How is a Robot like a Bicycle?

Well, a Bicycle can be made up of a bunch of different parts:  wheels, tires, a frame, a seat, pedals, a bell, fenders, a chain, and so on.  Some parts are always there, and some are optional; maybe your Bicycle has them, and maybe it doesn't.  Once you put all the parts together, you have a Bicycle.  You treat it as a single object.  You ride your bicycle.  You don't say "I am going to ride my bicycle frame plus all the parts attached to it."

Similarly, an FLL Robot is made up of a bunch of different parts (built from LEGO-made pieces or possibly AA batteries in a battery pack [R01 and R05]).  Once all those parts are combined with each other, that's what makes up the Robot.  Your team might use a different set of parts each time they Launch the Robot, and then the Robot would be different each time it is Launched.

Here's what the Rules say about the Robot (D04) : 

Your “Robot” is your LEGO® MINDSTORMS® controller and all the Equipment you’ve combined with it by hand which is not intended to separate from it, except by hand. 

So, why I am telling you about bicycles, when the question was about M04--Crater Crossing?
Let's say that your team has a really clever attachment arm that they use for M04.  The end of the arm supports part of the weight of the arm, and pushes down the Gate between the towers on the Craters model.
Once your team attaches that arm to the Robot (and doesn't plan to have it fall off until they take it off), then the attachment arm is part of the Robot.

M04 lets your team decide what to use as the "crossing equipment".  Your team may use the Robot, or the team may use some other thing that isn't the Robot.
If your team uses part of the Robot to cross the Craters (for example an attached arm), then the Robot is the "crossing equipment" and the entire Robot has to cross completely past the flattened Gate.

Steve Scherr
Virginia-DC FLL Referee Advisor

On Tue, Sep 18, 2018 at 7:19 PM Manish Jain <[log in to unmask]> wrote:
Hello all, 

A follow up question to M04: does the entire robot has to cross the crater or a weight bearing arm can cross the tower and then come back with the robot? It was not clear.


On Tue, Sep 11, 2018, 9:00 PM VA-DC FLL Referee Advisor <[log in to unmask]> wrote:
Once your team has successfully completed a crossing for M04, then your Robot or other agent/craft may move anywhere else on the Field.

How can you be sure?

There are several "Scoring Requirement Signals" listed at the beginning of the Missions.
M04 has two conditions marked with an asterisk (*) and in GREEN

  • Methods with an asterisk “” must be the ONLY ones used, and must be OBSERVED by the referee 
  • Within the Mission descriptions, specific scoring requirements are written in GREEN.

and no conditions underlined

  • Underlined RESULTS/CONDITIONS must be visible at the END of the match
So, in order to score for M04 there are some METHODS that your team needs to use, but there's nothing that the referee has to look for at the end of the Match.  So, once you've achieved M04 using the allowed methods, the mission will be scored as complete, no matter where the Robot or other Equipment ends up.

Steve Scherr
Virginia-DC FLL Referee Advisor

On Tue, Sep 11, 2018 at 8:39 PM Sreeram Venkataraman <[log in to unmask]> wrote:

Hello all,

 Our team had a question on M04- Crater crossing. 

The mission says, 

  • All weight-bearing features of the crossing equipment must cross 
    •  completely between the towers. 
  • Crossing must be from east to west and make it completely past the flattened Gate. 

My question whatever attachment we use "could be a weight-bearing" or something else to flatten the Gate, after it crosses the towers , does it need to stay on the other side, or can it come back along with the robot. 


LightningBotz Team 

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