For our first project in the STEM program, we built Rube Goldberg Machines. Rube Goldberg Machines (named after the cartoonist and inventor, Rube Goldberg) are overly complex machines used to perform a simple task through many intricate processes.Our goal was to make a working Rube Goldberg Machine capable of cracking/breaking an egg through a process of 9+ steps using at least 5 simple machines with a minimum of 4 energy transfers. After many failed attempts, we built an egg-cracking machine with 17 steps utilizing 5 simple machines with 10+ energy transfers. Below is a video of our completed Rube Goldberg Machine hitting a pencil. (We forgot eggs!)
In our Rube Goldberg Project, we learned about simple machines, speed, velocity, acceleration, force, Newton's Laws, work, energy and mechanical advantage.
To build our project, one of the subjects we needed to learn about was simple machines. There are 6 types of simple machines: inclined planes, wheels and axles, pulleys, screws, levers, and wedges . Inclined planes are flat surfaces tilted at an angle to reduce force required to do work. Wheels and axles are two objects of different diameters that rotate on the same axis to multiply input force. Pulleys are essentially wheels and axles designed to use a belt across the circumference of the wheel. Screws are mechanisms that convert rotational motion to linear motion. Levers are rigid objects on a fulcrum that multiply input force. Wedges are objects that separate, lift, or hold other objects in place. In our project, we used 5 out of the 6 machines (Inclined planes, pulleys, screws, levers, and wedges).
The first main concept we had to study for our Rube Goldberg Projects was speed, velocity, and acceleration. Speed (S)is the rate of which something moves. To find speed, you divide the distance (D) an object traveled by the time (T) it took the object to travel to that distance. The unit of speed is meters per second (m/s). Velocity (V) is speed in a given direction. Since velocity is speed, we use the same formula/procedure and the same units, but add a direction. Acceleration (A) is the change in velocity over the change in time. To find acceleration you divide the change in velocity over the change in time. The units for acceleration are meters per second squared (m/s^2). (Note:A falling object accelerates due to gravity which is 9.8 m/s^2)
Another important concept we learned about was force. Forces (F) are pushes or pulls. To find the force acting on an object, you multiply its mass by its acceleration, Forces are measured in units called Newtons (N)named after Sir Issac Newton.
Sir Issac Newton also compiled three laws of motion known as "Newton's Three Laws". Newton's first law states that an object in motion stays in motion while an object at rest stays at rest unless being acted on by an outside force. This law describes inertia which is an object's resistance to changes in motion. Newton's second law states that force and acceleration are directly proportional and that acceleration and mass are inversely proportional. This means that force is equal to mass multiplied by acceleration. Newton's third law states that for every action there is an equal and opposite reaction. This means that when you sit in a chair, you push down on the chair and the chair supports you by pushing back with an equal force in the opposite direction.
We also learned about work. Work is the force exerted on an object multiplied by the distance it is moved. The unit for work is joules (J).
In addition to the above, we learned about energy. We learned about two types of energy: potential energy (PE) and kinetic energy (KE). Potential energy is energy due to the position of an object. If an object is suspended in air 2 meters above the ground, it has potential energy. Kinetic energy is energy is energy due to motion of an object. If an object is falling, it has kinetic energy. Both potential energy and kinetic energy are measured in Joules (J)
Mechanical advantage (MA) is how much easier or harder a work is with the machine compared to without the machine. There are two types of mechanical advantage. Ideal mechanical advantage is the mechanical advantage of a machine without considering friction, air resistance, and other sources of error. You calculate ideal mechanical advantage by dividing the input distance by the output distance.Actual mechanical advantage is what actually is taking place in the real world. You calculate actual mechanical advantage by dividing the force of work without the machine by the force of work with the machine or by dividing the output force by the input force.
Overall, I think that our Rube Goldberg Project was a success. On the positive side, we learned lots of new formulas (F=ma, V=D/T, etc.), we learned better cooperation skills (communication, dividing work, solving problems), we became better at handling construction tools (hammering, drilling, gluing, etc.), and we made a working product. However on the negative side, I think we could have done better by making our design look more aesthetically pleasing by using less tape, managing our time more efficiently, and planning more basic designs. In the future, I plan to keep these in mind so I can make a more elegant and efficient design quickly.
To see our presentation explaining every step of our project's history, see below and feel free to ask me any questions about anything on the forum located on the homepage or the contact form on the "About Me" page.