What kind of a light? Do we have to use a bulb? What type and size?

Any kind or size light. One light or many. Think about what will impress the judges. Think about how cleverly the light (s) is (are) turned off.

Can our RGM turn off more than one light?

YES.  But the final step, must also turn off a light.

Does completing the task have to be the absolute last step?

Any steps that occur after the task has been completed do not count. However, you are free to have
steps after the task is completed, even though they do not count toward your total number of steps.

Can we utilize a human in our machine?

Yes. Max 1 per machine and human must be a registered team member. A person may start the machine.
A person may be in the machine. If they touch anything in order to effect a transfer of energy, that will be scored as an intervention and lower the scoring for the machine.

We’re going to Finals! Can we add to or re-work our machine from what we had during our regional as long as it stays within the regulations?


What is repeatability?

Repeatability is how consistently a machine runs across multiple runs. A machine that works perfectly every time is ideal, but a machine that fails in the same place each time it runs is much easier to debug than a machine that fails in different places every time.

Are gasses and steam allowed to exit the boundaries of the machine?

Yes, as long as they are not hazardous. For example, fog is allowed but steam that is hot enough to burn someone is not allowed.

What is a touch/human intervention?

Any physical touching or action to continue the operation of the machine after the machine begins a Contest run. Multiple touches/human interventions on the same step in the same Contest run count as a single touch.

Example: Your machine stops because one step does not trigger another. A team member interacts with the machine through a physical touch or other device to trigger any steps that follow.

What is "a step"?

A step in the machine is a transfer of energy from one action to another action. Identical transfers of energy in succession should be counted as 1 step.

Example: A sequence of dominos hitting each other should be counted as 1 step. Counting 100 dominoes as 100 steps is repetitive and not in the spirit of Rube Goldberg.

Can a machine include a remote control device as a step in the machine?


Can a machine be started with a cell phone/remote control/RF device?


Can a team have a banner or prop outside of their area which is not used by the machine?

No items may be outside of the area used by the machine, and all items (including banners) inside the machine area count towards the dimension of the machine.

How are branching steps counted in a machine? Can they count?

No — only one linear sequence of steps can be counted. Branching steps are not advised as they make machines hard to follow.

Can I enter a machine that has been previously built and posted online?

No. All entries must be new machines built for entry into the current Contest.

Can programmable logic controllers or microcontrollers be used?

Yes, but their use must fit within the definition of a step. Steps that use controllers should be clearly stated in the written step list and include detailed information on how the transfer of energy is accomplished. Using controllers as a fail-safe is illegal and will result in disqualification.

Example: A ball falls onto a switch connected to a controller that turns on a motor.

NO: If the ball misses the switch but the controller still starts the motor, the controller is not transferring energy from one action to another action. It is acting as a fail-safe instead of a step and is illegal.

YES: If the ball hits the switch and the controller starts the motor, the controller is transferring energy from one action to another action and is consistent with the definition of a step.

Is there a limit of plugging in a power strip and running more than two cords inside our machine?

Two auxiliary umbilicals per machine. This can be air, electrical, water, etc. Once they get into the boundary of the machine, it’s part of the machine and thus able to be distributed as needed.

Can a different person or persons give the theatrical/verbal machine presentation, or does it have to be one of the two designated people that are running the machine?

It can be a different person. We don’t specify a limit, so it can be the whole team (and often is!)

May we use more than one slinky in our machine?

You may, but we suggest you only use one slinky in the coolest way possible. That’s what you’ll be judged on.