(solved) I think I do need a geometry program ... - Page 1
Forum section: electronics / general

author: DiTBho
author_rank: Super Contributor
timestamp: September 22, 2023, 02:49:06 pm
content: I need a program that allows me to build a parallelogram, fix a point on one side, move the upper side of the parallelogram while keeping the lower side still and study the trajectory described by the reference pointWhat can I use?OpenSource, Commercial, whatever, no preference.edit:typo.

author: IanB
author_rank: Super Contributor
timestamp: September 22, 2023, 02:51:13 pm
content: Desmos?https://www.desmos.com/geometry

author: AndyBeez
author_rank: Frequent Contributor
timestamp: September 22, 2023, 04:10:52 pm
content: May I ask what a palletogram is?

author: DiTBho
author_rank: Super Contributor
timestamp: September 22, 2023, 09:30:29 pm
content: typo, parallelogram

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 22, 2023, 10:47:07 pm
content: Not sure what you mean by "study", what does the job really entail?From the quick description, this reminded me of the copy tool called a pantograph:https://en.wikipedia.org/wiki/PantographThe geometry involved is not complicated.

author: abeyer
author_rank: Frequent Contributor
timestamp: September 23, 2023, 12:42:15 am
content: Quote from: AndyBeez on September 22, 2023, 04:10:52 pmI'm pretty sure it's when your old shipping pallet starts losing nails and gets kinda skewed.

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 23, 2023, 09:26:50 pm
content: Quote from: DiTBho on September 22, 2023, 11:06:36 pmOuch, while the geometry part is relatively simple (determining the position of the various points), the cinematics are significantly less so.So you have two different challenges here.I'm not sure I fully understand what is expected from you. Aren't you mainly designing software? (Maybe not and I've missed part of your activities.) This is more of a mechanical engineering/robotics task, as far as I can tell.Are you maybe missioned to find or write some software to simulate the above system? Unless it's extremely complicated, analysing it formally would probably make more sense - but would require skills in, as I said, mechanical engineering/cinematics/ultimately robotics.

author: jpanhalt
author_rank: Super Contributor
timestamp: September 23, 2023, 10:02:40 pm
content: If you only want 2D, almost any simple CAD program should do that, and they are easy to learn. I use an ancient 2D called Graphite (Ashlar-Vellum). It started life in the 90's under a different name. My version is 2002.

author: eutectique
author_rank: Frequent Contributor
timestamp: September 23, 2023, 10:42:17 pm
content: Try MotionGenhttps://motiongen.io/

author: Someone
author_rank: Super Contributor
timestamp: September 24, 2023, 12:59:30 am
content: Quote from: SiliconWizard on September 23, 2023, 09:26:50 pmHaving followed the OPs posts, its moretinkeringdreaming about adding complexity to bicycles (in this case a derailleur). There is nothing simple or easily modelled about them.

author: Someone
author_rank: Super Contributor
timestamp: September 24, 2023, 01:02:01 am
content: Quote from: jpanhalt on September 23, 2023, 10:02:40 pmIf you need 3D, many CAD programs do that, and they are hard to use.

author: DiTBho
author_rank: Super Contributor
timestamp: September 24, 2023, 09:15:30 am
content: Quote from: Someone on September 24, 2023, 12:59:30 amOnly you know what the mechanism of a submarine has to do with the derailleur?They look alike like I look like Johnny Depp, meaning we both have dark hair

author: DiTBho
author_rank: Super Contributor
timestamp: September 24, 2023, 09:18:24 am
content: Quote from: jpanhalt on September 23, 2023, 10:02:40 pmFound, downloaded, installed.Solved the problem

author: DiTBho
author_rank: Super Contributor
timestamp: September 24, 2023, 09:22:11 am
content: Quote from: SiliconWizard on September 23, 2023, 09:26:50 pmand you think I'm a plumber?

author: DiTBho
author_rank: Super Contributor
timestamp: September 24, 2023, 09:26:30 am
content: Quote from: eutectique on September 23, 2023, 10:42:17 pmThis seems very useful, also for a small puppet animation project (for kids).Thanks

author: DiTBho
author_rank: Super Contributor
timestamp: September 24, 2023, 10:28:19 am
content: ... talking about puppets, I really like how they animated the ghost-dog in theGhostbuster Legacymovie; there are a lof of electromeccanical components and micro robotic parts inside that dog, which ultimately weighs around ~250 kgWell, I have a friend who models latex and she also knows how to paint on it, maybe we can even make the upper half-back of small latex puppet, and animate it with some RC-servo and nylon cables, paired with ad-hoc 3D-printed meccanisms.

author: Nominal Animal
author_rank: Super Contributor
timestamp: September 25, 2023, 06:47:40 am
content: Quote from: DiTBho on September 22, 2023, 02:49:06 pmI use Lego Technic to find out what I need to know, and sketch some images on pen and paper to find out how I want to experiment with that, and finally write an interactive simulation (using HTML+JS or Python3+Qt5).I always fear that if I stick to a single tool, my solution space will be limited to that of the tool. Then again, I amslow, taking much more time than "normal people" to develop things (the first time I encounter a problem or need). So maybe don't listen to me on this?

author: DiTBho
author_rank: Super Contributor
timestamp: September 27, 2023, 02:59:28 pm
content: Quote from: Nominal Animal on September 25, 2023, 06:47:40 amI pre-ordered a kit with different parts, gears, axles, electric motors and compressed air pistons!It will arrive in NovemberI hadn't thought of it, but it's a brilliant idea!

author: janoc
author_rank: Super Contributor
timestamp: September 27, 2023, 07:35:52 pm
content: If your goal is to design some sort of linkage/mechanism, you likely want to have a look at this sw:https://blog.rectorsquid.com/linkage-mechanism-designer-and-simulator/Of course, any decent CAD software (e.g. Onshape, Fusion360, etc) can do that too but the complexity and learning curve is likely much higher.