accurate positioning by remote control, also genius.
I think Oriental Motor has 5-phase steppers that do get more accurate positioning. You image, somebody delivers. I think it is patented, so they aren't too popular yet. But they are known for quieter operation and better accuracy, and higher prices.
Dennis Fox Probably wasn't Al Gore.
@Evi1M4chine Yeah? What have you made genius?
The clearest explanation for a stepper motor I’ve ever seen.
Brilliantly explained and finally I understood how,what & why of Stepper motors and its applications.
thanks
Take a minute to appreciate the ingenuity behind this tech
Thank you for everything! At first I was skeptical of the slowness of your explanations. Now I appreciate that!
2 years ago I joined a company where we use this exact motor but I forgot I ever watched this video
First time i learned how a stepper motor works. Watched tons of milling videos too. Engineering is so amazing. Humans are so smart!
You guys are just amazing. Every time I click on your videos, I just know I'm gonna learn something and that too in a simplest way possible. Thanks y'all. ❤
👌
I invented this technology in 1974 while developing a blood analyzer. The technology was never patented since the company was a medical equipment developer and manufacturer. I taught the representatives of Superior Electric, the company that supplied the stepper motors, and the technology was published in training and repair manuals for the blood analyzer. I did encourage the company, my employer, to patent the micro stepping technology but the marketing department who was ask to review the commercial value said they could not find a market. Superior Electric was first at manufacturing micro stepping hardware based on my teaching them how it worked.
I am presently working on an advanced driver technology that will improve efficiencies of operations and motor heating. Which I intend to patent. I am also working on motor improvements that will reduce the drive voltages both of which will open a new market to higher speed and higher power application of stepper motors. Larry Durkos
PERFECT explanation as always. Thanks!
4 years and it's still the best video.
Very well explained, thanks.
Best explanation of stepper motor I have seen so far. Thank you.
To be accurate.. most robotic arms use servos not stepper.. nice explanation anyway.
are those dc servos or hybrid s as in steppers with feedback loop?
I know DCs are way more efficient and powerfull but seeing that even cnc machines use steppers makes me wonder why cant they just use brushless dcs with a quadrature encoder.
Laharl Krichevskoy this are plain dc motors with feedback loop.
Google+ SUCKS BALLS - the worst forced social network
wish i oul get one of those. I've been trying to get a dc motor with an passable res encoder and the built in reduction and no luck, i either find the motor with one or the other, but never the two at the same time :(
Some servomotors are closed loop stepper motors. Although AC motors are the most common, but older machines tend to use DC brush motors, not stepper motors.
thundercactus yeah, and those are expensive as fuck!
If it's not for a very expensive machine, or if it is for some home project, better use a dc motor with an encoder and an arduino pro mini as the pid positional control.
Excellently explained and thanks a million for NOT having any background RAP CRAP noise OR any other distracting sounds.
very nice. the theory was great, regardless of others comments. easy to grasp for non engeneer/teckie types.
2bikemike
Absolutely perfect animation and level of detail for an introductory video!
SO simple yet SO effective! Half stepping is crazy cool! Holy shit humans are amazing.
eyyy a fellow technology fan
Nature is amazing, we're just amazing at exploiting it's features :)
I misread the title and was like what is step motor? But I actually learned something so thank you.
Spaceyman brought me here.
I swear these animations teach us better than those teachers' hands.
make a video on servo motor. .
They just did.
65 idiot likes!
They are two in the same. One likes speed the other likes torque. Same class of motor though.
Nazim Ud Din okay
okay
That is not entirely true. Servo motor has a closed loop system to achieve precision, meaning it has an encoder on the motor itself and a driver that reads encoder information to achieve/correct positioning. Many motor types can be used as a servo motor. AC servos are most commonly used, not steppers.
Spot on mate AC servos are most common in automation and are completely different from stepper motors. Typically using resolvers or hyperface encoders to provide a closed loop feedback of the motor position.
Thank you So Much !
Theory was not that intresting watching your video & studying know give's ma good idea how it word's .
thank's again !
Thank you sir you are the one who given complete understanding of the hybrid stepper motor working principles
Excelent video. But i thought that all the robotic arms motor was a servo motor, stepper motors are too heavy compared to a servomotor with the same torque. Anyway, very nice explanation and keep going =)
Yeah great vid, but industrial robots and CNC machinery all use servos. The only ones that use steppers are low end hobbiest models.
Evan Bunke Exactly = )
hi guys I am helping someone with a stepper motor though I am not into motors .. I would like to use a smaller stepper motor for an application but is it possible to deliver the same torque with gears? and how does the ratio matter of the bigger and smaller stepper motor relate to each other? does 2 times a diameter deliver a 2 times higher torque?
2:04 "the rotor will come in between these two cases, or it will move 15 DEGgggREEeeeS"
nice explanation thoo..loved it
Great 🏆 You should make a video about Switched Reluctance Motor.
Thank you guys, that was the best explanation of how a stepper motor work. Great job !
Aren't the hybrid's windings wrong? I mean, their magnetic fields seems to be backwards. If we follow the current direction through the coils, every instance where it says north it should be south and vice versa.
EXACTLY
Who the heck envisioned this? Mind Blown 🤯
OK, well understood the step motor. But one more question: How do you rotate the 1.8 degree motor in the reverse direction?
reverse polarity
"Reverse the polarity" - the near-universal solution to every problem a Starship engineer will encounter.
There is a channel dedicated to creating music using stepper motors mounted on a guitar to amplify the sound ans it's one of the most beautiful things i've ever seen
But It seems the N S pole not obey right hand rule?
Good explainer video!
Are you sure that these robots used stepper motors? I thing they use servo motors.
Servomotors refer to a closed loop system, not a specific type of motor. The most common servos are AC motors, with older machines using brushed dc motors. But stepper motors can be used as a closed loop servomotor.
I have not seen the robots (except toys) which use stepper motors it seems to me that a much better solution is a servo motor (ac gear encoder). It seems to me that this is due to heavy weight stepper motors.
hobby machines may use stepper motors, but older machines used dc brush servos and new machines use ac servos. There's really no excuse to not have closed loop feedback control in a machine that requires consistent precision.
toys ..........................................?!
They only video that nailed it
can someone explain to me why the step angle is 1/4 of the angular pitch
h ????
Let's assume we're looking at only 1 of the 48 stator teeth. Call it tooth 'x'.
Also, let's assume we're looking at only 1 of the 50 rotor teeth. Call it tooth 'y'.
We know one of the following cases could occur:
1- 'y' is left-half aligned with tooth 'x'
2- 'y' is perfectly aligned with tooth 'x'
3- 'y' is right-half aligned with tooth 'x'
4- 'y' is unaligned with tooth 'x' or any other stator tooth
Therefore, we have 4 possible scenarios for each rotor tooth. This means we have 50*4=200 different rotor tooth positions. We also know that rotating 1 revolution means rotating 360 degrees.
Do the calculations:
[360 degrees]/[200 positions] = 1.8 degrees/position
It is clear from the diagram. Each time the rotor has to move 1/4th of angular pitch to align with the new North pole. The special geometrical arrangement facilitates this.
thanks n5roor this cleared up
thank you all for your replay
Podhigai
Very precise explanation , you guys are doing a great job.
Okay , I'm working with this robot arm and it started attacking me like it has gained a sentient state of existence .. It has made its intentions clear , What have I DONE??!! What have I created !!
Thanks Lesics team, you have an amazing art to teach typical things easily.
Imagine what would happen if this guy spoke to anyone in that voice face to face. SMACK!
Fantastic. Thank you very much! Folks, please support these people.
Thanks for your video it helps my channel grow and push me
make more, Good Job
Quite literally the worst voiceover ever. Why does every statement sound like an unsure question?
It almost sounds like a very advanced computer voice. Their videos have excellent animations but get annoying in the narration.
I like the narration. It makes me think that I am learning.
An android that loathes using contractions.
The up talking makes this very hard to listen to...
BEST TUTORIAL VIDEO I HAVE EVER SEEN ..THANKS
Looks hard to unerstand but that was hella easy!
Pretty interesting . I have heard of stepper motors but never knew what they were.
Excellent basic introduction to how this motor functions - thank you for taking the time to make this video.
It is frightening though, to think that China produces millions of these highly accurate motors for pennies.
Best visualization I've seen yet. THANKS for this.
Pls do video about servo motor
Your animation is awesome and it’s easy to learn
Keep it up.......
Même en anglais nous comprenons, imaginez que ces vidéos soient en Français, nous serons encore plus satisfait.
Wish this video mentioned that a large part of the design in the hybrid stepper motor is there to reinforce the strength and accuracy of step position alignments and the underlying principal behind moving in steps is exactly the same as the simpler variable reluctance motor.
A very good video, the working was well understandable and visible
Simple demonstration of a complicated operation. Great!!!!
This is tantamount to magic for most people
Great video. I wish you had better audience and make more of them as your work is extremely usefull to understanding basics of operation for people that cannot get this knowledge easily enough or in reasonable time.
Amazing. Your videos just send big doses of adrinaline in my blood and make feel as though am the one who created all that technology. Thanks a million for the knowledge
Thanks a lot for the video! Really helped me understand steppers
I use steppers with encoders on the ballscrews on my Cnc Mill conversion. I used 1150oz Superior Slo Syn steppers and Gecko drives, breakout board, wired in a speed configuration..
Been running Mill now since 2010 no issues. Its only faulted twice in that time, once because i forgot a table lock was on... other was during a 3 axis 1000IPM rapid so i cut rapids to 800ipm and its fine. Steppers still work in 2023. But id really like a modern servo spindle motor so i can Synchro/Tap etc.!!! Best wishes all!! keep building stuff! 😋🥲
thanks for the monitor animation and explanation.
thank for your well demonstration we willing to look forward for new updated video from you
nice explanation
@Lesics actually those industrial robots uses servo motor instead of stepper
Thank you for making such a great video!
I understood the first motor though I didn't get how exactly the more common one works however I got some intuitive understanding of how they work.. thanks
Great video, explains it very well. But its only part of the story. All of that needs to be controlled by a computer. And you need some kind of a 'feed back' so that the computer knows where the rotor is at all times.
I just got to say thanks, this helps a lot!
excellent videos.each video covers all important concepts of a particular machine. animation and explanations are pretty good.
kindly upload more videos on special electrical machines
Some stand fans even have this motor, either the motor is connected to the oscilating mecanism, the blades (or the exposed shaft with a pin that secures the blades), or both.
Good explanation of stepper motor
Very well done. Very helpful. I just supported you on Patreon.
Thank you for all your effort and hardwork.❤
This video helped me a lot to understand and visualize the topic, thanks!
Nice narration and video
Good and concise explanation. Thanks.
Please make a vedio on working of servo motor. Very nice work. Thankyou
Excellent Presentation
Modern robots use 3-phase motors, like a modern electric car use. Its just magic, they use the Current Vs Voltage readings of each phase to compute the displacement. Magic.
Thanks sir in advance !It is helpful for my project which requires intermittent motion.
Excellent demo and lecture !
Best explanation of the technique.
Шикарное объяснение. Спасибо!
Thanks for clearing my concepts
Thank you so much for your clear explanation sir
Amazingly educative video. Thank you.
Very nice explanation
Could you please elaborate more about why you are starting off , you have both pole on vertical coil of A and south poles on horizontal coil of A.Also why do those arrow point in that directions.Thank you and I love your videos but I am struggling with electromagnetism