Final Product Video

Final Product Pictures

The final product is finished. I inserted the microphone circuit inside the doorbell so when it sounds the motor turns on. The whole machine was rebuilt to be more resistant to the wear and tear of the catapult action.  The arm is now made out of stainless steel but the ball catch is still copper. The motor has an offset wheel to turn the cabinet latch and release the arm.  The button is made out of a push light and the doorbell button. 

Progress Report 2

Mechanical Function
The first prototype is finished and has been shown to the parents of the children attending Saturday Sidekicks. The machine had to be launched manually seeing that the triggering device hasn't been completed yet. It was shooting about 15 to 20 feet with two surgical tubes attached.

There have been a few

problems which came to my attention during the

first testing phase. First the copper ring that holds the tennis ball has a tendency to bend when pushed down because the tension of the surgical tubing overcomes the strength of the copper. Also I need to have a latch that can hold the arm down and a triggering mechanism that will move that latch. I am thinking a motor with a gearbox will be sufficient in turning a latch. The problem i foresee is making a latch strong enough to hold down the tension of the surgical tube .

Electronic Triggering Mechanism

I made a triggering device that can be controlled with a switch but the efficiency of it is questionable. I attached a two washers and a gear together and attached that to a motor with gearbox. It performs the function I created it for but the motor is not strong enough to overcome the friction when used. I think a new design needs to

be made.

Progress Report 1.1

I built the throwing machine and now am working out the kinks. I decided to go with the catapult design for size and weight purposes. Using a small piece of surgical tubing, the catapult easily reaches the ten foot requirement.

During the testing phase the arm on the machine broke because there was too much tension for the strength of the wood. I am going to replace the wooden arm with either metal, for more strength, or plastic, for more pliability. Copper would be preferable because I can then attach the ball holder at the end with solder to ensure a strong hold.

From here I look to design the triggering mechanism. I have some ideas for a wireless control which would be preferable. I have been thinking about using the wireless doorbell or a remote control car to turn a small motor which could then release a latch. There are several factors we must think about when trying to do this type of triggering

mechanism.

1. Power of motor to release latch

2. Friction on latch and arm must be light enough to be moved.

3. A re-latching function for quick reset.

I am sure I'm not thinking of all the problems to be solved but these are some important ones.

Progress Report 1

So far, in our journey to build this machine, we are still in the idea phase. We have a set idea of what the mechanism is going to look like as well as the triggering mechanism (shown below). The next step is to build it. I'm sure we will run into several road blocks but that is why we will build the first prototype as soon as possible. Once we have the main launching system built then we can focus on the triggering mechanism.  The main launcher will consist of a slingshot like action which propels an object more than 10 ft consistently.  This will be built out of either PVC piping or wood.  Considering the "slinging action" will pull on the PVC piping, bending the pliable plastic, we are considering a wood construction.

The one thing we are not sure about yet is the means in which the triggering mechanism will function. It can be electronic or mechanical but I am leaning toward electronic for the ease of the user. After all this is for the Saturday Sidekicks program so the main focus should be kept with the children in mind.

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Sidekicks Project Summary

This Sidekicks Project is aimed at helping special needs children have something enjoyable to play with. Our class is competeing to build the best propulsion device that would allow a member of the sidekicks program to control its operation.

Saturday Sidekicks

The Saturday Sidekicks program focuses on building motor skills and self- esteem through participation in games, perceptual motor activities, tumbling, modified sports, dance and relaxation for all special need children.

Our Project

Our objective is to build a device that will consistently launch a ball, or any object for that matter, at least ten feet and must be operated easily by the children.

Requirements:

Ten feet minimum

Not too heavy

Easy to operate

Can't be dangerous

Must be consistent

Date Due:

The first prototype must be ready by 10/29/09.

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Engineering Science 110- Intro to Engineering