Does anyone have any tips to Cad and design your first FRC robot?

[Ethan Pui]

I'm having problems before i even make the drivebase!

[ctt956]

What CAD software are you using? What kind of problems are you having?

[Jay O'Donnell]

Before you get to CAD, take some time to learn about all of the parts of an FRC robot and how they interact. Learn about how much power you want from your motors (so you know how many to put in) and then learn about gearing. Look through the different available gearboxes, figure out what type of frame you want to design (this is based on your team's resources) and then draw it out on paper.

If you have more specific questions that would be a good starting point.

[jayred1127]

Tutorials and a bunch of YouTube.

Do the tutorials I'm linking below if you are using solidworks:
http://www.solidworks.com/sw/educati...-tutorials.htm


If you are using AutoDesk they also have tutorials, you just have to find them.

[hectorcastillo]

Like jayred suggested, tutorials are a great way to familiarize yourself with the software and learn whatever you don't know. You want to be familiar with assemblies and how to mate parts together. You are going to have a lot of part files for your robot. I would suggest finding a way to keep all of your parts organized with a filing and naming scheme. This includes parts you make and parts you download.

It would also be helpful to know your current skill level with parts and assemblies and what kind of build system you're using (i.e. metal tubing, sheet metal, pre-fab stock, etc.). That'll definitely help with giving you more tips that are relevant to what you need.

[Ethan Pui]

I'm using inventor
Their's just so many different types of versions of one part on Andymark
It becomes confusing really...
I'm doing this project of designing a robot for this year's game stronghold for practice. And literally last year i wasn't capable of doing much that's why i want to know how to design one from scratch!

[tjwolter]

Ethan

Mentors have to learn stuff too! In our rookie season we built with paper sketches. But since Solidworks offers free software to FRC, and I found it interesting, I took a Solidworks course and also encouraged the team to tinker with at least simple drawings. You can design non critical parts for 3D printing quite easily with this program.

The part files for recent KoP frames are available, its good practice to "assemble" one with all those darned bolt holes lined up and mated properly. You can at least then do careful measuring of internal dimensions, probably could rough in some simple manipulator assemblies. Doing motion studies is a bit higher up the skill pyramid. We have a couple of younger, smarter mentors who know how to do this but will be letting the team do what they can.

Some much prefer AutoCAD to Solidworks, its a matter of taste. But the latter is a very useful program to learn, and Solidworks appears to keep supplying teams generously year after year. What you don't get done this year you will for next.

T.Wolter

[Jaci]

Ethan,

I've forwarded on your concerns and questions to the other mentors. We'll try and cover this in more detail during our second round of CAD and Mechanical Training, as well as during build season. If you have any questions you want to clear up in person, feel free to talk any of us mentors during the second wave of preseason training.

Have a good Christmas break,
~Jaci

[Michael Hill]

It looks like SolidProfessor is giving accounts to teams again this year. However, you get 1 account per team, so I'd suggest having a mentor create an account to share with the rest of your team members (that's what we do). They have a bunch of great video tutorials on SolidWorks and Inventor (as well as other software). The lessons don't take terribly long. You could go through a whole series over the course of a few hours (which you might have over the holiday).

https://solidprofessor.typeform.com/to/ALnijp

[Sperkowsky]

I am going to post a shameless plug here.

If you are looking to learn some CAD pre-season competing in the F4 CADathon may not be a bad idea.

Here is a link about what it is https://www.chiefdelphi.com/forums/s...d.php?t=152638

We will pair you with a person or two people who have a good amount of experience in CAD and can help guide you in the right direction.

[GeeTwo]

Originally Posted by Jay O'Donnell

Before you get to CAD, take some time to learn about all of the parts of an FRC robot and how they interact. Learn about how much power you want from your motors (so you know how many to put in) and then learn about gearing. Look through the different available gearboxes, figure out what type of frame you want to design (this is based on your team's resources) and then draw it out on paper.

If you have more specific questions that would be a good starting point.

^^ THIS. So much this. ^^

In addition to spending some time learning the craft of FRC, Don't think about designing the robot until you have defined what the robot is supposed to DO. Read the manual, and figure out which specific activities will be your highest priority. DON'T TRY TO DO EVERYTHING. The average FRC game involves about 5 to 10 activities. Most veteran teams will do best by optimizing on about 3 to 6 of these, and most rookie teams on 2 to 4 if you have a solid core of mentors or 1 to 2 if not. It is much better to be able to do two things consistently than six less than half the time.

Especially assuming that you do not have the funding and/or manpower and/or equipment to build two robots, DO NOT use all six weeks to build your robot. Plan to design and build it in about three or four weeks - that means, keep it simple! Then, when your schedule slips a week or two, you will still have a week or more to do driver practice. A fair robot with a good driver will compete much better than a good robot with a fair driver.

On the drivetrain, I suggest that your rookie year you build the kit chassis, and (if you have funding and capacity), pick one or at most two "standard" upgrades to buy from AndyMark -- AFTER you have read the game rules and figured out what you are going to do. Many teams have built regional-winning robots on kit chassis with only minor modifications. In the case of 3946, our fourth year was the year that our chassis most closely resembled an unmodified KoP, and was the year we went to championships - the only mod we made was to use omni wheels instead of solid.

Back to CAD -- think about your manufacturing capabilities. If you're working with a chop saw, drill press, and hand tools, you're probably better off prototyping in lumber and then transferring your most successful design to aluminum. Scale your CAD detail so that you are not CADding anything mut minor tweaks after about week 3, because if you're still pushing bits around on a CAD past that point, those changes will probably not end up on your robot anyway.

Finally, if you do not have a mechanical engineer or solid physicist or someone who builds custom things or at least makes inventive repairs on a regular basis as a mentor, try to find one or two or six, even if you have to borrow from a nearby team! Mentors are the secret sauce of FRC - with VERY few exceptions, high school students do not have a sufficiently broad and deep array of skills to effectively compete in FRC. Make your mentors earn your trust, but somehow come to trust them.

Wait, what - borrow a mentor? Even better - borrow a whole team as a mentor. FIRST, and particularly FRC, has the concept of Gracious Professionalism as our A#1 core value. The bottom line of it is that -- except during those two and a half minutes that we're competing against each other, teams help each other -- WITH EVERYTHING. Remember that scene in the Iron Man movie where Tony tells Whiplash how to make his whips work effectively, to his own later detriment? That's us. Find a nearby team; especially your rookie year, you should be able to find a team to take you on and mentor you. If that doesn't work out, let CD be your mentors. There are scores of team mentors on here (G2 included) who just can't get enough with our own teams, and help others through their issues. Just remember - the more detail you post, the better we can help. The better you monitor your post and provide responses, the better we can help.

[NShep98]

I actually have similar questions to the OP. This past year, my team did very little CAD, save for one part machined by a sponsor. For that reason I've been trying to learn Inventor since the summer. I've got a pretty good handle on parts and assemblies at this point. My main question is: Where do you start in the project of bringing a design to a fleshed out CAD model? What sort of steps do teams take in order to manage it all?

[asid61]

I always start my design process by determining my goals. What do I want to do? How much space can I use? How fast should I be going?
Then I go into JVN Design Calculator and figure out my motors and gearings for my gearboxes. Learning how motors work and how much power/heat they make is critical to knowing what gearing to use.
I then make a layout sketch in CAD defining what the overall shape of the robot will look like. This is a single sketch that contains all the major parts of the robot.
Finally, I start making individual parts and putting them together.

For your first robot, if your team isn't strong in CAD, I would skip it at this point. With only a few weeks until build season, your time is better spent familiarizing yourself with on-paper design and accurate drawing without worrying about digital design at all. If you're doing this for yourself, then first read up on Inventor tutorials until you understand all the basics of CAD software. Then watch RAMP videos on Youtube and dig up other FRC tutorials.

[Toasty]

Originally Posted by NShep98

My main question is: Where do you start in the project of bringing a design to a fleshed out CAD model? What sort of steps do teams take in order to manage it all?

The way my team brought parts from CAD to fabrication last build season was by making engineering drawings of the parts we needed then printing them out and posting them on our whiteboard for any mechanical member on our team to then fabricate. This year we are planning on doing the same process but to also using trello to keep things more organized.

[carpedav000]

When CADing the drivetrain, make your gearboxes first. It's way easier to make the drivetrain fit around gearboxes than it is to make gearboxes fit around the drivetrain (I'm currently having this problem myself)