Rube Goldbergs Machine

One engineering objective is to help people via technological advances. Many of these greater advances in technology can be seen in machines invented by engineers. Rube Goldberg went to school to be an engineer, and after graduating, he decided to become an artist. He drew cartoons of inventions that did simple things in very complicated ways. His inventions involved many complex systems of simple machines, all organized in logical sequences, to accomplish simple tasks. An important skill for engineers is to evaluate the design of machines for their genuine usefulness for their audiences. Often, the best design is the simplest design.Simple and compound machines are designed to make work easier. When we encounter a machine that does not fit this understanding, the so-called machine seems absurd. Through the cartoons of Rube Goldberg, you will be engaged in critical thinking about the way his inventions make simple tasks even harder to complete you will evaluate the importance and usefulness of the many machines in the world around you.

INNEHÅLL/CONTENT

For 55 years, Rube Goldberg's award winning cartoons satirized machines and gadgets that he saw as excessive. His cartoons combined simple machines and common household items to create complex, wacky and diabolically logical machines that accomplished mundane and trivial tasks.

His inventions became so widely known that Webster's Dictionary added "Rube Goldberg" to its listing, defining it as "a comically involved, complicated invention, laboriously contrived to perform a simple operation." His "inventions," drawn for our pleasure, can actually work. By inventing excessively complex ways to accomplish simple tasks, he entertained us and poked fun at the gadgets designed to make our lives easier. In his words, the machines were a "symbol of humans' capacity for exerting maximum effort to achieve minimal results."

He believed that most people preferred doing things the hard way instead of using simpler, more direct paths to accomplish goals. The resulting inventions are collections of bits and pieces, parts of now useless machines, scraped together to achieve an innovative, imaginative, yet somehow logical contraption to conquer the job at hand.

The following are examples of tasks that can be illustrated using the Rube Goldberg technique: putting toothpaste on a toothbrush; adhering a stamp to a letter; selecting, cleaning, and peeling an apple; turning on a radio; toasting a slice of bread. Can you think of your own?

Through this project we will try to answer the following questions:

• How can we build a device that incorporates all the six types of simple machines and accomplishes a basic task in no less then 10 steps?
• How can we represent the process used to complete this design from goal to feedback?
• Does the prototype accomplish the basic task in no less then 10 steps?
• How does the prototype work to accomplish this task in no less then 10 steps?
• Does or could this prototype have a practical application?
• What changes would we make to the prototype based on our testing experiences – both successes and failures - during the design process? How would you make it better, funnier, more reliable, safer? (Engineers ask these questions when they design and improve products and machines.)
• How do we use tools to shape, cut, and/or fabricate elements of the design?

MÅL/TARGET

• Explain why some engineered machines have an unquestionable benefit to people and society and others do not.
• Form a critical opinion about the importance of the everyday machines they encounter.
• Explain that mechanical advantage is not always the best way to measure the value of a machine.

MATERIAL/RESOURCES

Rube Goldberg Example Machine

Suggested materials for device building. Feel free to any  additional inexpensive supplies.

• cardboard
• Popsicle sticks
• string
• marbles
• cardboard tubes
• plastic drinking straws
• plastic beverage bottles
• dominoes
• tools such as scisssors, tape, hot glue

Let's look at this Rube Goldberg cartoon, the "Self-Operating Napkin." When an engineer designs a machine, they are concerned with how it will fit in with the owner's life or what positive meaning it will have for him. Most often, a machine must be practical in order for it to be used. What's the meaning of the self-operating napkin machine? Let's read through the step-by-step description so we can understand it better.

 As you raise a spoon of soup (A) to your mouth, it pulls a string (B), thereby jerking a ladle (C), which throws a cracker (D) past a parrot (E). The parrot jumps after the cracker, and the perch (F) tilts, upsetting seeds (G) into a pail (H). The extra weight in the pail pulls a cord (I), which opens and lights an automatic cigar lighter (J), setting off a sky-rocket (K), which causes a sickle (L) to cut string (M), causing a pendulum with an attached napkin to swing back and forth, wiping off your chin.]

Obviously, the machine is complicated. Would you have been able to decipher all of the steps without the description just by looking at the machine? The simple machines (the ladle, parrot, cigar lighter, etc.) interact with one another in a way that is not immediately apparent, and the end function of the machine is not obvious either. Until we understand what the machine does, this compound machine remains fairly meaningless—that is, it is really just a funny hat atop a man's head.

After we have read the description of the "Self-Operating Napkin," it seems that all the steps fit together, similar to all the different motions within a bicycle, where one simple machine interacts with another to contribute to some end function. Considering that a bicycle takes us from one point to another, which is quite useful, why wouldn't people find this napkin-machine useful? (Answers will vary. Although the self-operating napkin might make work easier for us by definition, it probably takes more work to merely hold the machine on your head!)

(Next, look at the "Self-Opening Umbrella" cartoon, Figure 2.)

 

Figure 2. A Rube Goldberg cartoon of a self-operating umbrella.

copyright

 

Do these cartoons remind you of machines or devices in your life? Maybe it reminds you of the new electronically powered transportation device that is supposed to whisk you around a city as you stand or an old camping tent that fits together in a way that still takes forever to figure out. It is easy to see why you would be reminded of these things by the Rube Goldberg cartoons; his images depict machines that do jobs always in the most complicated ways. Can you think of other machines that you have seen that do not have much useful meaning? (Let students think about this a moment and listen to their answers. Possible answers: Electric eraser, towel warmer, electric can opener.)

Who remembers the concept of mechanical advantage? Mechanical advantage is a mathematical expression for how much easier a machine makes work. How do we find the mechanical advantage of a compound machine? Do we simply add the mechanical advantages of each simple machine? No, we multiply the separate mechanical advantages. Engineers use the product of the values of mechanical advantage to explain why a compound machine is many times more useful than a single simple machine. Would these Rube Goldberg inventions have a small or large mechanical advantage? (Answer: Probably large, since they involve so many simple machines.) Why are they not realistic for the user? (The machines may be too complex, clunky and weigh a lot to be really useful.) Why is mechanical advantage not always the best way to measure the value of machines? (In these examples, the added complexity outweighs the benefits of the machine. A person would have to exert more effort to use the machine than is needed just to perform the simple task without the machine.)

Engineers must have clear ideas about how their machines will benefit people; otherwise, they are unlikely to be used. As suggested by the Rube Goldberg cartoons, which seem to exaggerate bad designs, engineers should aim to design machines that fit in well with a person's activities and therefore somehow improve that person's life. In general, the simplest designs are the best. Even in complex machines, the simpler the individual components, the easier it is to make the machine, and the more reliable it is. Following the lesson, students are encouraged to use their knowledge of simple and compound machines to conduct the associated activity Design and Build a Rube Goldberg.Maker Time:

You will work in teams of three or four students each. Research and plan your devices. Plan component and sketch your designs (as seen in the Figure 1 example) in advance of building. Follow the  seven-step engineering design process cycle: ask, research, imagine, plan, create, test, and improve.  Teams can document this process with the Engineering Design Process Notebook.

 

sketch detailed plans of elements of the team Rube Goldberg machine to assist in the creative process.

 

 

Most machines and mechanisms are comprised of at least one of the six basic simple machines:

• lever: consists of a beam or rod at a fixed hinge, such as a seesaw or bottle opener
• wheel and axle: the two parts rotate together with force transferring from one machine to another, such as a doorknob or waterwheel
• pulley: a wheel on an axle or shaft that supports movement and transfers power to a cable or belt, as seen in machines that use hoists
• inclined plane: also known as a ramp; a flat surface tilted at an angle that aids in raising or lowering a load; examples are wheelchair ramps and slides
• wedge: a portable inclined plane used to separate two objects; axes, saws, and chisels as well as the blade of a knife all serve this purpose
• screw: a mechanism that converts rotational motion to linear motion, such as a corkscrew

BEDÖMNING/ASSESSMENT

Rubrik 

Läroplanskopplingar

Kriterier

• Eleven kan lösa olika problem i bekanta situationer på ett i huvudsak fungerande sätt genom att välja och använda strategier och metoder med viss anpassning till problemets karaktär samt bidra till att formulera enkla matematiska modeller som kan tillämpas i sammanhanget.
• Eleven för enkla och till viss del underbyggda resonemang om val av tillvägagångssätt och om resultatens rimlighet i förhållande till problemsituationen samt kan bidra till att ge något förslag på alternativt tillvägagångssätt.
• Eleven kan lösa olika problem i bekanta situationer på ett relativt väl fungerande sätt genom att välja och använda strategier och metoder med förhållandevis god anpassning till problemets karaktär samt formulera enkla matematiska modeller som efter någon bearbetning kan tillämpas i sammanhanget.
• Eleven för utvecklade och relativt väl underbyggda resonemang om tillvägagångssätt och om resultatens rimlighet i förhållande till problemsituationen samt kan ge något förslag på alternativt tillvägagångssätt.
• Eleven kan lösa olika problem i bekanta situationer på ett välfungerande sätt genom att välja och använda strategier och metoder med god anpassning till problemets karaktär samt formulera enkla matematiska modeller som kan tillämpas i sammanhanget.
• Eleven för välutvecklade och väl underbyggda resonemang om tillvägagångssätt och om resultatens rimlighet i förhållande till problemsituationen samt kan ge förslag på alternativa tillvägagångssätt.