Re: When to make practice bots
 

We build our practice bot before the Comp bot. We do this for a couple of reasons,

1. We want our programmers to have a solid test bed as soon as possible,

2. If anything doesn't quite 'fit' right we would much rather it be on the practice bot than on the comp bot. This way we have time to fix the issue before we assemble the comp bot,

3. When be bag the robot we don't want that to be the stop working point, we want the practice bot ready to go so we have time to practice and continue working on any improvements before competition.

Re: When to make practice bots
 

Exactly my point. If it were up to me, I'd have both robots built by week one, giving us 5 weeks to perfect them both, and another 5 weeks with the practice bot.

But of course, it never does go the way we want it to. I want the actual answers, showing that you've done it, compared to what you want, showing what you could have done.


Thanks to everyone who has provided answers. I've looked into your answers, and the robots you make, and how your teams run, and after seeing what my goals for our team next year are, I've decided to build the practice bot along with the regular bot, however, we will have the practice bot always be one stage ahead of the competition bot, so we can correct for error if we need to (Like the comp bot would have a base, and the practice bot would have a base AND a shooter)

Re: When to make practice bots
 

As Pat already said, we make both robots at the same time. Make twice the parts, assemble them side by side. Quick, easy, and interesting to watch.

Re: When to make practice bots
 

This is our first year building a practice bot and we did it after are final robot was mostly finished for a few reasons. One if for some reason we couldn't build two robots we had our competition robot complete. Two we knew that there would be certain parts that we would have to take off the competition robot to make the practice robot complete, that meant we would only need to do the parts swap twice once on bag day and once at the beginning of our first competition.

Our build schedule allowed us to build our first robot in under 4 weeks, this left plenty of time to build the practice robot and get it nearly ready by Bag Day.

We were also able to practice with the real robot for as long as possible which was nice since are practice robot isn't identical because we don't have any advanced machining processes.

Re: When to make practice bots
 

Here's our schedule for the last two seasons:

Weeks 1 and 2:
Hardcore design and CAD work, resulting in a full, functioning robot model and part prints. Mock up kit chassis for programmers to start tinkering.

Weeks 3 and 4:
Fabrication, assembly and testing of practice robot. Noting design changes as we go.

Weeks 5 and 6:
Fabrication and assembly of competition robot.

The definite (and as I feel most important) advantage to building a practice bot is drive practice. Confident drivers make less errors which results in better performance on the field.

You could also say that it gives programmers more time, but you could have a 12-week build season and the programmers would still want more time. :D (sorry Tubby)

Re: When to make practice bots
 

This is the first year in which we have built a true practice bot, in other words one which is mostly the same in form and function to the competition robot. In previous years the practice robot was just a drive chassis or was significantly different from the competition robot.

This year we built the practice robot (Scotty) first, because as several posters have mentioned, it allowed us to focus on getting it running quickly and testing its components. The final robot (Mike) is somewhat different. It is an inch longer (27" vs. 26") and 4" shorter than the practice robot. The longer came because it added stability (we could move the battery further behind the rear wheels) and made the "comb" to keep the round urethane belting from walking easier to implement. The shorter came because testing on the conveyor/garage door sensor system showed it was more precise than we planned for, so we didn't need as much space as our original design indicated. The down side to these changes is that the practice bot, while very similar, is not an exact copy. The plus side is that we were able to make the kind of improvements on the design you can only make by testing it.

This process also prodded us to make the robot design more modular. The shooter/turret assembly, the conveyor and the ramp manipulating arm are all attached basically by four bolts. Take out the bolts and disconnect the quick disconnect wires and the parts come out. In the end we have built two of almost everything.

We assembled the final robot in the last week. Next year I am going to push to get it done a few days earlier than the final weekend, but the trade off has been worth it. Scotty is a fully functional robot with the same basic design as Mike, so we have been able to practice. Over spring break we will get in quite a few more hours of driving and calibrating. (Just have to remember to move the basket height up on our backboards to account for the 4" height difference.) This is particularly good this year, because both drivers are rookies to FIRST, not just rookies to driving. df

Re: When to make practice bots
 

No need for me to write anything, it's all been said already.

No matter what you're building, the second one always comes out better.
Once the drive base team has finished the "first" bot, they start immediately on the second (competition) bot, because otherwise their build season is done. Same with all the teams that follow - manipulator(s), electrical, pneumatic.

We'll even go back to the prototype but and retrofit it to be identical in function (but not necessarily as pretty) so the programmers use the exact same code on both.

That's how our drive team gets in so much practice time.