Infernal Contraptions

Infernal Contraption Icon


An Infernal Contraption is a deliberately over-engineered or overdone
machine that performs a simple task in a very complex fashion, usually 
in a chain reaction. The category is fashioned after the American 
cartoonist and inventor Rube Goldberg (1883-1970).
Be sure to read the general rules and requirements, the full category description document (which also contains generic information applicable to all categories), and the rubric for the category (all of which are available at the Judging Information page here)

Pertinent Information and Definitions

Entrants in this category are exploring imaginative, non-linear, methods to solve a problem or do a mundane task.

Project Scope

Infernal Contraptions use a sequential progression of events, which starts with a simple initialization, from then on, each action triggers one or more following actions. Finally, a clearly defined and (usually) simple task is accomplished. 

Entries in this category will make use of several types of simple machines and physical forces during their sequence of operation. Simple machines include lever, wheel, pulley, incline plane, screw, and wedge. Physical forces include inertia, gravity, friction, stored energy, combustion, etc. (note that no flames are allowed on site, combustion should only be used diagrammatically).

Advanced projects will have simultaneous actions in two or more action paths, and/or the same path will be used with different materials or different results more than one time. In addition to strictly mechanical operation, time is considered. A slow moving part or something that delays operation, while still proceeding, can add complexity.

Project Display and Description

Note: Display size is the same as all types. Larger spaces are available if requested in advance, see General Rules.

While it is appreciated, entries do not have to have the entire sequence operate at the event. But, it is strongly recommended that the display have a portion of the sequence operational or a mock-up of the complete construction.

The entry should have a diagram (illustration) of the sequence from initial step to conclusion. These illustrations should clearly define the sequence of operation, including direction of force. Entries should be documented with a written sequential procession from beginning to final step. 

If the entire sequence is built, please video the sequence of operation and post it to an internet video site (such as YouTube) and provide the link to the video as part of your display. Free WiFi is available at the venue to allow entrants to play the videos during judging, and so judges (and the public) can review them later. 

Entry, Review, and udging

Judging will include an interview period and potential additional views of the project display. Judges will use an understanding of the category, this document, the rubric, and the general rules in their evaluations. Please review these documents for other items that may be considered.

What Will be Judged

  • General rules and judging criteria
  • Sequential progression is clearly labeled with indications of simple machines and physical forces
  • Diagram of operation is complete and understandable
  • If constructed and/or video recorded, the sequence fully runs with little to no outside intervention
  • If an operational portion of sequence is displayed, it should be an important, understandable piece of the whole sequence

Additional Items That Will Affect the Review and Judging Conclusions

  • Thematic construction, grouping of materials
  • Complexity of device, including advanced concepts above
  • Duration of progression – use of timing of operation as a consideration
  • Originality of tasks, initialization, or specific steps


Other contests in this category