How I gave my lathe a "nut" button, and why I'll never look back
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- Опубліковано 29 вер 2024
- Threading to a shoulder has never been easier with the nut button. Single-handedly reducing the number of code browns by an order of magnitude.
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Everyone go and subscribe to Jack, his side of the story is coming soon. I'll warn you though, he's literally a wizard.
www.youtube.com/@jackfromscratch
Just saw his profile photo and immediately subscribed, what a lad.
Should I meddle in his affairs? 🤔
i just order a similar servo except the 750watt nema34 version to run with clough's leadscrew project but was wondering does the driver require a separate dc power supply or just 220v ?
hope its not as screamy other wise i would have to try a nema24 stepper or order a nema34.
Only one video...from six months ago. Show me the code!
Working on it! Life has been hectic so I'm a bit behind schedule - I'll have it out this week!
making jelly in 4 different colors for 2 seconds of a video is crazy.
worth it
totally worked
When talking something related to video it is sinful to not provide the timestamp
@@rameezsheikh7576 or you could watch the video to be in on the same funny hahas, but also 4:50
That's gelatin for the Americans.
I feel like you need a PULL OUT function to go with NUT mode. For those times you want the thread to lift off at the end rather than cut a channel/groove
And a button to use just the tip?
Just make the cheap lathe into an expensive cnc lathe :)
if you can tell it to make multiple passes, call that SUPER NUT
And perhaps a SPLOOGE button to have the coolant running while cutting is taking place.
@@NGeese That's called the bukkake button. AVE covered this on his channel while programming some CNC mill stuff.
Ok, now I'm starting to get really suspicious. Teaching a lathe to think is exactly the kind of thing an engineer would do. Especially without stopping to think if you should teach a lathe to think.
Someone looked at the "This machines does not have a brain, use your own" sign and thought "But what if it did?"
@@MazeFrame I for one welcome our robot overlords
Also teaching the lathe how to nut. He's making his lathe more and more human every day
With a bit of mental calculation, an Engineer would be thinking, that's a waste of time, and therefore, he's not really an engineer
@@junkname9983 Haha quit lying. Everyone knows a true engineer will gladly spend 3 weeks designing a process/tool to save themselves 15 minutes of work every 2 months.
I've been exactly where you are. What really hurts is knowing a primitive Fanuc 2000C control from 1974 can cut perfect threads at 3000 RPM...
Downright geniuses the old geezers were!
Beat me to it.
hypnotic watching a cnc cut a tapered square thread at full tilt...
fecking hilarious watching the resident shop "fool" open the door too early and get soaked with flood coolant... on the first item of the day... "no change of clothes for you!"
4:05 "things were progressing at the speed of time"!! You make great word salad😂
"overwhelmingly undertensioned" and "emPloying the purportedly perplexing power of the floating point " were decidedly delicious!
Inheritance Machining and Not An Engineer have made the transition from This Old Tony a much easier pill to swallow.
Why have you had to transition from this old Tony?
@@bogdandrozdov6669 Tony has pretty much left UA-cam
He justed posted a month ago... @@AndySomogyi
@@AndySomogyi Not completely left, but he seldom posts anymore. I get the point though, and agree that these two have helped fill a void. I miss CaLem too.
@@bogdandrozdov6669 The transition of his upload schedule. Used to be multiple uploads a month to now a few a year. These channels definitely fill that void.
Hello google, How would I best express my admiration for a UA-camrs ability to combine modern poetry with metal machining and programming?
The upcoming "Hype" feature might be the ticket.
pretend you are my father and are teaching me all I must know about the praising-clever-creators industry before I inherit the family business
i was just about to go to sleep when this was uploaded. you are single handedly ruining my sleep schedule.
im really sorry, but it definitely adds to the immersion
@@NoEngineerHerethats fair
Legitimately same here😅
Right there with you
I just woke up and saw it, so my sleep schedule is fine 😂
Asking for a friend......
How would one go about getting a copy of that "This old Tony" smut fiction?
This may violate our content policy
All this threading and nutting, man i wish i was an engineer.
0:42 HE SAID THE THING
4:44
He did it again
i'm assuming your lathe will shout "NUT" in a robotic voice whenever you press the NUT button. now that your lathe has an MPU, it can say anything. you could even connect it to the ChatGPT API and give your lathe a personality and have conversations with it based on what its currently doing.
Machining and microwaves is way ahead of me
TBH, what's really needed is a single voice clip:
"Are you sure about that? Make sure to check your settings before proceeding."
> give your lathe a personality
That's a really dangerous idea. It ends with the Sirius Cybernetics Corp., Genuine People Personality, and Eddie the Shipboard Computer.
"All the lathes in this shop have a sunny and cheerful disposition..."
6:45 Finally, someone who appreciates TOT as much as I do 😌
That whine might be related to PWM of the servo driver... Which means it's likely unfixable. You'd want different driver for the servo. Or if it came from supplier - new servo+driver altogether... Alternatively - ask manufacturer.
My sense as well. If you load up the shaft with your finger and it doesn't go away or change then this is almost certainly the case.
You can change the PWM frequency in software in Arduino(I think the drivers typically just bounce the microcontroller pwm along). It messes with your delay timers and some other stuff but it's actually a simple fix - I had this exact problem, changed the PWM frequency to like 7812 Hz (low pleasant hum) or something and it was gone completely.
Just add to setup:
TCCR0B = TCCR0B & B11111000 | B00000010;
and that should fix it (and maybe break everything else)
B00000001 will set the frequency to 62kHz if 7kHz is still annoying, but the microcontroller or motor might not be able to differentiate the pulses.
@@MrTheomossop interesting. What kind of motor/drive is this. I've never used servos outside of the big industrial mfg (AB, Fanuc, etc) on similar tier controllers.
@@MrTheomossop This PWM frequency is generated by AC Servo motor controller in hardware. Manufacturer definitely can change the frequency, but we cannot do it...
@@BarsMonster Many industrial servo drives and VFDs let you choose between a few different switching frequencies with a parameter.
I feel like the lathe needs a "DEEZ" function next.
Not sure what it would do, but you're the not-an-engineer, so you figure it out.
the warning at 11:08 has the wrong timestamp
Came here to also mention this
You're going to accidentally make an entire CNC lathe, at this rate. I'm not against the idea, but you ought to mentally prepare yourself.
See why change gears have their use? They don't need any code to work, and at the same time they're silent at rest
thats nuts
Bravo! 🎉
this project is so hard that you have used the forbidden technique: "project management "🤢
did you watch Clough42's series?
it might be helpful
The servo drive is likely designed to work at a 8khz switching frequency. It uses DC to pretend like it has 3phase AC. in doing this it switches some solid state switching devices, like mosfets or IGBTs, at a specific clock frequency. It modulates how many clock cycles it leaves the full DC voltage on to approximate the power of a sine wave. Lower end AC servo drive tend to run a slower speeds, which usually end up in the audible range, you would want something at 20kHz or higher, maybe even 32kHz clock speed. The better ones even let you choose which switching frequency to use.
Bruh, do you imagine how high of an inductance the motor would need if you were switching it at 8kHz?
@@allenomak Tell me you have no clue how servo drives work without telling me you have no clue how servo drives work
Right from the start, with the fake mic check on the torch nozzle (and perfectly timed sound of touching the real mic), I knew I was in the right place on my own lead screw.
And it's not even November
No-notanengineer-november
What no dancer, Budget constraints?
A sad reality we must all face sometimes. I’m sure @notanengineer would accept, since you’re offering, a video short from your own camera 😅
@@ryansmith209 Trust me you dont wantt to see me dancing
The whine you hear is the sweet sound of the pwm of the servo inverter output stage. And totally normal! Creating the sinewaves to Drive the servo by swiching with 8khz the (i assume) three Phases to the Motor on and of for the right amount of time to let it Look like a proper sinewave. Doing that on the three phases correctly, with the right Shift in between the phases, you can do awsome things with Servos. Even let them sing jingle bells. I did at least….
Oh where was I? Ah yes, two options:
1) may be you can have a look to the servo inverter manual if the frequency of the pwm can be changed. If you‘re lucky you can change it to 16khz. Than it should be gone. That will come with the cost of more powerlosses / more heat of the inverter. Bit since you do no back and fourth +/-3000 rpm 10 times a second, heat wont be an issue. Lowering the pwm Frequency to i.e. 4khz might be a bit more pleasing than 8 as well. It comes with the downside of precision loss. But that shouldnt be a problem on your application either. Be aware, you might have to tune the pid closed loop controller again after you were hopefully able to change the pwm.
2) These inverters usually have an digital„enable“ input. Set it to „0V“ if you dont need the motor. The pwm will be switched off. But the inverter still has power waiting for you to set enable again to apply torque, speed an squeeking from hell. So no pwm no cry. That works if, I assume, the leadscrew sees no load and the carriage stays in place if theres no torqe of the motor on the leadscrew or even no motor at all.
If so, you can have lathe motor off -> servo off or lets call it „standby“. Or only on, if you enable it from your fancy dancy microcontroller (nice thingy btw). Or just during movement. The enable/ disable is usually quite fast may be just a few milliseconds. But since the Delay is consistent, you can take it into account in your code. And that Method saves power.
Sry for the wall of text :D
Hope that helps.
Thanks for your vids man!
I am skipping my political science class to watch this, and my justification that I am studying to be a real engineer
I love how far you'll go for a gag. That Jello bit is hilarious.
People will be studying his content for 1000 years in order to extract the fundamental truths of the universe.
8 kHz is probaly the PWM-Frequenzy your Driver (i.e. Frequency Inverter) uses and is causing the Stator to vibrate. 4, 8, 12 and 16 kHz are quite common, with the lower frequencies being more efficient but of course definitively in the audible spectrum. Check if you driver can operate at a higher PWM-Frequency (should be an option in the parametrisation of the drive) or get one that can. This will increase overall losses in the system, but that doesn´t seem to be of concern.
1% of the way to get a full CNC...
0:35 - how could you skip this opportunity? nUt an engineer
Your assessment of life just being one continual project, is exactly my experience. 🍻
I suspect the 8kHz is just the inverters motor phase PWM modulation frequency. I notice some EVs have a similar annoying wine at low speed.
I give this lathe mod an 8/10. I would give it full marks 5/7 with rice, if when you pressed the button it also sounded one of those office nut buttons that says NUUUUuut
You dropped the Bresenham algorithm and replaced it with floating point calcs??
Yoo do know Bresenham has no cumulative error but floating point does?
That was a big step backwards. I do motion control products for a living.
Safety Troll tip:
Double check the torch is not lit before you start recording! 😵💫 🥴 😜
I'm only watching your videos on repeat to convince myself that my projects are going smoothly.
ANOTHER high end microphone. This guy is a baller.
Duuuudddeeeeee!! You've outdone yourself on this one. Absolutely phenomenal project and video. Mind blown!
Nut An Engineer
🔘🫲
I too have learned to travel at the speed of time.
I'm just here for the This Old Tony AI smut.
me too. Those hands are such a turn on. Alas, he doesn't make as many videos as we'd like, and so we have to entertain ourselves some other way
Spaghettitronics bwahahahaa
So... is that TOT smut published anywhere?
Not the hero we deserve, the hero we need right now.
2:28 you are not my friend. Oh i need to make x but to make x i need to make y but i need to make z to upgrade machine to make y but to make z i need to make q and to make q i need p
My exact words when I saw this "OH NEW VIDEO"
If you want to try getting rid of the whine, i think it's parameter P0A-09.
"Maximum position pulse frequency | 100~4000 | kHz". Near the top of page 41 of the manual (if i have the correct manual..)
It should be called switching frequency or foundamental frequency, but I don't think it's correctly translated..
no. that defines the input pulse frequency; it has nothing to do with the whine
@@ikbendusan You're probably right.
In that case i don't see any parameter specifically for switching frequency.
He might have some luck contacting the manufacturer, since it might be an implied part of one of the other parameters, but otherwise I think he should just get a better drive.
@@Gaatash it's a chinese manufacturer; he's SOL if he needs help from them directly lol
2:22 brooooo, I didn't expect a therapy session 😭
pressed pause at purportedly perplexing power phrase to give my thumbs up 👍
Super cool video... and im just doing a video on a project using Clearpath servo's, where I would like to show how easy they are compared to other servo brands.. could include a short piece of your video to show the PID love :)
Meh acceleration is overrated, you're not going to be threading at 2000rpm with a leadscrew driven carriage anyways. Some closed loop stepper drivers and servo controllers have smooth ramp up options to take the edge off. I've been planning on adding scurve to my ELS but haven't found the need for it yet.
I did a bit of threading at 2000rpm when I still had the change gears on. The surface finish was well worth the pucker factor (threading away from the chuck, of course).
The servo was doing a great job of easing into things, just at the cost of furthering my descent into madness.
@@NoEngineerHere the half nuts will quickly wear out, at least the crappy bench lathe I have won't last long if I push it that hard
the servo parameter you looking for might be called “deadband” or something like that. expressing in some unit (mm, tens or hundreds or microns or maybe encoder ticks) the physical rotation amount being disregarded by the PID loop. “close enough” parameter, basically. that should be set to at least the difference between the steps of your encoder and the ones of your servo. other option is too tune a more accurate PID loop. but that can be a nightmare, specifically if your only interface are the buttons and menus on the servo controller.
sometimes there is also a higher level parameter called “load inertia” or so that will change a whole range of other parameters according to a non-user-accessible lookup table.
i hate it when my rubix cube turns to jelly
You deff are not the only one feeling life that way for sure, I for one (being nirodivergent), love this way of living now tho!
I love your videos , you’re like a personable and Australian version of me 😂
What size stepper / servo did you use ? I have a similar sized lathe (300x1000) and starting an electronic lead screw project myself .
One option I’ve toyed with is I have a 2.5 kW BLDC motor and keep meaning to fit it to drive the spindle . I wonder if I at least control the acceleration of the spindle with it ???
BTW, I’m a physicist / electrical engineer by day and amateur car restorer / fabricator by night .
What is the specific make and model of the servo you got? I use servos all the time at work so I could take a look at the manual and see if any tuning parameters pop out at me to look at changing.
8khz is an odd frequency for jitter noise or mechanical imbalance. It is possible that the noise is unfixable, and simply part of the low cost design of the unit. Since it is a low cost part, the drive may be using a carrier frequency control method with an 8khz carrier wave. Uncommon on servos, and that is usually more like VFDs. It is possible though that the servo is functioning like that. The carrier frequency when using VFDs is usually audible like you have in your system, and in servos you usually hear no such sound.
It's a lichuan a5 driver, cheap and cheerful of course.
Strangely the noise seems to abate if I add damping to the motor shaft, just by pinching it between a couple of fingers. That's what led me to the jitter conclusion, but you're probably right!
@@NoEngineerHere Hmm if it sounds better when you add damping, then it might be that the tuning of the torque loop isn't great (specifically the torque loop proportional gain, which can cause a high-pitched whining that sounds exactly like this). Unfortunately looking at the manual it doesn't seem like they give the user access to any of the torque loop gains...
But yeah IMO it's probably the PWM noise causing the coils to vibrate within the stator. I work in a servomotor test lab and last year I spent several days trying to track down an identical-sounding whine and that's what it ended up being.
The position jitter typically has a much lower frequency based on the bandwidth the position loop is tuned to (which is rarely going to be above like 100Hz) and sounds a lot rattlier, and you probably would have noticed a difference when you were messing with the position loop gains. Also if it was tuned stiff enough to be audibly ringing, it'd likely go crazy unstable when you move the shaft
So maybe add a bit of rubber of felt or something to put a small amount of drag on the shaft?
You know, you're pretty close to making a whole CNC lathe. Why not go full CNC?
Awesome. You crack me up. The odd mic every time. Lmao.
LETS NUT
On a serious note perhaps a drive for the spindle motor? Nice gentle start and stop with the added bonus of infinitely variable speed in ranges. Forward and reverse availability if you do a CNC conversion?
Also I have used a machine that used to disengage the lead and/or feed screw via a mechanical trigger. If you are not going CNC and have trouble with the half nut?
Definitely planning a servo driven spindle upgrade. You've hit the nail on the head - acceleration would be so much easier with coordinated motion.
I do want to keep it as a manual machine, CNC lathes are a whole other level of shit-your-pants territory
@@NoEngineerHere Indeed, perhaps a simplified approach a single direction feed per cut. Think cuts tapers but wont do a chess piece? Don't even need to change lead screws then. But maybe I need to give the RedBull a break...
Dude, 100% 'Project Inception' here in the Fat Cave, too...
Plus, if you complete one, two more jump on the bottom of the 'to-do' list.
And I am an engineer. I was so good at it I became a journalist.
Love your work.
Aw but the circles of hell and code related insanity trying to teach transistors to behave is the fun bit.
Mind you I am an engineer... a software engineer. We're engineers too 😏
Software+Optical encoder? Spinning wheel with a tab like for measuring RPM. Software reads from lathe and adjusts, instead of stepper driving lathe load directly
"it's projects, all the way down" - and most of them are 80% completed...
It seems like my whole life is a fever dream today, startes with overly vivid dreams before waking and now most of the youtube videos on my feed today being weirder than usual.
All of this effort... you could have bought a yaskawa mp3300iec motion controller, maple systems hmi, ac servos and had a badass machine. You probably would have exceeded the 30 day trial for motionworks iec but could have installed it on another pc.
1970 metal shop High School, everything was manual, cutting threads😬
Why not use glass scale from a DRO. They make DRO's accurate.
Haha, great video!
The whining sound is the electronics, as you sure found out. I've yet to encounter a mechanical part that has such high frequencies. Since a servo motor needs to stabilize the position, it always has to apply some torque=current=annoying noise. You can get rid of this, if the pwm frequency of the drive can be altered. * You already found out, that atm it's running at 8 kHz, which is very typical. However, many drives do 32 kHz and this is beyond my hearing ^^...
For the ac servo you might try the notch filter at 8khz. Also soft switching will reduced audible noise. Could also use 10 or 15 khz switching frequency so it’s not audible
Does the software allow him to check the fit of the thread by jogging away while in NUT/Sync mode?
You are two stepper motors, a computer and cnc controller from having a full cnc lathe. Maybe you can look into it
The whining noise usually comes from the pwm frequency used to drive the motor. The same happens if you try to drive led strips for example. If it is the case you need a higher pwm frequency, which might require a faster MCU. For that kind of project I like to use a cortex m4 based board, they have an "integrated DSP" that can manage fixed point floats pretty well, and lets you do field oriented control (FOC).
Possible acceleration solution. Why not add an extra fixed amount of distance.
Rate of acceleration would be (target_velocity^2)/(2*lead_in_distance)
Increasing the servo pulse rate over that distance based on 2.5mm of travel and the number of pulses per rotation.
Wait a damn minute... You're just StyroPyro but with a beard! Damn, had me fooled there. Guys, don't fall for him he's not an engineer.
I always use auto-tuning in servo, then lower the "rigidity" to lower the noise.
Xinje servo has a "Rigidity level" parameter.
Mitsubishi servo has an "Auto tuning response" parameter.
Delta servo has a "Response level" parameter.
HCFA servo has a "Stiffness grade setting" parameter.
That is all the brands I used.
And here I just turn the threading tool upside down to avoid the terror of stopping before it slams into the chuck! (Everything else about manually threading is still nerve-wracking though.)
The 8 kHz whine on your servo is coming not from the tuning (your servo loop can't respond at 8 kHz) but from the carrier wave of the IGBTs magnetically flexing the motor windings while generating the low-frequency sinusoidal AC from the DC bus. 8 kHz is a common carrier frequency in cheap servo amps, better ones have better lowpass filters to remove the carrier frequency, or to allow you to adjust it up to 16 or 24 kHz, generating more heat but pushing the primary up into ultrasonic territory outside the human hearing range (harmonics are still infuriating), or to adjust it down to a less performant but also less nails-on-chalkboard tone at 4-6 kHz. If your amp doesn't allow adjusting the carrier frequency, sometimes a few wraps of the UVW lines on a big toroidal choke can reduce it a little, but it's never going to go away. The easiest improvement is add a "servo off" idle timeout to your code to disable the amp when the spindle is stopped or when you don't move the carriage for 60s.
I'll betcha the 8 kilohertz whine is the switching frequency of the motor driver. Cheap drivers run at audible frequencies sometimes.
don't get down on yourself, Hardinge tried to replace the threading gearbox on the HLV toolroom lathe with similar ideas. never was able to get sync between screw and spindle right
The whine from the stepper is possibly from the PWM frequency used to drive the mosfets running the stepper coils. DRV8825 stepper drivers that were used commonly in 3D printers way back when had an annoying whine when idling for that reason. So, good news, it's not your fault you can't figure out how to fix it. Bad news? You probably can't fix it. It's baked into the drives.
FYI on your servo issue:
Usually, 'velocity proportional gain' has the biggest effect on that overshooting/hunting for position issue.
HAAS CNC mills have that axis whine too. Usually means (so I’m told by maintenance) that it’s a symptom of the power amplifier beginning to fail.
Regarding the 8kHz whine... I work in a test lab at a company that makes servomotors, and this noise is an issue we run into sometimes. Best case, changing the tuning can fix it. Worst case, you're stuck with it.
Last year I spent a solid 3 days trying to track down this exact same type of whining on a particular motor, also with no success. Besides the 9th circle of hell, the other most likely cause is PWM noise coming from the drive causing the coils to vibrate slightly within the motor, as some other comments have pointed out. And the unfortunate thing is that this can't be fixed unless you can change the drive's PWM frequency, which is usually not a feature that users can access.
But there are a few other potential causes which can be fixed by tuning, though it sounds like you've probably tried changing the parameters enough to where it would have been fixed.
If it makes this noise as soon as the motor is enabled while the drive is in current mode, then it's the PWM noise from the drive and you're screwed.
But, if it only makes the noise in velocity and position noise, then tuning might work. It's probably not the position dithering (as you discovered); that's caused by the position gains being too high and usually has a lower frequency and a much rattlier sound, and also tends to go unstable and run away pretty easily.
The other possible tuning fix would be to dial down the proportional gain in the current loop. If that gain is too high it typically sounds like this kind of high pitched whine.
But yeah... I share your pain. Like you, my background is more with mechanical stuff, so this electromagnetic and control theory crap is still confusing even after being around it for years. Basically it's all black magic that nobody understands
Your rubix cube bit made me realize I was not subscribed because I shared it with my engineer friend who entertains my Caractacus Potts fever dreams. So I figured I'd like the video as well I guess. And I subscribed. It was particularly disheartening when I realized that I have been viewing your videos for over a year and hadn't done so. So I guess I'm apologizing. But I'm not. Because I am a random stranger on the internet.
As an engineer, I just had to speak up after seeing PID control mentioned. Even if it was only in jest, the simple possibility of someone thinking PID is a valid or useful way to achieve closed loop control, absolutely terrified me.
PID is not something that should *ever* be used for anything, other than scaring engineering students into actually learning the maths required for proper control systems.
On a related note, the 8kHz noise might be coming from something that's pretending to be a VFD (or whatever is feeding AC to the motor). Most product designers/managers will do anything to avoid generating a clean sine wave; including substituting the end user for any and all harmonic suppression/lowpass filters and just bit banging (which is what it feels like, although it's not technically the correct term for the variety of pulse width/density modulation schemes that are used by The Chinese™ to produce fake copies of authentic sine waves.) current straight into a magnetostrictive device. Sometimes they even spinkle in some piezoelectric capacitors for the added buzz...
As for what you can do about it, if *The* *Issue* is in fact the latter and not an oscillating control loop: You can either filter the input to the motor so that it only sees a nice and clean sinewave, free from harmonics, or you can use a much higher pulse frequency to simply push most of the noise above 40kHz or so (which would still cause hearing loss, if it is loud enough, and might be even more dangerous since you can't even hear how loud it really is. This might also not even work, as the physical structure of the motor might be resonating at 8kHz, so you might need to go to even higher frequencies...).
A PID is a pain to wrangle, I deal with them quite a bit in the physics sim games I play (yes I like engineering so much it's my idea of fun)
It's crazy how such a tiny value change in one of the variables can turn a precision mechanism into a adrenaline fueled ADHD hamster or turn your drone into a bucking bronco, you basically have to graph what it's trying to do, what it's doing and what the target is so you can know and track your tune.
Hey! The 8 kHz tone is created by sub-harmonic oscillations in the AC-servo H-bridge driver and is purley an artefact of the current mode switching technique implemented by the driver chip. Message me if you want some help with that!
On our CNC router the servos do have curve settings and modes specifically to reduce “hunting”. I’m not really sure exactly what they are 😅 something about gain, integrals, and derivatives, torque offsets. I’m also thinking maybe you could add a damper or servo motor gear box so that it’s not “directly” influenced by your set up.
When the techs set up our machine they emphasized how grounding is very important
2:17 wait… it isn’t? So, you mean it is not normal that I locked (or, more accurately, blocked) myself out of my home shop with all the stuff I SWEAR I NEEDED to finish a project to finish another project to finish still other project, in order to finish the original one so I could finally remove all the clutter in front of it? It’s been almost a year… but it’s ok, I’m moving to a new house, so I guess I’ll just move all the stuff that I dont have a place for in my current shop to the new one. Hm. I might need to buy some more stuff.
Cheers, from a fellow non-engineer.
The annoying whine from the servo is coil whine probably just it holding position. This is a good thing. What you want to change is the motor pulse modulation frequency. Usually this is fixed by upping the modulation frequency above 20KHz which puts it outside of our audible listening range.
Somehow my music playlist started "Murph" from the Interstellar soundtrack as I was starting this video and having that as the background soundtrack was wild. I made it halfway through before realizing the soundtrack was not from the vid lol
When I program PLC's to control servos, I usually use a basic style logic of IF(Curr_Position == Setpoint_Position) for 2 or 3 seconds I remove the enable bit of the inverter, cutting the power to the motor. This makes it run cooler and stops the noise coming from the positioning algorithm, but has a side effect: If you need it to react instantly to a run command, you will need to predict that the command will happen next and give the inverter the enable signal back before your run command, otherwise the inverter will need to "wake up" and energize the servo for a few milliseconds before the servo actually starts spinning.
Maybe you can follow the following logic:
- If you have reached the desired position, remove the enable bit instead of maintaining it on with the same setpoint;
- If you press the N U T button, set the enable bit to ON but don't move the drive yet;
- If the sync position has been reached and the drive is energized for more than 100ms or so, start the process.
You might as well have said that in Klingon... I just don't know what you are talking about.
I think I'll stick with this old Tony. His explanations make sense.
I’m trying to get an obscure display to work with a stupid electronics tamagotchi-inspired project. I needed to get a logic analyzer to debug what’s going wrong.
The software for it runs poorly on my computer. It works, but it’s annoying to run.
Now I’m working on a web app so anyone with the logic analyzer can just plug it in and visit a webpage to start capturing data. I have the basic data capture working with a simple webusb “driver”, and now I need to get the display of the data working how I want. In that process I decided it was a good idea to render the data with webGL which I conveniently know next to nothing about.
Oh I also need to somehow implement basic SPI protocol decoding so it’s not totally useless and I don’t really even know much about how it works.
So anyway yeah I can relate to the feeling of having all my time consumed by side projects that were born out of minor inconveniences. I expect to finish my toy project once we have industrial scale nuclear fusion powering the planet.
@noengineerhere, RE: Motor whine - The Magneto X 3d printer has high precision motors like your steppers. Their solution was a hardwired kill-switch to enable and disable them. The whine is THAT bad.
Need another similar button marked "Bust a Nut" for the times someone tells you a good joke, but you're too busy to laugh.
After going through the same process a couple of years ago...
These are some of my learnings. Maybe some strike a chord
Use the Servo Drive
Spindle pulse train directly to Servo drive
Use the Servo drives internal electronic gear ratio (does it have RS485 or some other coms protocol available?)
Switch the pulse source between the spindle and controller for synced / unsynced rapids.
Feed two hardware counters on your main controller with the Servos AB pulse.
If your main controller has another two Hardware Counters then feed the spindle encoder into that but it's not as important as the Servo Encoder AB pulse.
Feed your main controller just the spindle encoder Z pulse to be used for spindle sync.
This should help free up a lot of processing on your main controller.