Hello,
I'm trying to design a simple game for kids, as part of a college project.
the game involves the following:
1. A Large picture of an animal, the kid puts a ball into the mouth
2. This triggers a motor (air pump) which then pushes the ball across a long tube
3. While the ball is in the tube a sound[1] is made, indicating the ball is being digested (stomach)
4. Finally the ball leaves the tube through the rear of the animal, and triggers another different sound[2].
5. The motor switches off.
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Now this is what i think i have to use, please if you think otherwise or have any more input mention it, i would greatly appreciate all helpful comments.

[1] a Motion sensor triggers a micro-controller to send a signal to an external motor.
[2] shortly after the motor is powered, the ball is pushed along the tube a digestion sound plays (i don't know how to get this)**
[3] a second motion sensor at the rear, triggers the micro-controller to power off the motor and ?plays a different sound**.

**I'm thinking to use an ISD voice chip for the sounds, any other suggestion?

 

You might be able to hack a cheap MP3 player to get the sounds.
Rather than the complication of a motor and air pump, couldn't you just use gravity to pass the ball through the tube?

 

You might be able to hack a cheap MP3 player to get the sounds.
Rather than the complication of a motor and air pump, couldn't you just use gravity to pass the ball through the tube?

I have used an ISD1700 voice coder before so i am familiar with it, I will consider an mp3 player.
As for the Gravity part, no that would kill the purpose of the project haha

 

You can do this without using microcontrollers.

 

Can you use a module for the sounds, rather than build one up from a chip - ISD1700? Google "sound module for cards" for a source of built up recordable sound modules.

 

And what's the "game" -- all the kid does is stick a ball in an animal's mouth? That's the game? If using gravity instead of an air pump would kill the purpose of the project, then what is the purpose of the project?

 

The air pushing the ball through the tube, sounds like the ball is very light. Ping pong ball?

 

I'm trying to make it as cheap as possible, but i don't think it will be functional if i depend on gravity, as the tube is very long ~1meter, and the ball is of the same material as a ping pong ball except it is just a little bigger. The whole tube/circuit etc fits behind a large board with some holes in the board where the tube goes in and out so the child can see the ball rolling.

You can do this without using microcontrollers.

I've done a good few hours of research yesterday, a PIR sensor can trigger a small motor on if i use it with a MOSFET/ JFET, so maybe i wont need a microcontroller for that part. but I still have to consider the sounds.

I'll have a look at hacking an MP3 or a sound card module today hopefully that would eliminate the function of the ISD chip

 

the tube is very long ~1meter

Have you considered making it from several shorter sections, arranged in zig-zag fashion? To a kid it would look more intestinal .

 

Buy an off-the-shelf sound recorder:

http://www.seeedstudio.com/depot/Grove-Sound-Recorder-p-904.html

http://www.dx.com/p/isd1760-audio-sound-recording-module-w-microphone-deep-blue-281926#.VGDJODTF_1o

 

Welcome to AAC.

Neat project, but like others, I'm having a hard time picturing the look and operation of the tube. If you need to drive the ball through a tube, I think you'll need to add some type of check valve to where the kid pushes the ball through (inlet), otherwise air will blow out the inlet and may not push the ball at all or force you to get a pump with a lot of pressure. I wonder if you could do this with a strong but small fan? Perhaps having the inlet tube come in at an angle to the main tube would be enough?

This could be done with or without a microcontroller (uC). Here's how I'd do it without:

Two sets of IR LED's with phototransistors connected to a toggle flip flop like a CD4013. One pair to detect the ball entering, the second pair to detect the ball exiting. The output of the CD4013 will go high once the ball passes the first pair and off once the ball passes the second pair. The output of the CD4013 is connected to the motor through a relay. This makes the assumption you will NEVER have more than one ball in the tube at any time. If that is a possibility - a good chance with a kid's game - you'll either need to add more logic or lock the inlet until the ball leaves the tube. With a check valve and enough pressure, this may be all you need.

All of the sound modules proposed so far require recording the sound with a microphone. Here's some you can load a file onto. The basic ones allow you to load up to 20 separate files and play them in order, so you could load two files and trigger it twice - once a ball is inserted and once the ball exits. This means you'd only need one module. There is another one in the link above that uses five buttons - this would allow you to control each sound individually which would be ideal if you decide to allow more than one ball in the tube at a time.

A uC would allow you a little more control and you could easily handle the logic needed to keep the motor running if more than one ball is inserted.

 

Thanks for the thoughtful replies they will help a lot.

The animal is drawn on a board [240cm X 120cm approx], the ball goes into the mouth and out the end through a long tube at the back of the board.
The tube does show around the stomach area so the child can see the ball moving, and yes it is in a Zig-Zag fashion like Alec_t mentioned above.
I think i will try to avoid sound modules, as I will be more satisfied if i create the whole thing from scratch ... A microcontroller will indeed give more control and error handling so i will try to use one

 

If you're going to use a micro then that can be programmed to create the sounds you want.
A low frequency sweep would be simple to program.
Here's a sim of the result, complete with sound effects!

(Change the .txt file extension to .wav)