Electric Vehicle C

[captbilly]

gh, I faced the same issue last year. I wasn't sure if my car was going straight and my alignment was off, or my alignment was good and the car was curving. In the end, I figured it doesn't really matter. I stopped caring if my car went straight as long as it ended on the mark. So if you just set your sight and leave it, adjust your car based on that and, as long as it ends on the mark, so what if it curves?

The problem is that if it curves the amount it moves to the left or right varies with the distance to the target. I spent some time with some kids who were doing wheeled vehicle 2 years ago. They came in second at nationals that year. They had zero distance error and zero time error (and the bonus for staying within the track) but they missed the finishline (left right error) by 1-2 cm each time.

[andrewwski]

I think they should extend the center line tape past the starting line. That would make it so much easier.

[sachleen]

gh, I faced the same issue last year. I wasn't sure if my car was going straight and my alignment was off, or my alignment was good and the car was curving. In the end, I figured it doesn't really matter. I stopped caring if my car went straight as long as it ended on the mark. So if you just set your sight and leave it, adjust your car based on that and, as long as it ends on the mark, so what if it curves?

The problem is that if it curves the amount it moves to the left or right varies with the distance to the target. I spent some time with some kids who were doing wheeled vehicle 2 years ago. They came in second at nationals that year. They had zero distance error and zero time error (and the bonus for staying within the track) but they missed the finishline (left right error) by 1-2 cm each time.

Of course it will vary with the distance. That's where practice comes in. Last year, i know about how much away from the center of my target my sight had to be for it to end up on the mark and it worked well. If you keep your sight fixed and always aim it directly at the target, you'll never hit it. If you keep moving it around, you'll never hit it. If you keep it fixed and, with practice, figure out about where it needs to be at certain distances, you can easily hit it.

[captbilly]

So are you saying that you are able to reliably hit the aimpoint exactly every time? I seriously asking because I am trying to figure out what level of accuracy we need to be trying to achieve. If 1 cm of error equals 1 point, and there were teams last year who were getting better then 199, then it would seem that they are getting combined errors of less then 1 cm aiming error, 1% distance error (that should be easy) and 1 percent in timing (also pretty easy at regional and state anyway). When I watched wheeled vehicle a couple of years ago at Nationals it didn't seem like many/any teams were able to aim to less then 1 cm accuracy. I never watched electric vehicle so I don't know how accurate the aiming was in that event.

By the way was aim part of the score last year, or was it just distance time and bonus for not crossing the centerline?

[sachleen]

For me, time was the only thing that I had to worry about (yet I didn't worry about it at all) because I was confident my car could be within a 1cm radius of the target every single run. and even closer on the second run. At regionals, I was super close on the first run and made the mistake of increasing the distance set in my code and it ended up 1 or 2cm further than the target. At state, the car hit perfectly on the first and second run.

[WrightStuffMonster]

gh I love the electric vehicle! It looks great! Have you tested it yet?

[gh]

There's a video of a very short (about 1 meter) and not completely perfect run in the Image Gallery. I don't have room at home to test it, so I'm bringing it to school to do test runs. I'll probably get video for documentation purposes.

[r00bin]

OK, I'm in a really bad situation. I was using a TI DC to DC power inverter to power my lego rcx. I think I connected the power terminals the wrong way the first time and now the rcx won't start up. I tried placing 6AA batteries into the rcx however it still fails to start. Does anyone know what the problem could be? The voltage output from the TI booster is 9.7V. The TI booster and the RCX has worked perfectly in the past.

Thanks

[Dark Sabre]

If you did hook the terminals up the wrong way and try to power it, the RCX might never start up again. It did it to one of mine once.

I eventually got that RCX replaced by Lego at no cost, but I had to buy another for competition since Lego doesn't exactly overnight their replacements.

[r00bin]

If you did hook the terminals up the wrong way and try to power it, the RCX might never start up again. It did it to one of mine once.

I eventually got that RCX replaced by Lego at no cost, but I had to buy another for competition since Lego doesn't exactly overnight their replacements.

Yeah, I tried to power it....darn... Is it possiable to replace the component that died? If not is there any type of timing device I could use instead of the RCX? The purpose of the RCX was to be used as a timer to control via relays how long the motors ran for.