03-20-2009 11:44 AM

Barry Bonzack

Re: pic: Why LEGO Should Not Be In Tetrix

...Or engineer new creative ways to program and build your robot to work around the challenges and limits given to your team with your kit.

Example one: Program the robot to slow down before running into a wall.

This will only protect it in autonomous mode, a run in with another robot will still most likely make it snap. You may need to engineer a way for something to come down to protect it the rest of the match, or put it on a servo so it hides itself safely in the robot.

Example two: Don't use the Touch Sensor. The ultrasonic sensor can read walls from a short distance without running into it. Use the touch sensor as a limit switch when necessary.

03-20-2009 11:49 AM

basicxman

Re: pic: Why LEGO Should Not Be In Tetrix

Quote:

Originally Posted by Barry Bonzack ...Or engineer new creative ways to program and build your robot to work around the challenges and limits given to your team with your kit. Example one: Program the robot to slow down before running into a wall. This will only protect it in autonomous mode, a run in with another robot will still most likely make it snap. You may need to engineer a way for something to come down to protect it the rest of the match, or put it on a servo so it hides itself safely in the robot. Example two: Don't use the Touch Sensor. The ultrasonic sensor can read walls from a short distance without running into it. Use the touch sensor as a limit switch when necessary.

03-20-2009 01:16 PM

meaubry

Re: pic: Why LEGO Should Not Be In Tetrix

Many times materials are included in kits of parts that require careful planning and analysis to determine if they will "hold up" to the application and environment it will be exposed to.

That is part of the challenge.

Often, we make decisions about what parts we will use and which won't we will not use. Not all of the parts are intended or expected to fit every situation.

Embrace the challange and use this as a learning / teaching experience.

Lego parts have a place and function in the kit, but perhaps not the way you are using them.

03-20-2009 05:24 PM

Abra Cadabra IV

Re: pic: Why LEGO Should Not Be In Tetrix

I think that the Lego can hold up under pressure if the structures are designed right. Purely Lego structures aren't going to be very stable, but a smart mixture of Lego and metal will be more functional than either of the two on their own.

For example, the main structure of the claw on my team's robot is made of metal, but most of what actually touches the pucks is Lego. The result is that the metal takes all the load when we run into something, but we still have much more functionality than a purely metal claw could give us. (Our heavy robot actually tipped off the ramp and fell on the claw once but only bent it, as compared to other robots which left bits of their purely-Lego claws all over the field after every match.)

03-20-2009 05:37 PM

keehun

Re: pic: Why LEGO Should Not Be In Tetrix

I sense your frustration, but don't take it out on people here because all they are is trying to help you down the road for bigger and more important things.

I do agree that whoever or whichever group that designated items to go in the kit of parts is not dumb so don't assume that they never thought about the strength of the legos in the KOP.

Next time, just take factors such as strength in to consideration and if it falls short, engineer around the problem.

If you know the Chinese Rainbow Bridge, it takes so little wood (just enough food for the walkway) and yet it is so nicely and cleverly engineered that the forces are distributed well and it can hold a lot more weight than you ever imagined.

The amount of wood that it used should never hold that many people (the painting) or the picture below, but it is indeed, possible.

Not criticizing you that you under-thought the process of design, but merely pointing out that don't think that we don't know the strength of some lego pieces and that you can always prevent things of this nature for next time

Good luck at nationals!
Keehun
FRC Team 2502