tag:blogger.com,1999:blog-122232832024-03-26T22:22:31.559+00:00RepRap: BlogBlog for the RepRap project at <a href="http://www.reprap.org">www.reprap.org</a> - a project to create an open-source self-copying 3D printer. To get all the early posts on this blog with all the images as a single PDF <a href="http://reprap.org/wiki/File:A_History_of_RepRap_Development.pdf">visit this page</a>.Adrian Bowyerhttp://www.blogger.com/profile/17595509188999219420noreply@blogger.comBlogger1087125tag:blogger.com,1999:blog-12223283.post-121669010021877182024-03-26T22:21:00.002+00:002024-03-26T22:21:47.200+00:00Approximate approximations<p>Following input from the OpenFlexure folk (hi Richard!) I found their code uses approximations, which line up with my IK model ... except where I forgot to rotate an axis properly. Yah. My 2-point 3D rotation maths is busted for unclear reasons, but once that's fixed we should have much more reliable positioning.</p><p>Also the OpenFlexure team might be lending some part-time support, which will be most welcome.<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-66504892233095527562024-03-25T19:24:00.003+00:002024-03-25T19:24:53.745+00:00Stage kinematics from the source<p> Dr Bowman of the OpenFlexure project was kind enough to share some simplified kinematics to me, which sound a lot easier than the approximations I was about to start on: https://openflexure.discourse.group/t/delta-stage-geometry/628, and a couple of his research team sound keen to get involved. Easter is going to get in the way I'm sure, but this should help with progress.<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-58209581052244219512024-03-24T19:51:00.001+00:002024-03-24T19:51:14.890+00:00IK Model Flaws<p>The IK model I made doesn't hold true on the mm scale. No idea why. Could be a flaw in the model, could be I've missed a mechanical aspect of the design. It might be the extension beam. So I'm going to pull that off and do some basic testing of the bare platform. If necessary I'll set up a calibration grid and fudge the control values to make it work. I'm about to get insanely busy with family stuff though, so blog postings may slow down. If anyone wants to work on the project though, I'll make time to set 'em up.<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-2736219994415771222024-03-22T21:16:00.003+00:002024-03-22T21:34:06.185+00:00Contacts unreliable but X and Z moving in sync<p>My idea of using electrical probing to find a conductive surface doesn't work. The probe bends visibly before my conductivity meter beeps. But using the small USB microscope to observe contact worked OK. Any electrical experts out there feel free to suggest solutions that don't involve wetting the contacts with mercury or gold-plating everything.<br /></p><p>So I have distance indicators on the big microscope stage. I used that to measure how far the probe moved on the Z axis when the control panel moved the mechanism by a theoretical 2mm. It moved 1.39mm +/- 0.01mm. Then I did the same with the X axis, which tries out all the trigonometry code. It moved 1.4mm +/- 0.05mm. Amazingly, actual movement coincides on both axes! If I set the GRBL steps/mm scaling right, we should be nearly there.</p><p>One problem clear in the microscope is that the probe wobbles in the XY plane when moved in the Z plane by +/- 0.05mm approx. I don't know if this is inherent to the delta stage design, or if I've stuffed something up. It might be due to the huge offset probe arm. We shall see.<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-63379036288886880122024-03-21T06:31:00.001+00:002024-03-21T06:31:29.714+00:00Remembering the Maths lessons from 40 years ago...<p>I've reached the point where the classic delta approximation isn't good enough for calibrating, so I had to make my own mathematical model. ChatGPT was of limited use, so I had to do it the old-fashioned way. Took a while (3 pages of gibberish scrawl) but I got there. I think. Long time ago, inverse kinematics not my speciality...</p><p>Next step after verifying a few test cases is to integrate that with the Control Panel and see if I can get to predictability rather than just repeatability and small increments.<br /></p><p>I've put a wire on the needle probe so I can hook it up, and I'll put a piece of copper-clad PCB on the microscope stage. This should let me figure out when I get the driver calibrated enough to run along a reasonably flat surface. That was done by poking a bit of 28ga nichrome ("vape wire") inside the needle and wiring it to the croc clip that attaches the probe to the beam.<br /></p><p>If all that works, we can try drawing things properly and I'll gitlab the Control Panel for general amusement. If it doesn't work, well, the Control Panel now has a big, red "STOP" button on it that resets the serial port and kills the GRBL driver!<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-22319202248955065592024-03-19T02:43:00.002+00:002024-03-19T02:43:57.201+00:00Roughly confirming the 3 micron accuracy<p>So, at 30,500 steps per mm in the GRBL driver I'm getting repeatable movement in 50 micron steps from the control panel. Given I'm 1/256th stepping the motors and I reckon they're only really good for 1/4 stepping, that roughly works out at 3-4 micron accuracy. This coincides with the original estimate of 3 micron precision from the first stepper motor tests under manual control.</p><p>If I try to move faster than that things slip, which is probably me overdoing the GRBL acceleration and/or max travel speed, so I'll tweak those down a bit and move on to the better microscope. Once that's set up we'll try scraping some squares out on a smear of Sharpie marker on the slide and see how square-ish things are. Probably going to need a bit of improvement to the control panel motion settings too.<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-65575248163513877592024-03-18T20:02:00.002+00:002024-03-18T20:02:23.189+00:00Unwanted adventures in inverse kinematics<p>Given up on Marlin. I've installed straight GRBL on the RAMPS assembly and have written an amateur inverse kinematics routine in python to drive GRBL X, Y & Z as the delta towers C, B, A (which seems to be engineering convention, C being on the X axis). Once I get a bit of help, it's probably best to peel the control functions out of OpenFlexure, but their codebase is somewhat impenetrable. Suggestions welcome.</p><div style="text-align: left;"><span style="font-family: Ubuntu Mono;"># Function to Calculate Tower Joint Positions:<br /># - calculate_tower_joint_positions calculates the positions of the tower joints based on the given TCP location.<br /># - It utilizes inverse kinematics to determine the heights of the tower joints above the XY plane.<br /># - The function takes a TCP location tuple (x, y, z) as input and returns a list of tower joint heights.<br />def calculate_tower_joint_positions(tcp_location):<br /> link_length = 75 # units<br /> radius = 35 # units<br /> <br /> # Calculate the distance from the TCP to each tower base<br /> tower_distances = [math.sqrt((tcp_location[0] - radius * math.cos(theta))**2 + (tcp_location[1] - radius * math.sin(theta))**2) for theta in [0, 2*math.pi/3, -2*math.pi/3]]<br /> <br /> # Calculate tower joint heights above the XY plane<br /> tower_joint_heights = [tcp_location[2] + math.sqrt(link_length**2 - dist**2) for dist in tower_distances]<br /> <br /> return tower_joint_heights<br /><br /># Test cases<br />test_locations = [(0, 0, 0), (-1, 1, 0), (0, 0, 10), (0, 20, 0), (5, 0, 0), (15, 0, 10)]<br /><br />for location in test_locations:<br /> tower_joint_heights = calculate_tower_joint_positions(location)<br /> print("TCP Location:", location)<br /> print("Tower Joint Heights:", tower_joint_heights)<br /> print()</span><br /></div><div><span style="font-family: courier;"></span></div><p><br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-63491066964908823782024-03-17T01:03:00.004+00:002024-03-17T01:03:54.543+00:00<p>The dodgy Marlin Delta configuration took off on one tower, drove it through the bottom of the stage, and snapped the anti-backlash 'O'-ring. That's going to be a beggar to replace. I thought I'd reset the axes position to current location with an G92 command, but it looks like the delta firmware may be ignoring that. More experimentation needed with the delta towers disconnected...<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-62994468064725355402024-03-16T20:48:00.003+00:002024-03-16T20:57:45.943+00:00<p>I'm starting to get some form of workbench set up here. Wide angle view of the slide, narrow angle view down the microscope (3μm/pixel), and a control panel for the Delta Stage. Still fighting the delta software and for reasons unknown the wide angle mounts the wrong way up. Will have to print a new stand for it.</p><p>Maybe I should get two and rig them to a VR headset?</p><p><br /></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgthoz4rvMNgUz7YmmFa6cqv7aUEEfGNSz1NosaHg40-FOUfWpFuC3LbiVex8xs91B7Tq6IaljsCt0j_pu0Apc593qVm9rUHiMZpXDHTjuGBJnDhpa57w6O1Vyabrgq1228GAL7ndd7TNjgl8HEYtvVn1seTMzYiS1c5Zvscz_yjCgv4n8V-OTpyF7p1AI0MQ/s1915/Visual_workbench_2024-03-17_09-42-56.png" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="1080" data-original-width="1915" height="180" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgthoz4rvMNgUz7YmmFa6cqv7aUEEfGNSz1NosaHg40-FOUfWpFuC3LbiVex8xs91B7Tq6IaljsCt0j_pu0Apc593qVm9rUHiMZpXDHTjuGBJnDhpa57w6O1Vyabrgq1228GAL7ndd7TNjgl8HEYtvVn1seTMzYiS1c5Zvscz_yjCgv4n8V-OTpyF7p1AI0MQ/s320/Visual_workbench_2024-03-17_09-42-56.png" width="320" /></a></div><br /><br /><p></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-30157113617180773312024-03-16T04:42:00.004+00:002024-03-16T07:24:08.573+00:00<p>And just when I had enough to do, it turns out that running 2 USB video cameras (microscopes) at the same time is ... a challenge.</p><p>[update] ENOBACON suggested using vlc, and that runs multiple copies and cameras, yay!<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-55100254741823185012024-03-15T23:43:00.000+00:002024-03-15T23:43:13.579+00:00<p><br /> The probe arm now has 3 supports for proper rigidity. I've turned the acceleration of the motors down a bit and we'll see how much less wobble there is during movement.</p><p>You can see my crude attachment system for the hypodermic needle that allows me to change angles and swap tips. I will be mounting the micron tips inside hypodermic needles for support, and to allow me to bend them at angles.</p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjo9RAR1fxKN3_NUvXM3bL9faeSxZsUPAv40CJicG1vyCigzdaI0ZSvoZsSrSfsBhaajL18l7KFXN-6ajVxTryya2FpmkgpjtcSTh9G9c1WVqUJxzz2dMalbGWSseIQmGYsL-R0Kze7ouPAdzy42Hfel8dlbVMYjA00A0TC3uJ-HTjizN0py0d-mQAkLvBJCw/s4608/IMG_20240316_123427_379.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="3456" data-original-width="4608" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjo9RAR1fxKN3_NUvXM3bL9faeSxZsUPAv40CJicG1vyCigzdaI0ZSvoZsSrSfsBhaajL18l7KFXN-6ajVxTryya2FpmkgpjtcSTh9G9c1WVqUJxzz2dMalbGWSseIQmGYsL-R0Kze7ouPAdzy42Hfel8dlbVMYjA00A0TC3uJ-HTjizN0py0d-mQAkLvBJCw/s320/IMG_20240316_123427_379.jpg" width="320" /></a></div>Once I've got the delta software sufficiently smoothed I might try putting Sharpie on a slide and tracing a few tracks in it to see what we get. That might help with calibration later too.<p></p><p>Yes, all this stuff is not good for accuracy. I know. However it is damned convenient for development. A "proper" prototype won't have all the bendy wirey bits. <br /></p><p><br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-20599257513974519642024-03-15T20:03:00.003+00:002024-03-15T20:03:45.322+00:00<p>One of the press-fit small gears on the NEMA17 motors broke loose, so I've remodelled the gear to take an M3 nut and set screw. The STL is here: <a href="https://www.printables.com/model/797699">https://www.printables.com/model/797699</a></p><p>There is no convenient program I've found that just allows one to noodle around directing the axis movement for a gcode device on a serial port without having to download umpteen packages. So I've written one in python that should be portable. Ugly as sin at the moment and I'll share it when it looks passable.<br /></p><p>Next up is adding a third brace to the probe arm made from 12ga wire. This should dampen vibration in all axes. Delta firmware tweaks continue, trying to get sufficient accuracy with enough range on the Delta Stage.</p><p>One annoying problem is that my USB serial connection to the RAMPS board keeps dropping out. I suspect this is due to a noisy 12V power supply, so I'll swap that out.</p><p>The shadow of the probe on the slide is proving to be so useful in guidance that I'm thinking of adding an LED on the probe arm just to cast a coloured shadow. <br /></p><p>That'll keep me busy for a while.<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-63201335934662073302024-03-14T22:46:00.003+00:002024-03-14T22:46:46.291+00:00<p>I've got the Delta Stage moving vaguely coherently by swiping a lot of Marlin Configuration from the Kossel printer configuration. Quite a bit of tweaking to do, but it moves in different directions.</p><p>The main problem is visibility. The depth of focus is poor, and the ink is not sufficiently opaque. I'll work on all that. Also I'm going to need a proper microscope calibration slide.<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-24340237996207256442024-03-12T21:27:00.001+00:002024-03-12T21:31:40.720+00:00<p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjvueOf9KEw9PyF60Ic5U3QQm2aQ4EpTga_SmVh2XQcoWcohNE2_KYRetYBpHL7ZqqQEqB_YkC0Q0pCGfSYg67zZ4kwfNqfMJiWYhZijuuRsjE33hOkJKSfzwAgTZ2dHBQ8d_KhdToDgwxeztwPWpa-P1aGoivtngrbsPE9_tNMN0T6Cnp-LrubBay6kSePrg/s4608/IMG_20240313_101129_485.jpg" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" data-original-height="3456" data-original-width="4608" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjvueOf9KEw9PyF60Ic5U3QQm2aQ4EpTga_SmVh2XQcoWcohNE2_KYRetYBpHL7ZqqQEqB_YkC0Q0pCGfSYg67zZ4kwfNqfMJiWYhZijuuRsjE33hOkJKSfzwAgTZ2dHBQ8d_KhdToDgwxeztwPWpa-P1aGoivtngrbsPE9_tNMN0T6Cnp-LrubBay6kSePrg/s320/IMG_20240313_101129_485.jpg" width="320" /></a></div><p><br />While I'm waiting for help on the Marlin Delta driver, I've soldered a 12ga wire brace to the probe arm and shortened it to 85mm. This reduces twang a *lot*. I've mounted a 22ga hypodermic on a croc clip, which clips to the probe arm so I can swap tips. The current tip is bent at 60 degrees so I can sneak it all through the lens turret on the microscope and get closer to vertical contact with the slide.</p><p>I've mixed up some machine oil with soot, which approximates the consistency of photosensitive resin. I keep it in a little dish made by wrapping an M8 nut in foil and dishing one side.</p><p>A small drop on the microscope slide serves as a reservoir, and contact with the drop gives me good feedback on the probe position (may be useful later, as is seeing the probe shadow). I'm manually tracking the probe until the driver software is sorted. Anyway, this lets me dip the 40μm probe tip then move it elsewhere and touch the slide. Bear in mind the tip is elongated on a hypodermic. This dipped tip gets me several consistent dots, about 30μm in size. Here's one viewed through the microscope:</p><div class="separator" style="clear: both; text-align: left;"><div class="separator" style="clear: both;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh2aAnMTy9rvKRQZR0rpgmsHMnPFWVdftc5blQXrqTN2G2NPd8Df0fnrSkQAmKKuTh-Bm6yzDXnyBLdwyiTVAhGz2AVxOK2L1pUi9CaH0_HnLIwKU4zieixZwyndw9TyYwe8pioagDJBbLAyZ1EwYqEgKMOg_JHhFTMv1-efLlKuSJf9QjpBkQXbz8iLUWmxg/s640/2024-03-13-084007.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="640" height="210" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh2aAnMTy9rvKRQZR0rpgmsHMnPFWVdftc5blQXrqTN2G2NPd8Df0fnrSkQAmKKuTh-Bm6yzDXnyBLdwyiTVAhGz2AVxOK2L1pUi9CaH0_HnLIwKU4zieixZwyndw9TyYwe8pioagDJBbLAyZ1EwYqEgKMOg_JHhFTMv1-efLlKuSJf9QjpBkQXbz8iLUWmxg/w281-h210/2024-03-13-084007.jpg" width="281" /></a><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh6njGDV9-Ur2R0BN_r6F_lhmHY97we4i_UObLbJcsDpDTu2LASIMAHE58w8gapBuPA9v6Hpy36htZIEwbpE0cDN30Zr4-49IY8H1hEab9VBV9zYswCguYtmSTj0iT9w5Nt3k5oh4RO-YfO7b964eZgs2LzMyYDugimIJcC2UohlKndKvE2NUJgo_9r6WgtZw/s640/2024-03-13-084007_annotated.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="480" data-original-width="640" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh6njGDV9-Ur2R0BN_r6F_lhmHY97we4i_UObLbJcsDpDTu2LASIMAHE58w8gapBuPA9v6Hpy36htZIEwbpE0cDN30Zr4-49IY8H1hEab9VBV9zYswCguYtmSTj0iT9w5Nt3k5oh4RO-YfO7b964eZgs2LzMyYDugimIJcC2UohlKndKvE2NUJgo_9r6WgtZw/w284-h213/2024-03-13-084007_annotated.jpg" width="284" /></a></div></div><br /><br /><p><br /></p><p></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-15053554529356619792024-03-11T07:04:00.001+00:002024-03-11T07:08:53.363+00:00<p>Forgot to mention the attaching the OpenFlexure Delta stage gears to a NEMA17 round shaft. Basically I warmed up the stepper shaft with a mini blowtorch and pushed the gears on. I try-fitted the motor to the Delta Stage Adaptor, added a drop of ordinary superglue, and pushed the gear into the right position. It drags the glue into the join and holds well enough for now. Probably should render something with proper inset nuts and retaining screws.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgnRwHNbf2rwcLRYSEgc5bTciyUmq5Rk7Tg9-9GorePLEY2c14d38qSDXM0fzsDmoaTNs8YJouPw3qPrTG8zJwO_SR6kebPemC7Y0ifN215dEUeTGM6CeY8upSMQhghzWh31xFocVuMYDNqNko60gSjLDzH53AlKM-IRv-Y8esRg8v1ypAbLiYUpugMH5KVIw/s4608/IMG_20240311_195931_098.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="3456" data-original-width="4608" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgnRwHNbf2rwcLRYSEgc5bTciyUmq5Rk7Tg9-9GorePLEY2c14d38qSDXM0fzsDmoaTNs8YJouPw3qPrTG8zJwO_SR6kebPemC7Y0ifN215dEUeTGM6CeY8upSMQhghzWh31xFocVuMYDNqNko60gSjLDzH53AlKM-IRv-Y8esRg8v1ypAbLiYUpugMH5KVIw/s320/IMG_20240311_195931_098.jpg" width="320" /></a></div><br /><p></p><p>Speaking of dodgy fixings, the Delta Stage is currently on a thick piece of MDF with the microscope to isolate it from the bench bending when I lean on it (yes, that causes micron-sized movement). The microscope has a decent base, but the Delta Stage feet are slick PLA so after knocking the first one onto the floor I put some double-sided sticky tape under them. Very Heath Robinson/Rube Goldberg, but seems to work quite well.<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-67314528747860129012024-03-11T06:45:00.001+00:002024-03-11T06:45:21.033+00:00<p>Well there's a surprise. The μRepRap just got a mention on Hackaday <a href="https://hackaday.com/2024/03/10/%ce%bcreprap-taking-reprap-down-to-micrometer-level-manufacturing/">https://hackaday.com/2024/03/10/%ce%bcreprap-taking-reprap-down-to-micrometer-level-manufacturing/</a> - if you're not familiar with it, it's an awesome site for hackers and makers so do visit. If you're from there and visiting here, please join in the fun.<br /></p><p>The house is without reliable power at the moment though, and the place is pulled apart for rewiring putting the brakes on dev work. 9kW of solar panels going in, so not complaining.</p><p>Still having problems getting Marlin to drive the Delta configuration at all. Might revert back to driving XYZ and get on with stiffening up the probe's arm. For initial testing I'll just be using a hypodermic point until I have a reliable Delta driver that won't try to drive one of my sub-micron probe tips through the glass slide!<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-7250702293229852062024-03-10T20:06:00.002+00:002024-03-10T20:06:59.573+00:00<p> A word or three on microscopes: You need one to work on the micron scale obviously, but which one? Well, you don't want a one-piece USB microscope. These frankly lie about magnification. A factor of "300x" compares the view of the object unaided to the view through the eyepiece. Problem: USB microscopes have no eyepiece. So the magnification they quote is totally dependent on the size of your screen, and how much you zoom the app. There is a limit, of course, on the number of pixels in the microscope camera.<br /></p><p>What you want to know is how many microns there are to a pixel on your screen. Manufacturers are reluctant to give that information. So try to get one that gives an image of a calibration slide or other known object. Knowing the resolution (typically it's a 5MP camera with about 2500 pixels across) you can calculate how many pixels go across a millimetre. To do micron scale work, you need 1,000 pixels per millimetre. This is not often found on one-piece USB microscopes.</p><p>This doesn't mean they are useless - a wider field of view is useful, they are easily positioned, and development work at 10 microns is a good starting point. However, for the fine stuff you'll probably need a "real" microscope. These can be fitted with a USB camera, but use the magnification optics of the actual microscope. I use one that has a real magnification of 500x and that lets me view microns.</p><p>Note that you will get a far better view looking through the eyepiece than you will using a USB camera on the microscope. Your retina has a much higher resolution than affordable image sensors.<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-76930702858200226272024-03-08T20:04:00.002+00:002024-03-08T20:04:36.815+00:00<p>Annoying start to μRepRap - I swept the thing off the bench and smashed it. Had to print a new Delta Stage. So I took the opportunity to reinforce the motor attachment points on the stage so that they can better hold the weight of a NEMA17 stepper motor.</p><p>Original Delta Stage here <a href="https://build.openflexure.org/openflexure-delta-stage/v1.2.2/">https://build.openflexure.org/openflexure-delta-stage/v1.2.2/</a>, my hack to it to fit NEMA17 motors here <a href="https://www.printables.com/model/797699-openflexure-delta-microscope-mods-to-fit-nema17-st">https://www.printables.com/model/797699-openflexure-delta-microscope-mods-to-fit-nema17-st</a></p><p>I am experiencing difficulties getting Marlin to drive the delta stage. Any help appreciated.<br /></p><p>On the side, I'm also assembling a new Prusa Mk4 printer which I can dedicate to this work.<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-37856036216766038342024-03-07T04:37:00.000+00:002024-03-07T04:37:05.993+00:00<p> Hello RepRappers!</p><p>It's been a while. However, there is a new RepRap project: <a href="https://reprap.org/wiki/RepRapMicron">https://reprap.org/wiki/RepRapMicron</a></p><p>The aim is to produce a RepRap capable of manufacturing things with an accuracy of better than one micron (1/1000th of a millimetre). This will use existing RepRap components, 3D printed components, and things that the average person can get hold of and afford.</p><p>Can we do it? One way to find out...</p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjDNtP-37vZddUXuoBlCMXGugKDt_BZScBYAM2Le1mx995khvZR6Ny3qUmbEGo1F6VlGAVGN-p9A561usdbIhCJPc9LZXjf7BrENl9YlYjIsaOwWL22O0sWzHWsVUB1RH9ZzgQUMsdXkrqAzRKRYWnO0N1pb-eox4lYEK8r40AFaaeqFUbdynQj54MwsidNmw/s2048/IMG_20240307_171314_855s.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="1536" data-original-width="2048" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjDNtP-37vZddUXuoBlCMXGugKDt_BZScBYAM2Le1mx995khvZR6Ny3qUmbEGo1F6VlGAVGN-p9A561usdbIhCJPc9LZXjf7BrENl9YlYjIsaOwWL22O0sWzHWsVUB1RH9ZzgQUMsdXkrqAzRKRYWnO0N1pb-eox4lYEK8r40AFaaeqFUbdynQj54MwsidNmw/s320/IMG_20240307_171314_855s.jpg" width="320" /></a></div><br /><p></p><p>Vik :v)<br /></p>vik-olliverhttp://www.blogger.com/profile/14574212494833831824noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-27699378770353651002014-04-27T20:43:00.000+01:002014-04-27T20:43:36.357+01:00Open call for AMRI 2014 Summer Fellowships<span style="font-family: inherit;">We are thrilled to announce an open call for Summer 2014 Fellowships at Advanced Manufacturing Research Institute (AMRI), hosted at Rice University in the department of Bioengineering.</span><br />
<span style="font-family: inherit;"><br /></span>
<span style="font-family: inherit;">This year there is an open call for applications for the following projects:</span><br />
<span style="font-family: inherit;"><br /></span>
<div dir="ltr" style="line-height: 1.15; margin-bottom: 0pt; margin-top: 0pt;">
<span style="background-color: transparent; color: black; font-size: 19px; font-style: normal; font-variant: normal; font-weight: bold; text-decoration: none; vertical-align: baseline; white-space: pre-wrap;"><span style="font-family: inherit;">Project 1: e-NABLE 3D Printed Prosthetic Devices</span></span></div>
<div dir="ltr" style="line-height: 1.15; margin-bottom: 0pt; margin-top: 0pt;">
<span style="font-family: inherit;"><span style="background-color: transparent; color: black; font-size: 15px; font-style: normal; font-variant: normal; font-weight: normal; text-decoration: none; vertical-align: baseline; white-space: pre-wrap;">In collaboration with the </span><a href="http://enablingthefuture.org/" style="text-decoration: none;"><span style="background-color: transparent; color: #1155cc; font-size: 15px; font-style: normal; font-variant: normal; font-weight: normal; text-decoration: underline; vertical-align: baseline; white-space: pre-wrap;">worldwide e-NABLE group</span></a><span style="background-color: transparent; color: black; font-size: 15px; font-style: normal; font-variant: normal; font-weight: normal; text-decoration: none; vertical-align: baseline; white-space: pre-wrap;">, and </span><a href="http://www.shrinershospitalsforchildren.org/en/Locations/houston/our-staff" style="text-decoration: none;"><span style="background-color: transparent; color: #1155cc; font-size: 15px; font-style: normal; font-variant: normal; font-weight: normal; text-decoration: underline; vertical-align: baseline; white-space: pre-wrap;">Gloria Gogola, M.D.</span></a><span style="background-color: transparent; color: black; font-size: 15px; font-style: normal; font-variant: normal; font-weight: normal; text-decoration: none; vertical-align: baseline; white-space: pre-wrap;"> at </span><a href="http://www.shrinershospitalsforchildren.org/Locations/houston" style="text-decoration: none;"><span style="background-color: transparent; color: #1155cc; font-size: 15px; font-style: normal; font-variant: normal; font-weight: normal; text-decoration: underline; vertical-align: baseline; white-space: pre-wrap;">Shriners Hospital for Children</span></a><span style="background-color: transparent; color: black; font-size: 15px; font-style: normal; font-variant: normal; font-weight: normal; text-decoration: none; vertical-align: baseline; white-space: pre-wrap;">, Fellows will aid in the design, 3D printing, testing, and refinement of open-source prosthetic hand and finger designs. This unique fellowship will bring 3D printing into the clinical setting, working closely with Dr. Gogola and her patients in need.</span></span></div>
<b id="docs-internal-guid-f1d8e3de-a4b4-b641-974f-785f9e83a21e" style="font-weight: normal;"><span style="font-family: inherit;"><br /></span></b>
<div dir="ltr" style="line-height: 1.15; margin-bottom: 0pt; margin-top: 0pt;">
<span style="background-color: transparent; color: black; font-size: 19px; font-style: normal; font-variant: normal; font-weight: bold; text-decoration: none; vertical-align: baseline; white-space: pre-wrap;"><span style="font-family: inherit;">Project 2: Selective Laser Sintering (SLS)</span></span></div>
<div dir="ltr" style="line-height: 1.15; margin-bottom: 0pt; margin-top: 0pt;">
<span style="font-family: inherit;"><span style="font-size: 15px; text-indent: 36pt; vertical-align: baseline; white-space: pre-wrap;">Fellows will augment and refine the </span><a href="http://reprap.org/wiki/OpenSLS" style="line-height: 1.15; text-decoration: none; text-indent: 36pt;"><span style="color: #1155cc; font-size: 15px; text-decoration: underline; vertical-align: baseline; white-space: pre-wrap;">open SLS design</span></a><span style="font-size: 15px; text-indent: 36pt; vertical-align: baseline; white-space: pre-wrap;"> pioneered by </span><a href="https://www.youtube.com/watch?v=EE5KRSlO9rA" style="line-height: 1.15; text-decoration: none; text-indent: 36pt;"><span style="color: #1155cc; font-size: 15px; text-decoration: underline; vertical-align: baseline; white-space: pre-wrap;">Andreas Bastian last year</span></a><span style="font-size: 15px; text-indent: 36pt; vertical-align: baseline; white-space: pre-wrap;">. SLS machines typically cost $50k or more, we built ours for under $15k. This year we will focus on powder manufacturing and powder handling, as well as characterization of SLS parts via scanning electron microscopy (SEM) and mechanical testing.</span></span></div>
<b style="font-weight: normal;"><span style="font-family: inherit;"><br /></span></b>
<div dir="ltr" style="line-height: 1.15; margin-bottom: 0pt; margin-top: 0pt;">
<span style="background-color: transparent; color: black; font-size: 19px; font-style: normal; font-variant: normal; font-weight: bold; text-decoration: none; vertical-align: baseline; white-space: pre-wrap;"><span style="font-family: inherit;">Project 3: OLED 3D Photolithography of Living Tissues</span></span></div>
<div dir="ltr" style="line-height: 1.15; margin-bottom: 0pt; margin-top: 0pt;">
<span style="font-family: inherit;"><span style="font-size: 15px; vertical-align: baseline; white-space: pre-wrap;">Related to </span><a href="https://www.youtube.com/watch?v=B9Gt_oRdd5c" style="line-height: 1.15; text-decoration: none;"><span style="color: #1155cc; font-size: 15px; text-decoration: underline; vertical-align: baseline; white-space: pre-wrap;">Anderson Ta’s exciting digital light projection (DLP) photolithography</span></a><span style="font-size: 15px; vertical-align: baseline; white-space: pre-wrap;"> last year, Fellows will investigate and program organic light emitting diode (OLED) screens as a light source for 3D photolithographic printing of living tissues. Chemical functionalization of glass surfaces will also be investigated to passivate the screen surface and aid in detachment and 3D printing from the light source surface.</span></span></div>
<div>
<span style="background-color: transparent; color: black; font-size: 15px; font-style: normal; font-variant: normal; font-weight: normal; text-decoration: none; vertical-align: baseline; white-space: pre-wrap;"><span style="font-family: inherit;"><br /></span></span></div>
<span style="font-family: inherit;">Check out all the details, and be sure to apply by May 15th:</span><br />
<span style="font-family: inherit;"><a href="http://amrinstitute.org/" target="_blank">http://amrinstitute.org</a></span><br />
<div>
<span style="font-family: inherit;"><br /></span></div>
<div>
Questions can be directed to <a href="mailto:amri@rice.edu?subject=Summer%202014%20Fellowships" target="_blank">amri@rice.edu</a>.</div>
jmilhttp://www.blogger.com/profile/15928925747036467102noreply@blogger.com1tag:blogger.com,1999:blog-12223283.post-56900812326421287592014-04-08T16:43:00.002+01:002014-04-08T16:45:33.547+01:00Custom G-code Generation with MecodeIf you've ever wanted to hard-code gcode but still retain some scripting flexibility (for art, science, or engineering), Jack Minardi just posted a custom g-code generation package he's been working on... it looks great.<br />
<br />
Checkout <a href="http://reprap.org/wiki/Mecode">the RepRap wiki entry</a>
and<br />
also <a href="https://github.com/jminardi/mecode">the github repo with instructions</a><br />
<br />
This could be a big win for 3d printing sacrificial inks like <a href="http://blog.reprap.org/2012/07/on-challenge-of-3d-printing-sugar-for.html">sugars</a> and <a href="http://www.3ders.org/articles/20140220-harvard-scientists-3d-bioprint-layered-tissue-with-blood-vessels.html">pluronics</a> where each extruded filament position needs to be placed with precise (x,y,z) coordinates.
And for arcs and meanders, there are built-in functions too! Very exciting.
From the Github README:
<br />
<blockquote>
To use, simply instantiate the G object and use its methods to trace your desired tool path.</blockquote>
<code>
from mecode import G <br />
g = G() <br />
g.move(10, 10) # move 10mm in x and 10mm in y <br />
g.arc(x=10, y=5, radius=20, direction='CCW') # counterclockwise arc with a radius of 5 <br />
g.meander(5, 10, spacing=1) # trace a rectangle meander with 1mm spacing between passes <br />
g.abs_move(x=1, y=1) # move the tool head to position (1, 1) <br />
g.home() # move the tool head to the origin (0, 0) <br />
</code>
<br />
<br />
We got a chance to meet Jack at <a href="http://blog.reprap.org/2014/02/join-us-at-2014-midwest-reprap-festival.html">MRRF</a> and everyone had a great time. <a href="http://www.linkedin.com/in/jackminardi">Jack Minardi</a> is currently a Research Fellow at <a href="http://lewisgroup.seas.harvard.edu/">Lewis Lab at Harvard</a>.jmilhttp://www.blogger.com/profile/15928925747036467102noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-85689949596628185692014-02-14T00:38:00.004+00:002014-02-14T00:41:09.608+00:00Join us at 2014 Midwest RepRap Festival (MRRF), Goshen, Indiana, USA<div class="separator" style="clear: both; text-align: center;">
<a href="http://midwestreprapfest.org" target="_blank" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgpcueTP8iVbVpDsQzHuzxd0Vu7eraIsdWknENuQmBDaht1_CcczNyWlHGMjBXA8VbtAytpNoilXQ7Ig7Oycjkwx7blVdFybwxqiRRdNePgPBlwO6DYDtRR6NP9pkidInAUSchJ/s1600/header2.png" /></a></div>
<br />
<br />
I'm really looking forward to this!!<br />
<br />
<br />
<a href="http://midwestreprapfest.org">http://midwestreprapfest.org</a><br />
<br />
<div class="p1">
The 2014 Midwest RepRap Festival in Elkhart County Indiana is the place to be March 14-16th. This event is totally FREE to come and attend, there are no tickets, no entry fees, just come hang out all weekend and hang out with other 3D printer guys and gals, but please fill out the RSVP form by following the link above so we know how many people to expect. This event will feature build-events, guest speakers and more!</div>
<div class="p1">
<br /></div>
<div class="p2">
<b>Highlights of the event:</b></div>
<div class="p2">
<b><br /></b></div>
<div class="p1">
<span class="s1">STATE OF REPRAP</span> Come hear Josef Prusa speak on the state of Reprap.</div>
<div class="p1">
<span class="s1">TEST AND TUNE</span> Experts will be on hand to help you troubleshoot issues or take your prints to the next level! The event is FULL of people who want to see everyone become an expert. Whether it’s a simple question about a software setting, a new mechanical design, recommendations on where to go to get into reprap or more, don’t hesitate to ask anyone at the event.</div>
<div class="p1">
<span class="s1">MEET THE MAKERS</span> Meet some of the big names in RepRap, like MaxBots (Mendel MAX dev), Josef Prusa (Prusa Mendel/i3 and more), Logxen (Smoothieboard Dev) and many more</div>
<div class="p1">
<span class="s1">CRAZY NEW REPRAPS</span> Nicolas Seward (RepRap WALLY, SIMPSON, LISA) will be showing off his newest reprap creations, and talking about the unique features of his designs</div>
<div class="p1">
<span class="s1">BUILD EVENTS</span> More to come soon on Build events ….</div>
<div class="p1">
<span class="s1">3D PRINTING CHALLENGES</span> See some of the most difficult prints take shape over the course of the weekend, and some fun printing challenges too, like the hand-fed extruder print challenge</div>
<br />
<div class="p1">
<br /></div>jmilhttp://www.blogger.com/profile/15928925747036467102noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-20601076384285241182013-12-02T15:05:00.003+00:002014-01-01T14:56:55.096+00:00RS Components distributing RepRaps<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiMJdl9kTDKAciIIDle5XUBoN6c5eUCBo-j085Czslza4dHHIGdkAQQCgxsiTfTYm29hJlCr9NP6Aw2PsoxMGNrz_MNrP29tYLJqzHsfy70boYQtmgn6Odadp7VvLJ89lkiUUvDOQ/s1600/rs-ormerod.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiMJdl9kTDKAciIIDle5XUBoN6c5eUCBo-j085Czslza4dHHIGdkAQQCgxsiTfTYm29hJlCr9NP6Aw2PsoxMGNrz_MNrP29tYLJqzHsfy70boYQtmgn6Odadp7VvLJ89lkiUUvDOQ/s320/rs-ormerod.jpg" width="316" /></a></div>
<br />
<br />
<br />
<br />
<span id="goog_812563628">This blog is for the RepRap Project, and so I do not normally post information here about the activities of our company, <a href="http://reprappro.com/">RepRapPro Ltd</a>. See <a href="http://www.reprappro.com/blog/">our company blog </a>for that sort of thing.</span><br />
<br />
No. The reason for this post is that from today a seriously major international company - <a href="http://www.rs-components.com/index.html">RS Components</a><span id="goog_501029129"></span><span id="goog_501029130"></span>, the world’s largest distributor of electronics and<br />
maintenance products - will be stocking and selling completely open-source RepRap kits. And in the future they hope to be selling components for RepRaps. In particular they want to sell vitamins-only kits so that people can print their own RepRaps.<br />
<br />
For more details see <a href="http://www.designspark.com/eng/nodes/view/type:knowledge-item/slug:reprappro-ormerod-3d-printer-kit/">RS's blog post here</a>, and, of course, <a href="http://uk.rs-online.com/web/p/3d-printers/7952333/">their catalogue here</a>.Adrian Bowyerhttp://www.blogger.com/profile/17595509188999219420noreply@blogger.com4tag:blogger.com,1999:blog-12223283.post-58986548786861740032013-09-18T11:02:00.002+01:002013-09-18T11:02:55.927+01:00Heated Piezo for Jetting Wax (and other stuff)I'd just like to draw everyone's attention to this really nice RepRap heated (ink)jet head by Mike Alden, shown here printing wax.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh7mpI3IONpxorpV39bQXFie04ge0REbP4eTeiXbITltQolYo9gnCGNCJi1HPlK79RLloTHCF8wSSm5citjhD9wFj_1h-bb95N_Kouvkuv6AvztSlzbid-k_DPaQJNdlqbYQryyoQ/s1600/320px-Drops_On_Page_01.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh7mpI3IONpxorpV39bQXFie04ge0REbP4eTeiXbITltQolYo9gnCGNCJi1HPlK79RLloTHCF8wSSm5citjhD9wFj_1h-bb95N_Kouvkuv6AvztSlzbid-k_DPaQJNdlqbYQryyoQ/s1600/320px-Drops_On_Page_01.png" /></a></div>
<br />
<br />
<br />
<br />
<br />
<a href="http://reprap.org/wiki/Heated_Piezo_for_Jetting_Wax">Details are on the RepRap Wiki here.</a><br />
Adrian Bowyerhttp://www.blogger.com/profile/17595509188999219420noreply@blogger.com0tag:blogger.com,1999:blog-12223283.post-41718021561140046252013-09-04T20:24:00.003+01:002013-09-04T20:51:06.119+01:002013 AMRI Fellowships Wrap-Up and Final PresentationsThanks to all our supporters near and far, <a href="http://blog.reprap.org/2013/08/announcing-amri-advanced-manufacturing.html" target="_blank">AMRI 2013 summer Fellowships</a> were a tremendous success!<br />
<br />
<a href="http://amrinstitute.org/" target="_blank">We have launched the new AMRI website at AMRInstitute.org</a> and will be populating it with documentation and more formal write-ups of each Fellow over the next month or so.<br />
<div>
<br />
Read More about <a href="http://news.rice.edu/2013/09/03/rice-brc-hosts-advanced-manufacturing-research-institute-2/" target="_blank">AMRI at Rice University here</a>.<br />
Rice also did a great video about what we've been up to:<br />
<iframe allowfullscreen="" frameborder="0" height="360" src="//www.youtube.com/embed/VrXRk96VhNQ" width="480"></iframe>
<br />
<br />
<br />
You can also watch the 2013 AMRI Fellows final presentations via this youtube playlist:<br />
<iframe allowfullscreen="" frameborder="0" height="360" src="//www.youtube.com/embed/VebpbbZVL28?list=PL_jA9pfXtdcJRlV_Di1ft4Ncxmc9sqSDT" width="640"></iframe>
</div>
<div>
<br />
HUGE thanks to all of our sponsors and supporters (especially all those in the #reprap IRC channel)!! We couldn't have done it without you!</div>
<div class="Body">
<div class="Body">
<a href="http://www.ultimachine.com/" title="http://www.ultimachine.com/">Ultimachine</a></div>
<div class="Body">
</div>
<a href="http://bioe.rice.edu/" title="http://bioe.rice.edu/">Rice University</a></div>
<div class="Body">
<a href="http://bioe.rice.edu/" title="http://bioe.rice.edu/">Department of Bioengineering</a></div>
<div class="Body">
<a href="http://brc.rice.edu/" title="http://brc.rice.edu/">Bioscience Research Collaborative</a></div>
<div class="Body">
<a href="http://www.mica.edu/Academic_Services_and_Libraries/Fabrication_Studios/Digital_Fabrication_Studio.html" title="http://www.mica.edu/Academic_Services_and_Libraries/Fabrication_Studios/Digital_Fabrication_Studio.html">Maryland Institute College of Art (MICA)</a></div>
<div class="Body">
<a href="http://www.ultimaker.com/" title="http://www.ultimaker.com/">Ultimaker</a></div>
<div class="Body">
<a href="http://www.makergear.com/" title="http://www.makergear.com/">MakerGear</a></div>
<div class="Body">
<a href="http://www.seemecnc.com/" title="http://www.seemecnc.com/">SeeMeCNC</a><br />
<a href="http://www.reprapdiscount.com/" target="_blank">RepRapDiscount</a></div>
<div class="Body">
<a href="http://makerjuice.com/" title="http://makerjuice.com/">Maker Juice</a></div>
<div class="Body">
<a href="http://www.blogger.com/JohnYang.com" title="JohnYang.com">JohnYang.com</a></div>
<div class="Body">
<a href="http://www.misumiusa.com/" title="www.misumiusa.com">Misumi</a></div>
<div class="Body">
<a href="http://www.makergear.com/" title="http://www.makergear.com/">MakerGear</a></div>
<div class="Body">
<a href="http://reprap.org/" title="http://reprap.org/">RepRap.org</a><br />
<br />
We look forward to continuing the conversation about what AMRI is and what it should become. Let us know your thoughts!</div>
jmilhttp://www.blogger.com/profile/15928925747036467102noreply@blogger.com0