How to teach CAD and design sense virtually

So the title says most of it. I saw the following CD thread, and I was it answered most of my questions, but some still remain

Our team aims to be teaching Onshape this offseason, however, we will almost certainly be remote. Because of this, we will have no access to our workshop for hands-on training. Teaching CAD itself I understand how to do, however teaching how to create mechanisms seems difficult. How can I teach students how to make various. We currently don’t have CNC, so the thing that I want to teach is how to make parts, and then showing them what we’re limited to. How can I possibly teach all of this without showing the limits of physical parts in our shop?

Thanks in advance!

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So, as worded, I don’t think there’s any good answer to the question.

The other thread had a number of links to online resources and youtube videos that show examples of mechanism design, and lots of background on the “why” of various aspects of doing good design.

None of them will be replacements for hands-on experience. I don’t know of any virtual resource that has the exact same impact as getting hands-on experience assembling mechanical things.

So, without shipping parts to each student… my answer is, you can’t. Your training will be missing a component it had last year. And, likely, there’s no exact substitute available.

If you want to have success as a team, you’ll need to plan around that. Scope your goals and work around the training you know you can support this fall. Maintain a positive attitude with hope, but be realistic about what you can or can’t do this year.

That being said. I think an enthusiastic leader with regular team meetings, homework assignments, and lots of interaction and display of passion for the program will go a long way in engaging new folks, even without physical things for them to tinker with.

I think if you show some videos and explain what parts are easy to make (like flat pocketed parts) and couple that with some examples of good designs/robots, you can teach CAD like normal. Work on the basics with the OnShape tutorials, have them work on something simple like a drivetrain design and a gearbox, and then you can work on more complicated designs and eventually entire robots.
Generally, it’s best to have them design something poor that you can point out the obvious flaws in, and then have them move on to more complex parts.

Strongly agree. You learn to cad by doing cad. I can’t forget my very first gearbox (the pocketing was very bad).

Also, you should have your team watch matches which top tier teams play and then use pictures of their robot or FUN’s behind the bumpers. This helps with seeing how teams design strategically. Strategic design is key to designing manipulators.

Here is the general process of manipulator design I have shared with my teammates who have asked. We set our specifications (5 balls dumped in less than one sec, intake without slowing, climb in 2 seconds and whatever). Then you look at other robots that have had similar specifications to see how they designed. For instance, this year, I looked a lot at how teams in 2012 handled that year’s challenge. Then you do your layout sketch. THis is often the most time consuming thing. It has to be really detailed. If you do correct layout sketches that are detailed, you can even save that one file a bajillion times and just extrude or create whatever features are needed. Then you have to do your assembly.

This is something I’ve been thinking about (though not as much as I maybe should be). I can’t come up with a better answer than “you need to have an understanding of everything, and then everything should just fall into place”… so I’m writing a book. Section 10 may be helpful; there are definite, identifiable ‘principles’ and rules of thumb which can be used for design.

Like many things it’s not enough to have read something; design and review is really what you need; but it can be helpful to say “here’s some guidance and principles” up front rather than simply “oh your design sucks” in post.

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This is quite a low-key way to introduce such a comprehensive resource. I hope when it is more complete it gets the attention it deserves!

I’ve been teaching CAD remotely to my team (and some mentors) since March. Keep in mind that our team is very small (around 6-7 students). We use Onshape and Microsoft Teams. I’ve been using the Onshape tutorials mostly, but I give them challenges* every now and then.

Once the student has graduated from the Onshape tutorials, we start on design problems. Design problems can be anything - robotics parts or systems, nick knacks, or fix/create something for around their house. The plan is to 3D Print their designs and ship them to the student. Again, we have a small team.

One of the biggest challenges for us was that not all our students had laptops.

Just spitballing, and I’m not sure how many students you have learning CAD or if you have the funds, but it might be possible to send each kid a CHEAP 3D printer. Some of the monoprice deals are decent and go for around $120

*The challenges are something like

  • use a part drawing to recreate the part in CAD
  • design a 3D-printable hex hub
  • take an object (water bottle, pen, whatever) and make it in CAD

Or if that’s not feasible, they could get one team 3D printer to keep at a mentor’s house during the shutdown. Kids send the mentor their files to print, mentor ships them the parts.

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