Is CAD essential to all teams?

[Charles Boehm]

Our shopmates 3130 haven't used CAD to model their robots or mechanisms for at least the last four years. Anyone who follows Minnesota's top team's knows that they have been quite successful without it. Evidently not essential, but our team finds it pretty great. Especially because we can build up relationships with sponsors making us cool fancy parts

[daliberator]

In the past two years, my team has been working to get more CAD involved in our build process. I think that if you have the time, it is an extremely valuable tool for anyone on the team to know. If a student on our team learns CAD, it allows that to articulate their ideas better, and they become more engaged with the design of the robot.
One thing that I think is very important to keep in mind is that CAD skills != mechanical design skills. CAD is not a silver bullet that will transform your team into a powerhouse. Learning it has been fun and allows people to experiment with geometries and apply their design skills in a way that could not be done on paper. It is an amazing tool for robot design, but even the best tool in the world is useless unless the person using it know what they're doing.

[346CADmen]

Is CAD essential to all teams?
No, but neither are power tools. Like power tools, it can provide improvement if used properly. The free to teams software, all, provide decent tutorials.

[wireties]

Organization, money/sponsors, mentors/teachers, and disciplined processes are all necessary to reach a high level. CAD, used productively, can move the process part of the equation to another level. CAD allows one to express ideas accurately, to see if the ideas fit into the whole and to communicate the design to helpful sheet metal and machine shop sponsors. And CAD is THE way it is done in the professional arena.

Even 2D CAD is helpful but being able to animate 3D CAD is the holy grail. Accurate animation lets you try out the geometry of basic designs w/o wasting time building them. Nothing is more demoralizing than building a elegant piece of the robot only to find out it does not fit, is too heavy, the ball does not fit etc.

[abhishekmalle]

How soon is the CAD model done during the season? Or is it a continuous process where as soon as the CAD is done, the building of that part is undertaken?

[asid61]

Originally Posted by abhishekmalle

How soon is the CAD model done during the season? Or is it a continuous process where as soon as the CAD is done, the building of that part is undertaken?

For us, it varies depending on the experience of the members. Generally as soon as the drivetrain CAD is done we machine it, but we wait to machine other things until we are sure nothing will interfere with each other.

[EricH]

We're pretty much continuous CAD/manufacture.

CAD a part, built a part. Keeps us busy...

[jman4747]

Originally Posted by abhishekmalle

How soon is the CAD model done during the season? Or is it a continuous process where as soon as the CAD is done, the building of that part is undertaken?

It depends on how you are making your parts and what your resources are. This year we acquired a sheet metal fabrication sponsor on top of milling and turning ops we already had access to. Anything we wanted done in sheet metal needed to be sent off in one big order as based on the lead time we wouldn't have parts we sent of later back in time. The milled/turned parts could be made almost on the fly and get back in less than a week so we were able to iterate more with those.

It all depends on your specific situation. And you don't have to use CAD to make a complete 3D model of the robot. Even dimensions on a 2D sketch overlaid on to the kit chassis model can be a very valuable tool during fabrication.

[Arkive]

Originally Posted by Jash_J

If I could suggest one key aspect to build season that most teams should be capable of doing, it would be prototyping. Prototyping not only allows you to determine which mechanism would be best to solve that year’s game problem, but it also allows you to refine the idea until you have the best iteration of it. If then, you would like to CAD the prototypes and integrate them into one large robot that would be ideal, as you would find any integration problems before you reach your build phase. However, please realize that if you begin to CAD without any preliminary model to base your designs off of, it will be extremely tough to have a successful build season as there may be problems that occur once you have built the CAD model of your robot.

What would you suggest as a good balance time/resource wise between CAD and prototyping. We usually put a lot of time into prototyping but then we never put it into CAD to make sure it can fit with everything else. That hits our number one problem where our robot looks less streamlined and more cheesecaked than it should.

[Jash_J]

Originally Posted by Arkive

What would you suggest as a good balance time/resource wise between CAD and prototyping. We usually put a lot of time into prototyping but then we never put it into CAD to make sure it can fit with everything else. That hits our number one problem where our robot looks less streamlined and more cheesecaked than it should.

Typically we only dedicate a week to prototyping. However you can always give or take a couple days from that time period depending on the complexity of the game. If you are able to outline clear constraints and variables during the first day or so of build season, you should be able to complete the prototyping phase in about a week. This allows you to have a good amount of time left over to CAD.

Ideally, because you stated that your team is not familiar with any CAD software, I would suggest conducting workshops over the summer, even indulge yourself in a mock 2 week build season where you prototype and CAD a robot from a previous game over the summer. This will help you familiarize yourself with how tight the process can be and if it is feasible for your team to conduct during build season.

[connor.worley]

Yes, you need CAD. You will still be stressed to the last minute of build season, but you need CAD.

[Billfred]

A few thoughts:

1) I've hung banners with thoughtfully-designed robots done with a measuring tape, angle and box aluminum, and pop rivets. I've had well-CADded and waterjetted robots miss the show. There's no magic bullet here.
2) Knowing your fabrication resources is instrumental to making any CAD work. If you can't buy or lathe a shaft to fit an application, you shouldn't be putting it in the drawing! If your machine shop's tooling has a minimum radius on cuts, make sure your lightening pattern's corners have at least that radius! Start this conversation now, and do some smaller-scale tests before betting the farm.
3) Part of legit-ness is having time to practice driving. Can you turn around a drivetrain that fast, and is it that much better than the kit drivetrain (or the kit drivetrain with some bolt-ons)? Do you have means to keep old robots together and running so the drivers can get some stick time in before this robot is together (and some time against defenders afterward)?
4) Another highly underrated part of legit-ness is just not dying. Did your robot break down this year in a match? What happened there, and how can you fix it on the next robot?

[Sid323]

As a CAD team member of Team 1683 (your friendly neighbors), we would have no problem helping your team with learning SolidWorks in a robotics context. Email me at sidharth.potdar@gmail.com and we can discuss plans if you want.

[EricH]

I would consider that CAD is essential to all teams. However, I do not necessarily consider Computer Aided Design essential to all teams.




CAD may also be Cardboard Aided Design, Crayon Aided Design, or Coffee Aided Design. I suggest avoiding the latter late at night, though--you need your sleep, and nobody really knows if it works.


What I'm getting at is that you don't have to use the computer to make your designs. You will want to do scale models or drawing of some form, and CAD can make those much easier. But, as others have noted, CAD is merely a tool. Witness: this thread.

Personally, I'm partial to using good ol' pencil and paper on occasion, at least for concept drawings. And I have been known to use Microsoft Publisher (and/or PowerPoint and/or Paint) as a CAD program. No joke.

[abhishekmalle]

Ok, ok. So I'm getting the general feel here. CAD isn't absolutely needed for a successful team and could maybe be postponed till we actually have a mentor of some sort.

To the teams that CAD:

-Is the entire robot done in CAD before the manufacturing process begins? Or is there more of a rolling system where the robot is built as the CAD is completed?

-How much of that aforementioned planning is actually useful or are you just going through the motions?

-How do you go about generating interest for CAD? At least at my school, people don't exactly turn their heads at the prospect of joining robotics to CAD.

-How many people does it take to have a reasonably sized CAD team?

To the teams that don't usually CAD:

-Do you still have the entire robot planned out on paper (including dimensions) before manufacturing?

-How much of that aforementioned planning is actually useful or are you just going through the motions?

-Are there any specific build season procedures that you go through that have helped you in the absence of CAD.


I just realized how many times I used "CAD" in this post.