Awesome man! Lots of research and engineering. May i suggest one thing? Maybe you did it already but just in case... Optimizing the slicing layer by layer. There is tons of things at each layer you can set differently. Use modifier and tune each layer individually :) That is where you will gain the max time i think once you have reached the max from the hardware
@@Vez3DJan and You as well quite often write acceleration in several K of mm/s^2, so basically kilo-millimeters. Why do a lot of people do such a thing instead of just converting to m/s^2. Writing 500k mm/s^2 is basically (1000/1000)*X. Question is - why?
Yeah i know thats a thing. But I also got a regular job and social life :D maybe ill invest the time and analyse the motion vectors of each layer and apply a filter on top. Setting parameters layer by layer is just a pain...
With that massive delta between just the pulley and the weighted pulley, I'd love to see a few of these motors linked together shaft-to-shaft to see how high acceleration you can get with that. Ideally, 2x motors at 4a each makes an 8a motor, it would be very interesting to see if the motors working together would increase overall acceleration or just torque. If just torque, it looks like that would make the larger pulleys work better to possibly achieve higher acceleration through the gear ratios at play.
Hey super nice video series! Just had a weird shower thought kinda idea: could you make the extruder/hot end move as well? ofc not as fast as the build plate, but maybe a solid amount of movement opposite to the buildplate could increase the effectvive acceleration you can achieve.
so many commenters thinking they know better after watching a few minutes of video, not considering the hours and hours of development and work put into this setup.
Well yes but communication is also key when optimising something. Especially if you work on something for a very long time you can get locked in on a solution and fail to see a more optimal solution that may be apparent to someone who has not spent much time on it. Don't think that's the case for most people in this comment section though i might very well be wrong, however allowing communication whilst it may lead to a lot of terrible ideas might actually lead to something good. Just in general. Communication is essential. Speaking from experience.
Neodymium magnets are very sensitive to temperature. A motor with magnets on the stator, where all the heat of windings accumulates would most likely be more sensitive to heat than any other motor. Cooling the motor housing/windings will make most likely a noticeable difference. Its the same reason that speakers use much less often Neodymium magnets then regular ceramic magnets.
During your simulated weight tests I noticed that the steppers at that speed are actually flexing the mounting brackets causing the stepper to tilt downwards at the shaft end. This MIGHT be where some of your inconsistencies are coming from, as that slight movement would put extra tension on the lines and cause an artificial increase in weight which changes based on the angle of the stepper. Maybe redesign the mounting to include a clamp that holds the steppers down at the back as well?
Such a cool project! Really looking forward to seeing your next tests! More tension on strings or a stiffer material maybe to prevent the string from "flopping" around?
wuld it be better to tension the cable indirectly by removing the tension springs in line with the cable and instead use a pully which can be moved outward to tension, like a belt tension mechanism with a thumb screw?
@@sammiller5509the springs are there because the lines that connect the motors diagonally, have to be able to lengthen when there is movement in the other axis.
Two quick questions: 1. Could the drop in performance at certain accelerations be related to harmonics? It seems like a significant amount of energy might be transferring into the cable, judging by the noise. Perhaps a solution could be to add a sub-plate and mount the motors closer to the build plate. 2. Have you considered biasing the motor orientation along the length of the boat? This might allow for greater acceleration on the longer travels, making the power use more efficient.
Looks very interesting. I had a thought which may or may not make sense. Have you considered instead of syncing motors using 2 motors with a constant rate spring and maybe linear motors.
I think the slack comes from slipping of the loop on your cable, since missed steps would move the stopping point of the build plate. A second possibility is the cable slipping on the pulley and moving slack/tension from behind the pulley to the platform side. The issue with the larger pullies comes from the rotating mass of the heavy weight so far from the center. This issue will be resolved by lowering the weight of the pulley. The more mass the pulley has the more energy is used to change direction.
@@Roetz40 long heated nozzle pivoting to reduce moment , perhaps? Or just move the nozzle for shortest moves (infill chimney etc. ) . Missing out on the possible gain from relative motion seems wasteful
Hahaha the crazy part even though the actual benchy wasn't printed i could visualize what part was being printer just based on the movement of the hardware, iv been watching way too many benchy being printed :)
Why did you say that only open loop steppers are allowed? I thought it only said "The machine must be powered by stepper motors". So maybe closed loop to be able to push closer to the limit.
@@Roetz40We need a new speedboat competition. The rules of annex one are stifling innovation, not promoting it. Servos are no longer something that only companies and wealthy hobbyists have access to. They totally make sense to put on a 3D printer now. I can make a servo out of an RC hobby BLDC motor and a FOC driver that costs less than high end NEMA17 steppers. Also my personal peeve, is the focus it puts on *_one_* benchy. I asked recently on their discord server if it is OK to print, for example 10 benchies in 20 minutes, and call them 2 minute benchies. They said no. It must be a single benchy. There is no way to cool that much plastic in that amount of time. It is a material limit. Physics. You will only ever make poops at a sub-3min pace and they would rather see one pile of poop at 2 minute pace, than 10 actual boats at 2 minute pace. I'm not about to invest that time in making poops. BTW i made it clear that I meant one toolhead, one nozzle; not 20x nozzles printing parallel like you did before. Still NO. this speedboat thing has run its course and Annex are not willing to evolve it to the next level. I see no reason we should maintain interest in internet credits minted in 2016.
Why not use dual small high speed motors like you were using on each corner connected by a pulley drive? That way you can have low inertia and double your torque. I'm not according for losses. While you're at it you might as well make water cooling jackets for the motors for consistent results. I thought someone would have mentioned this before me. I would also use something like 1.3mm Marlow Kiteline Race SK99 dyneema and eye splice on the connection to the bed and pulley. The connector you choose is fighting you.
At this point the accel numbers could be measured in Km/s² or mach(345m/s). The nanotech motor with the 60mm pulley basicly hits mach 5.5/s acceleration (mach 5.539/s or 1900m/s²)
Hey, so I'm surprised you kept increasing pulley size. The torque of the weight you have to move is higher with larger pulleys. Also, the force act at a different height on the pulley, where the built platform is the same. So I only ever make the pulleys smaller. Also, you mentioned the opposite pulley is off. So it's all on one pulley. What's the reason you didn't use a coupled system, so the opposite stepper runs in reverse, not off. Pulling the "on" pulley from the top? CoreXY uses both motors at once for that reason.
Yes, but Core XY also relies on using guide rails and subsequently linear bearings of some sort. I got rid of everything you dont need and can build the lightest setup possible.
@@Roetz40 right I understand that. I wasn't suggesting using a CoreXY setup. Just the reasoning for use of 2 motors to double the power along each axis.
if i understand it correctly wouldnt you reduce the gap between just pully and simulated weight if you use 8 motos. So you only have half of the inertia per motor?
@Jan Du hast bei 15:55 min ein Problem: Wenn die Neodym-Magnete erst einmal heiß geworden sind, dann verlieren die auch Ihr magnetisches Feld (Magnetkraft). Du musst also von Anfang an aktiv kühlen.
Ich bin hier im Bereich wo neodym noch keine Probleme machen sollte. Mein Flaschenhals ist der Kunststoff der weich wird und dann verändern sich alle Abmaße im System. Aber ansonsten hast du recht ;)
@@BlackHeartScyther exactly, it is just meters. But I see this a lot. Simon Vez, for example. Maybe that is an assumption that audience is lazy or numbers do not look as impressive anymore.
It kinda makes sense that you will get better acceleration from a smaller pulley thanks to the mechanical advantage you gain. you get more torque but less speed/ distance per rpm
don't you have a problem with inertia at these accélérations? if so you should reduce the moment by make mass lighter at the edges... less inertia moment need less torque to accelerate.. test 3 arms instead of 5, holes... every engineering solution to lower the moment...it should help you more than augmenting the torque... and if you have more torque it will be beneficial... but for now each cm "consume a part of newtons... this explain more the difference between poulies in my opinion...
Пока нет бенчи - нет бенчи. Очень много систем, способных к быстрым и точным движениям. Но бенчи не получаются по одной проблеме - плавление и кристализация пластика. Не быстрое движение системы.
Looks like way too much vibration oise to print accurately. Probably a gimble driven using a pair of Ball screws which can probably be driven to around 400 to 800 IPM. Another issue is they speed of the print head, & cooling time of the plastic. You probably need some method for active cooling, like an air knife.
@@Roetz40 Yes, but you never get the stability needed using string positioning as well as too much error from the strings flexing. Gear racks would be faster than ball screws, but there will be a lot of backlash. PID with Position scales could help reduce backlash.
This is the difference between somebody who chose engineering vs a true engineer. If you love the iterative testing, finding the sweet spot in every area of your design, making spreadsheets and graphs (🤓🥸🤩), finding the problem you should've seen in the initial design but didn't (and the one you overestimated and wasted time on), the whole challenge of it.... An engineer ought to come home smelling of solder smoke, cutting fluid, and burned wires. An engineer belongs behind a bench, not a desk.
