Original Design

This is the original design (Week 1) of our intermediate Rube Goldberg Design.

1) The first action will be to catch the ball given from the previous group. This design is just meant to represent a bowl shape that will guide the first ball to the next.

2) This ball knocks off a ball that is on the front of the catching object.

3) The ball will fall onto a fulcrum, and that will lift a rod.

4) This rod will knock a stick out of place that holds a car with a needle in place.

5) The car will puncture a balloon that hold a marble.

6) The funnel which held the balloon will lead the marble to a tube (or series of tubes) that will guide the marble to the next event.

7) The marble sets off a pop-sickle stick reaction that holds a pole in place. This pole supports a ball that is twisted at the top of a pole and is falls after the reaction occurs.

8) This ball swings around the pole and picks up speed to start the event of the next group. The idea at the time was to knock down a lever of the next group.

* All of the structures were going to be supported by K'NEX.

Materials List (Week 1-2)

1. Plywood
2. Cardboard
3. Toy Cars
4. K'NEX
5. Various types of balls (heavy, small, marbles, etc.)
6. Needles
7. Balloons
8. Tubes (paper towel rolls could work)
9. Pop-sickle sticks
10. Poles (Strong and tall, and strong skinny)
11. String
12. Adhesive (tape, glue)
13. Marbles

Starting Construction of Design (Week 1-3)

First finished object: Fulcrum

Original Base for Balloon:

Original Design for Ramp:

Original Pulley Design:

Testing One Event

These are the reason a steady event needs to start each event.

It works...

Testing Another Event

After being promised it will always work.

It does work

4 Sequential Events in Place

1st Design for fulcrum in center

Altered Design

Bowline Knot

In this project, lots of things were tied.
We included this image:

And therefore we included a reference to the sight from which we found this image:

http://www.outdoors.org/publications/outdoors/2009/learnhow/tie-a-bowline-knot.cfm

These are instruction on tying a bowline knot, a knot used in our pulley system.

Popsicle Stick Chain

This video serves as a tutorial to a chain of Popsicle sticks that hold the car in place.

The main goal:

Place the Popsicle sticks on top of each other so that a major portion of weight helps to balance the next stick. This way if one is removed in the early sequence the others will also.

Event Failures (With Solutions)

Failure:
The car didn't travel in a straight line. This caused it to avoid the balloon.
Solution:
Placed a row of small Popsicle sticks along the path we wanted the car to follow (a straight line).

Failure:
The weight did not fall onto the fulcrum, to lift the Popsicle stick out of place.
Solution:
Place borders along the path the weight will fall. This lowers the area on which the weight can land.

Failure:
Needle punctured, but did not pop the balloon.
Solution:
Inflate the balloon more, to increase likelihood of it to pop. Note: Too much inflation could cause premature popping, or accidental popping.

Failure:
Final mechanism in Popsicle stick reaction did not fall.
Solution (1):
Place the final mechanism on a more precarious angle. This turned out to be inconsistent and hard to recognize.
Solution (2):
Change the design of the final mechanism in order to distribute the weight more evenly along the object. Much more reliable.

Failure:
Marble did not fall into path.
Solution:
Make sure the marble comes to rest in the balloon more. Also made use of a larger, heavier marble that was more likely to follow the path (larger volume made it less like to miss the path).

* Pictures of changes included in later posts.

Finished Result

A Closer Look

Popsicle Stick Setup:

 Ball Rolling Down Ramp: