Project Idea Ping pong balls sorter by wieght Design a mecha

Project Idea (Ping pong balls sorter by wieght)
Design a mechanical sorter system that will sort ping pong balls into four different
classes based on their weight, i.e. very heavy, heavy, medium and light.
Project Rules
· You can use any of the following materials in your mechanical sorter system (and nothing else):
Ø Card boards        Ø Papers        Ø Tape            Ø Glue        Ø Staples
Ø Rubber bands    Ø Toothpicks        Ø Plastic        Ø Springs    Ø Threads
Ø Lego pieces (any brand)            Ø Thermocol
· The sorter system should distinguish between eight ping pong balls: 2 very heavy, 2 heavy, 2 medium and 2 light and place them in 4 separate trays.
· The very heavy ping pong balls are made from normal ping pong balls fully filled with water.
Ø The heavy ones are 2/3 filled with water.
Ø The medium ones are 1/3 filled with water.
Ø The light balls are not filled.
· A syringe can be used to fill the ping pong balls with water.
· The sorter system should have one input point to receive all eight balls and four outputs for each class of the ping pong balls.
· Each output should be marked clearly if it is for very heavy, heavy, medium or light ping pong balls.
· The balls will be stored in a cylinder open from both sides and then will be released all together.
· The judges will use the “same” random order of the 8 balls among all groups when testing the designs during the competition. The random order will not be announced earlier.
· The Judges will user their own table tennis ball.
· Each group will have a second chance to sort the balls if the system could not properly sort all 8 balls in the first chance. The group can use another model or the same model for the second trial.
· The design system must sort all 8 balls.
· The winning system is the one that has the lightest weight.
Violating any of the above rules, will lead to significant loss in project grades.

Solution

You can do it in a number of ways. One method is described below.

You can make use of the weight of the ping pong balls to sort. First you should collect the balls released in a container. You can make the container using the plastic. The container should have an opening which should be closed in spring tesion. You can make use of spring, tooth pick and cardboard to make the one way gate opening.

Now make an inclined conveyor through which the balls will run upon opening the main gate. In between the conveyor at at equal distance make three more gates to sort the balls. Inclined conveyor can be made using thermocoal with both sides closed to prevent the balls from falling through the sides.

Coming to the design the first main gate should be opened manually. The heavier ball will be travelling at a faster rate than the other balls. Thus the most heavier ball will be reaching the gate no.1. spring tension at the first gate should be set in such a way that when the heavier balls strike the gate the gate should open. And when the heavier balls go past the first gate the gate should come back to its original position. In this way the most heavier balls will be passing through all the gates and finally collected at the last tray.

The remaining balls are trapped at the first gate. Now follow the same procedure for the 1st gate also. You will be able to sort the next set of balls. Keep continuing untill all the balls are sorted.