miguev

Eurobricks Citizen
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Everything posted by miguev

  1. Hello! I’m not particularly proud of this Technic horror I’ve created, but I’d like to share it with you rather than keep it to myself, possibly forever. Shortly after I learned about (and supported) SBrick and MiniZip in KickStarter, I started dreaming of building powerful, compact MOCs using a new combo: PP3 NiMh battery + MiniZip + SBrick + 5292 RC Buggy Motor. This is my first attempt at it, now that Android SBrick app (1.3+) is finally usable Functions Drive: 2x 5292 RC Buggy Motor, each connected to a separate SBrick, each powered by a separate PP3 NiMh 250 mAh battery using MiniZip. Steering: PF Servo. Front suspension: independent, soft, long travel, with “fake” positive caster Rear suspension: solid axle, dragged (didn’t figure out how to do four-link) 4x Lego LED Still haven’t applied myself to learning proper bodywork, so designing my own was out of the question. I went for an easy, fairly plain one. No openable doors, bonnet or anything. I worked with these two photos and scaled for 62.4mm tires. Full size (> 1024px): 1, 2. Photos were made really quick, during a baby siesta (indoor) and in short incursions (outdoors) no more than 20 meters from home. For now, I can only dream of having more time and freedom for this :D v0.99 without stickers: v1.0 with stickers based on video: Old school navigator refused to deal with GPS and computers, wanted just a compass (70001pb02) and a map with an X that marks the spot. Smart dude, run off with the loot. Very short of creativity and sleep, the only alternative I could think of to get rid of the demonic Monster logo and brand was a rather lame one: Music Energy. Example diff: I asked friends to vote in G+ and 3 out of 4 prefer Music, but the one who prefers Monster is my the only one into LEGO. I’m divided, will probably print them and try them on, but still not sure which ones to use for filming. I started with 1 battery, 1 SBrick, 2 motors. It seemed to run well. Adding an extra battery and Sbrick seems to make it run even stronger / faster, although SBrick developer Zsolt Majoros said it shouldn’t matter. The real reason I added the extra SBrick is that “2 ports 1 function” only works in Android app when those 2 ports are on separate SBricks. You may ask why use PP3 batteries instead of the acclaimed LiPo batteries… mainly because they are expensive, and a bit of a lottery with their thermal protection. MiniZip + PP3 NiMh 250 mAh wasn’t a whole lot cheaper, but the combo is certainly more compact, half the weight and doesn’t have any thermal protection. SBricks can draw as much current as the motors want, with just a small risk of overheating and possibly catching on fire… ah well, what could possibly go wrong? I haven’t actually managed to make the batteries warm up, they get warmer when charging. One likely reason for not achieving hotness is short life, according to this battery life calculator, they’d last 3.5 minutes at 3 A, 10 minutes at 1 A, 20 minutes at 500 mA. Can someone make a better-informed / estimation of a more realistic battery life? But there are more and worse problems, for which I sure can do with your advice! Caster angle is fake, isn’t? I mean, I just shifted the upper A arms a half stud backwards, but both A arms still move vertically. I think this is why big bumps will throw the truck’s front up rather than only the front wheel/s going up. When hitting a big bump with a front wheel, the wheel will thrust up and with it the whole car will roll to the opposite side. This results in a raised rear wheel taking all torque to just spin in the air, so the car stops until the raised wheel hits the ground again. Shifting the upper A arms a half stud backwards messed with the steering geometry, so now there’s a not-so-slight bump steering. I think this, combined with the twisting effect on the solid axle, is what’s causing the truck to steer to the left when accelerating. Too bad. Motors are hard coupled on their fast output and then geared down 20:12 twice, not including the 20-tooth to differential connection. Maybe I could / should gear down 20:12 only once, haven’t had a chance to try yet. I suppose integrating the motors in the rear axle and connecting wheels directly to them would help with the last couple of problems, but couldn’t figure out how to fit that in this body just yet. I’m also concerned that if one battery drains faster, the motor (no longer) powered by it will get damaged. With each rear wheel directly on one motor, that would result in the truck going in circles, but motors wouldn’t get damaged. How bad is this? Steering with SBrick (v1.3) as a significant latency, in the time it takes from the moment I slide my finger to a side (much or little) to the moment when the PF Servo starts moving, the truck is already going the wrong way. It’s really hard to drive straight. rm8, what’s your experience regarding this latency with your Double Trouble? If anyone has not seen rm8’s Double Trouble, I’ll put it as “my dream, properly done” Thank you for reading. If you were looking for a video... EDIT(25.05.2015): slightly better pics. EDIT(26.09.2015): I’m now a little more proud of my creation, at least the suspension seems right to me: it’s long travel and soft enough to reacts promptly to bumps, but the car doesn’t sink too much on it. I dare say it works better than most others, probably because it’s much harder to this the a bigger scale most others have been working with. The car is still not really fast, so I didn’t bother measuring its speed. I did try putting less reduction in the drivetrain, but that only resulted in lower speed due to lower torque, so I reverted back to my original setup. It’s still fast enough to be impossible to drive well, specially with the terrible latency in the SBrick. Latency is not a problem with the port tester, so it doesn’t look like a hardware limitation. Anyway, it’s fast enough to be fun. Thanks to Sir Wolf’s help and support, we finally have a somewhat decent video. Enjoy! :) And we learned many things the hard way: by failing. Fake caster angle is not good, you need real caster for off-road racing. I took the idea from someone’s supercar project here (sorry, couldn’t find it again) to displace the upper suspension arm by ½ stud backwards from the lower arm (see belly shot above). That gives you quite a bit of caster angle on the wheel (or snowmobile skies) but it does not help reacting promptly to the most serious bumps. It also screws the geometry in that the gear rack should ideally be ¼ stud backwards, but it’s either 0, ½ or 1. This results in notorious bump steering: front wheels are toes out when suspension is fully extended, and toes in when fully compressed. When this adds to the torsion exerted by the powerful motors on the live axle (see in the video how left front wheel jumps up when car starts). All in all: bad Idea. Portal hubs from 8070 are not good for off-road racing, I should have used the ones from the snowmobile 42021 (2015). They are also too expensive to go on dirt with them, so I didn’t. Differential slows down or even stops the car when one rear wheel take off. I knew this was a problem with crawlers, but never imagined how bad it’d be on a trophy truck. Damn it, I’ll never do this again. Just use one motor per wheel, and accept that if one motor runs out of battery or losses signal, you might take a sharp turn or find yourself driving in circles for a little, depending how the front wheels cope with the imbalance. MiniZip are great to get “buggy-motor-grade” power in a smaller size than LiPo batteries. PPA 9V batteries can fit a width of 3 studs, so a 5x11 panel makes for a perfect home. However, MiniZip’s lack of power switch in makes it a complete hassle to replace batteries. Should keep them very easily accessible.
  2. We've discussed / ranted about the scarcity of non-vehicle sets and MOCs in the LEGO Technic world before, but today I'd like to collect pointers to them. I don't intend to build a formal index thread, but I'd be super happy if we come up with a good enough collection that makes this thread worth listing among the Notable Topics. To give you an idea of what I'm looking for, think about kids who are interested in mechanisms and gears and moving parts and so on, but tend to find vehicles boring. They see something with wheels or tracks or even wings or rotors and think "oh that just goes around but doesn't do anything interesting". They'd be more interested in "working" contraptions like loom, braiding machines, kitchen blenders, egg beaters... motorized or not. Older kids may be captivated by Mindstorms creations like those (mind bogging) from Hknssn, but younger ones may be intimidated by their complexity and the need to program them, and prefer instead mechanical contraptions without a brain. That's why I'm not initially interested in Mindstorms creation here, even though they are often the best non-vehicle creations So with that in mind, I went searched around and found mostly Nico71's creations and very few from others. Could you please help me find more? Amida's Desert Eagle's ISOGAWAYoshihito's , JamesJT's carousel JKBrickworks' Sisyphus Kinetic Sculpture, Labyrinth Marble Maze (21305) Lipko's wind-up insects (and crustacean) Nico71's first loom, pneumatic clock, braiding machine, kinetic YES/NO sculpture, kinetic clock, congreve clock, second loom, vertical ball clock, GBC modules (1, 2, 3), Christmas Santa Sleigh, mechanical calculator. PG52' Spirograph Sariel's , , , , , , Sheepo's Solar system Orrery with 8 planets, Touthomme's Galloping Horse Zblj's , , , and I'd be happy to see even silly funny builds like my own . So long as it sparkles a child's curiosity about the mechanics of it Most/all of these have appeared in Eurobricks, but I'd also be happy to see creations coming from other communities or lone builders! Thanks! EDIT #1: added photos from some of the above MOCs. And a paragraph about Mindstorms. EDIT #2: add suggestions from comments #5, #7. EDIT #3: add suggestion from comment #13. PS: Looking through the Reviews by year, the latest official set that isn't a vehicle was the tiny 1237 Asimo Robot back in 2001.
  3. I suspect it'll me mostly for 2 reasons: 1. Relatively fixed inventory and/or spare capacity in drawers. That means you don't have to reorganize your drawers often, so you end up learning where parts are, by heart. That is, so long as you use them often enough to not forget where those pesky rare parts end up in last time you reorganized... 2. Good lighting. You can see pretty well what's in transparent drawers when the light is good and you are looking at them up close, or not from afar. With a 2-year-old sleeping in my LEGO room during all of my free time, I lost 2. very quickly. Also, she's more sensitive to the rattling of LEGO parts so I can't build as actively as I could when my previous child was sleeping here ─ she wouldn't be bothered by rattling LEGO. Adding to that an increase in sleep deprivation with the inevitable decrease in creativity and appetite for creating in the first place, I ended up shifting my interest into more "childish" (easier) LEGO lines like Creator, DC, Marvel, and Star Wars. Those parts don't mix well with Technic, so I had to start a separate group of organized drawers which kept (ahem, keeps) changing often. There goes 1. Thus I got to the point where I saw the point of drawer labels, and got to work about it. The lowest effort approach I came up with (not necessarily the best) is a simple Google Spreadsheet with columns widths and rows heights adjusted to print out at exactly the sizes to fit the front of my drawers (50x24 mm and 109x50 mm). For the System / non-Technic, I also added 1-line text describing the content, because for now some of those drawers have so many different parts I can't display all of them in their drawer label. 50x24 mm label for 1 Technic part in 3 colors ─ sometimes the same part fills up 2-4 drawers, split by color: 50x24 mm label for 2 Technic parts in 4 colors: 109x50 mm label for a whole bunch of Power Functions and related electric parts: 50x24 mm labels for System parts: Images came from rebrickable.com ─easy to download and available for most colors for nearly all parts─ with a significant increase in contrast. I also tried this approach; I liked the idea, but felt lazy about tweaking it. I spent quite a number of hours to get all of this done, but hopefully will be able to reuse it easily upon reorganizing drawers. Most labels are in Gimp's .xcf format, with each part in a separate layer. The result looks nice and I feel a little accomplished; while I didn't feel creative to work a MOC, I did achieve a little something I'm happy with, and it makes my life easier: Do not let these photos deceive you: the light is really poor and labels look much less clear (much less readable) to the naked eye, despite the contrast. Oh, and I still have to find a way to keep the labels from falling towards the inside of the drawers, thus become invisible from my chair down under. Oh no! I'm gonna have nightmares about this for some time. I was thinking about handing the Saturn V rocket from a metallic ceiling by means of strong magnets and fishing nylon, but I think it'll stay in firm ground forever! Yeah, I was doing that until recently, but it doesn't work well in poor light conditions, which are the ones I have to work with (as seen above).
  4. @xlib if you're a lawyer, please let us know. Otherwise, I'd recommend against stating firmly anything about what law is or is not, or what's illegal or not. I just noticed you're the first to touch to the legal aspect of the problem at hand, and it looks like you've touched a sensitive topic ;) If you assemble your own copy of someone's model and film it yourself, it is indeed your own video. If you then omit whose model it is, that's neither illegal nor against any Terms of Service, just plainly unethical. It is not plagiarism either, unless you claim the model is of your own design. Unless you are an great filmmaker and make a video as good the original, I don't think you'd be posing any problem for anybody, as most of the audience will stay with the original designer. The problem comes when you download someone's video (specially a good one) and upload it as "yours" on Facebook, YouTube or any other site. Then you're effectively stealing content, audience and potentially ads revenue. To the best of my limited knowledge, this is not only against the Terms of Service of most sites, but also an copyright infringement, specially (or maybe only strictly so) if the content is registered as copyrighted work somewhere official like copyright.gov ─ and this is probably the main reason for content providers to react promptly to reports of copyright infringement, because they are at risk of being targeted by legal actions from content creators. Another thing: there are 2 ways to share a YouTube video on Facebook, Bricklink, this forum or anywhere else. The Good Way: take the URL of the original video and share that. In this forum, you can just paste it on your message and it'll show the video. This way, you're referencing to the original content (even if embedding it) so it's not a copyright infringement. The same goes for Facebook, Google+, etc. In other places you may need to use the "embedded code" that YouTube provides: http://www.simplehtmlguide.com/youtube.php The Bad Way: download the video (which is against the Terms of Use of YouTube) and upload it to your Facebook (which is against the Terms of Use of Facebook) and then share "your" video, without every providing the URL of the original video. That's what "freebooting" is, and it is copyright infringement. BTW, once a video is on Facebook, anybody can download it with a very simple trick, even if it's only shared with a small audience. Not a place for private videos. In this forum topic we're reporting and discussing people who do it The Bad Way. In the last of Splat's comments, he mentions that Brothers-Brick blog is doing it The Good Way.
  5. @Tommy Styrvoky sounds you're pretty advanced in learning Blender, could you recommend some good tutorials for creating animations and video effects?
  6. @Splat sounds like Blender could make your life easier I don't know how to sync it with Audacity, but I haven't found it necessary just yet. Damn, now I want a GoPro 5
  7. Thank you everyone for all the useful links, specially those for music and sound effects! I'm shooting family videos for the most part, not having much time to play with LEGO because most of my free time happens to overlap with a sleeping baby. Still, the time spent in learning to edit family videos has proven useful when filming and editing videos of LEGO models, so here what I've found so far: Camera types and settings: GoPro HERO 3+ recording at 1080p60 by default, 720p120 when slow-mo matters more than resolution ─ HERO 5 does 1080p120, yay! Fujifilm XT-2 recording at 1080p60. Lenses: 18mm f/2 and 56mm f/1.2 ─ No LEGO video with these just yet, but I'm certainly itching to make one. Shooting angles and framing: keep the camera low and level, see below. Additional equipment you use: Feiyu G3 Ultra 3-Axis gimbal to keep camera level and follow panning smoothly. Long stick with said gimbal tied to the end, to keep the camera a few cm. from the ground without killing my back. Reducing vibrations and smoothing panning, this is the best thing I've found against motion blur. Ways to attach action cameras like GoPro to your models: I use (and like) the "LEGO method" in Sariel's video. Video editing software: Blender. It looks scary, and you really can't click anywhere (or press any key) without knowing what you're doing, but Mikeycal Meyer's tutorial made it all make sense and I'm pretty happy working with Blender now. DaVinci Resolve looks great but I couldn't get it to work. After a few hours of troubleshooting, reached a dead end on Ubuntu Xenial (16.04). Video editing tips: Learn about video codecs and experiment with several tools to find the ones that work best for you. Video editing may become easier if you transcode videos beforehand, I found transcoding mine to Xvid (at very high quality) makes working with them much lighter and faster, without degradation. It also makes it easier to do slow-mo. I've read that VLC works great for transcoding videos, but I settled for ffmpeg. Royalty-free music sources: freemusicarchive.org which I found via makerbook.net/audio Any other tips to make videos better: Edit audio to remove annoying noises, and also to slow down audio for slow-mo. I use Audacity and apply effects like Noise Reduction (for background / uniform noises), Amplify (with <0 db) to reduce other noises and Change Speed (for slow-mo).
  8. @Splat what you're experiencing is called "freebooting" ─ first learnt about it 2 years ago from SmarterEveryDay; Kurzgesagt has a great summary: If your stolen video was taken down within just a few hours, it sounds like a whole lot better that what happened to SmarterEveryDay:
  9. Hello... long time no see I'm slowly getting back to Technic, and got a couple new things to try: BuWizz and SBrick+ ─ in this MOC, I'll try pushing the limits with BuWizz to drive a heavier model faster than Li-Po + SBrick can. The model of choice is this VW Golf ─ a popular sports car around my early teen years: I'm not entirely sure which model exactly is this (please let me know if I got it wrong) but it looks like it's the 1990 VW Golf Mk2 Rallye G60, indeed the Nicest One Left. Scale will be roughly 1:10 (1:9.72) as calculated using this blueprint (closest match I could find) and Sariel's model scaler assuming 62.4mm tyres. Initial goals for this model: Fast enough to be fun to drive and appreciate suspension at work. 4WD with either central differential or separate front / read drive trains. Front and rear independent double wishbone suspension. Caster angle (for real this time, not fake like in my BJ Baldwin trophy truck). Reasonably good looking body work, but lightweight. Reasonably good looking interiors, with only front seats like a real rally car. Openable bonnet and boot. A few lights. Stretch goals, harder (maybe unfeasible) at this scale: RC 2-speed gear box. Automatic 2-speed gear box. Working steering wheel. Openable doors. A lot of lights. Brakes, at least on rear axle. McPherson front suspension and dragged rear axle, like the real car. I'd like to hear from the more experienced among you, if any of the above is a bad / silly / unfeasible idea. Or if there is something else I should try, or take into account. For the front axle, I'm using 32495c01 wheel hubs (from 8070) to keep ground clearance at around 2-2.5 studs. Made a fairly compact axle, to be able to mount it at an angle, with a slightly illegal alignment (off by 0.4 mm) to achieve a small caster angle of 5.7º ─ is that too little for this kind of car? Drive train is not finished yet, and for now I'm trying the easy way: separate drive trains for front and rear axle, with 2 L motors per axle geared up 1:3. With just the front axle so far, BuWizz is able to drive this at a decent speed with a bit over 1 Kg. of load (model weighs 550 g. and I tried it with a 500 g. package of flour on top). I'm hoping there will be enough power to drive around 1.5 Kg. of model with 2 axles like that. The thin 3L LBG liftarms between suspension arms and steering links are holding a round 1x1 plate to keep the CV joints to pop, otherwise they come apart under stress. The not-so-easy way I have in mind would be 2 Buggy motors going to a central differential, maybe with a 2-speed (RC or automatic) gear box in between. I have not yet tried anything for this. So far I have a chassis built with bricks, half of which is just scaffolding for the first drive test. Since I wouldn't have decent photos any time soon, I built in MLCad the part of it that is not scaffolding and took a few snapshots: A few more snapshots in a Flickr album. Looking forward to reading your comments and suggestions
  10. Thanks guys! I hear you all against central diff so that's out. VKTechnic, your rally car had the same wheels and distance between axles as mine, but was about 4 studs narrower. Was the real car just as narrow or did you have some other reason to make it so? I had seen your axles, and liked them, but I'm hesitant to take shocks apart (done it already) for this model; don't such custom-made shocks (specially yours in the rear axle) tend to fall apart more easily under stress? I did worry about toe in/out but wasn't sure how bad it'd be, does it realistically affect handling? In any case, I tried to get rid of it and came up with this:
  11. Nicely done, and thanks for the instructions! No snow in my area yet, but hopefully I can try your MOC on snow sometime this winter.
  12. Hello! After long months of little work, I finally completed v1 of this MOC. I'm now feeling free to take it apart and move on :) Please (it looks terrible embedded). More photos in Flickr, here's a couple from yesterday: Functions: Drive (1 XL motor, connected directly to rear wheel axle) Steering (Servo motor, connected with link) Front suspension Seat suspension All mudguards are functional Front mudguard does not block wheel when suspension is fully compressed Fake engine with 4 cylinders, 2 per side, because 1 per side would've been too small Opening trunk, gives access to AAA battery box Front & rear PF lights (cable is a bit short though) This is my first "working" version, completed in January 2015. It's all original LEGO parts except for the rubber bands, which I honestly didn't bother buying, but I'm sure original ones would work. A previous version (August 2014) had a more complex drivetrain that proved pretty useless due to bevel gears snapping at the rear hub, which prevented the bike from driving and eventually turned those gears useless :/ I could make a v2 with the SBrick and MiniZip to save space and make the rear of the sidecar prettier, as well as have more power for the XL motor and hopefully driver faster. However, this would all be worth peanuts with current steering, which is too wobbly and imprecise. I haven't put much thought into improving it, but I think that'd ruin two aspects I like in this version: sidecar with PF functions is easy to de/attach and the motorbike looks good without it. What do you think?
  13. Nicely done, looks like it works like a charm. I tried something like this on Summer, but didn't quite work as nicely as yours.
  14. Well said. I'd rather flip twice or thrice as many pages than see my girls discouraged by Technic sets. I'm also happy to see the highlights for new parts in big Creator sets, they're making the building experience for my wife and I appreciate that. But still, we all prefer thin or digital instructions in this family :)
  15. If those new thicker, more luxurious books will fetch a higher price in the aftermarket in years to come, that would be about the only positive point that'd count for me. What I really dislike is the poor color quality of A model PDF instructions. I don't have room for a book on my desk, so I'm pretty much forced to use PDF instructions on my PCs screen. Sometimes I'd have a hard time trying to make room even for a tablet ─ a laptop is out of the question. I store the stapled instructions just like you. For the ticker ones, I'm using normal A4-size folders, some of which have grown real thick and I don't even have the Porsche instructions yet. Those should have came as a hardcover book, that would be my wild hope for future big set instructions. They'd be so much easier to handle and store.
  16. Stunning! I'm hard pressed to decide what is it that I find most impressive, body work or chassis... pure awesome! Can't wait for the instructions :)
  17. Thanks! I felt the style in this car was vaguely familiar, and it must be because I'd previously enjoyed building your RC Sports Car :)
  18. Great model! I'll add to my to-build list if you'd post instructions :)
  19. Stunning. Just stunning. If you're looking for another challenge, here's my dream project: EV3 riding a unicycle. I've no idea if it's possible, but it should be fun to try :)
  20. Finally got a decent photo of my LEGO corner. Vertical storage to keep things out of children reach... for the most part. Running out of space for storage, still longing for more sets and they're not small (42053, 42054, 42056)... but I think this year Olympus will take my money.
  21. That was epic, and the end was sweet!
  22. Absolutely love it! I missed it here, thanks for posting to Rebrickable, that's how I noticed it. Must build :)
  23. Great work on this small scale, love the bodywork.
  24. I only own devices running Linux and Android, so I'd hate for firmware updates to require "Windows or Mac OS X". SBrick firmware updates over bluetooth have been working well for me, and I'm very happy that no additional PC-like device is required. For stationary models, even just drawing current from a USB phone charger would be great :)