Instructables

Froggy World 1 The Catapult

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Picture of Froggy World 1   The Catapult


Froggy World is an amusement park for adventurous frogs. 

This ride is the first in a series.  Each ride receives a signal from the previous ride "You've got the frog;" and each ride signals the next that "Frog has left, you've got the frog." Eventually, the frog will be returned to the catapult (by another ride) and the cycle will repeat.

The concept for winding and releasing the catapult spring comes from Arduino Controlled Catapult by UnusualTravis
http://www.instructables.com/id/Arduino-Controlled-Catapult/


 
 
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Step 1:

Picture of
There is no real "beginning" or "end" to this amusement park, but I had to start somewhere.  The signal on Arduino pin #13 (brought low) will cause this ride to catapult the frog, return to "ready" position and notify the next ride (by a low signal on pin #11) that the frog is now in their hands.

The code "winds" the spring servo, then moves the "release servo."  The spring servo unwinds (catapult falls back to start position) and the "release servo" moves to the latch position.  Then the "frog has left" signal is activated.

#include <Servo.h>

 

Servo myservo;

Servo release;

int start = 13;

int next = 11;

int val = 0;

 

void setup ()

{myservo.attach(5);

release.attach(6);

pinMode(start, INPUT);

pinMode(next, OUTPUT);

digitalWrite(next, HIGH);

myservo.write(150);

release.write(120);

}

 

void loop ()

{val=digitalRead(start);

if(val==LOW)

{myservo.write(5);

delay(1000);

release.write(180);

delay(1000);

myservo.write(150);

delay(2000);

release.write(120);

digitalWrite(next, LOW);

delay(1000);

digitalWrite(next, HIGH);

}}

Step 2:

Picture of
I had to start somewhere . . . and this frog is actually #7 in my design sequence.

Design and 3d print files are available at:

http://www.thingiverse.com/thing:42991

Step 3:

Picture of
I used magnet wire to tie the 1/4" x 3 1/4" x .025" spring to the catapult arm.
AIBalboa249 months ago
(removed by author or community request)
MikeTheMaker (author)  AIBalboa249 months ago
OK, let's try this. Look at step #1 and remove the wires from pins 11 and 13. Remove the 10K resistor that goes to 5V.
Now, let's change the code so that the catapult only fires once (on power up or whenever you push the reset button on the Arduino).

Run the program, with nothing attached to the servos. After a few seconds, the servos will settle down. Attach the servo arms--myservo will be in the relaxed position, the release servo will be in position to hold the arm.

#include

Servo myservo;

Servo release;


void setup ()

{myservo.attach(5);

release.attach(6);


myservo.write(150);//this puts the spring in the unwound position

release.write(120);//this puts the release servo in a position to hold the catapult

}



void loop ()

{

myservo.write(5);//wind the spring

delay(1000);//give the spring time to get wound

release.write(180);//release the catch

delay(1000);//wait for the arm to fling

myservo.write(150);//return spring to released position

delay(2000);//give arm time to flop down

release.write(120);//reset catch



delay(1000000000);//wait a long long time before repeating



}
Hi! Thanks so much for the information.. I really appreciate your time and I'm really new at this. So, I am wondering if you could help point out which wires go to where on the breadboard and where I need to solder. Do I still need both servos? Also, where do the wires go on the Arduino. I'm really new to this (Like 1 week) and I'm just going by google and your pictures.. Are there any extra wires that I need to buy and what kind? Sorry for the trouble but this would help me so much! Project is due Thursday --- I've got 2 more nights. Thank you!
MikeTheMaker (author)  AIBalboa249 months ago
It looks right--a little hard to tell. Connecting the 9 volt battery should turn the Arduino on. Pushing the little brown button on the Arduino should reset it and cause it to recycle.
MikeTheMaker (author)  AIBalboa249 months ago
You need both servos--one winds the spring and the other releases the arm when the spring is wound.

Red on both servos are connected together and connected to positive on the 7.5 volt battery.

Black on both servos are connected together and connected to negative on the 7.5 volt battery. Negative on the 7.5 volt battery is connected to negative on the 9 volt battery.

Yellow on the spring winding servo is connected to pin 5 on the Arduino.

Yellow on the release servo is connected to pin 6 on the Arduino.

Positive from the 9 volt battery goes to Vin on the Arduino.

Negative from both batteries (you connected them earlier) also goes to "Gnd" on the Arduino.

You will probably need some jumper wires if you don't already have them. They have little metal pins on the ends . . . those pins will plug into the arduino sockets or the breadboard holes.

On the sides of the breadboard, everything near the red line is connected together (usually put positive from a battery there). Everything next to the blue line (between the blue line and red line) is connected together--usually put battery negative there. In the middle of the breadboard, groups of 5 pins (like A,B,C,D,E) are all connected together.

Do most of your connecting on the breadboard. You may have to solder wires from the servo and wires from the batteries (if they do not have pin connectors).
MikeTheMaker (author)  MikeTheMaker9 months ago
I've included 4 images--a servo, a jumper and an Arduino; jumper pin next to the servo connector; jumper pin in the servo connector; jumper pin connected to Arduino

Jumper pins make life a lot easier than soldering--then it is easy to change your projects around.
answers1.jpganswers2.jpganswers3.jpganswers4.jpg
Working on the connections still.. Tried re-wiring it.. http://puu.sh/4S6zI
Am i doing something wrong?
(removed by author or community request)
MikeTheMaker (author)  AIBalboa249 months ago
The first line should be:

#include <Servo.h>
AIBalboa249 months ago
(removed by author or community request)
MikeTheMaker (author)  AIBalboa249 months ago
I'll look forward to seeing the result :)
AIBalboa249 months ago
(removed by author or community request)
MikeTheMaker (author)  AIBalboa249 months ago
If you put it in series with the 4 AA (plus off the 4AA connects to negative on the one AA), then plus off the one AA goes where the 4 AA positive used to go)
AIBalboa249 months ago
oh and also the battery holder only holds 4 AA is there a way to make this work?
MikeTheMaker (author)  AIBalboa249 months ago
4 AA batteries will work (6 volts instead of 7.5). The servo pulling the spring will be slightly less powerful.
AIBalboa249 months ago
(removed by author or community request)
MikeTheMaker (author)  AIBalboa249 months ago
Looking good . . . it looks like the black servo wires are tied together, but not connected to ground . .(negative from the batteries)
Nice work!
J-Five1 year ago
I know what the frog is saying "WEEEEEEEE!!!"
MikeTheMaker (author)  J-Five1 year ago
In the next few days, the frog will "land" and have a new experience :)
By the way, how far can go
MikeTheMaker (author)  J-Five1 year ago
From carpeted floor to carpeted floor--12 to 15 feet. From a table to a tile floor, quite a bit farther.
That's what I thought any plans to make one human size that might be fun.
I better not give you any ideas.
MikeTheMaker (author)  J-Five1 year ago
I can think of a few people who need to ride the human size version . . . "The Boot" (where Froggy lands) is now ready
http://www.instructables.com/id/Froggy-World-2-The-Boot/
I would build it if there were any plans.
MikeTheMaker (author)  J-Five1 year ago
I don't know about human riders--but a catapult big enough to fling watermelons could be a treat . . . .
J-Five1 year ago
Don't quote me on this if you lengthen the lever and/or make the spring more compressed you might increase the distance.
J-Five1 year ago
TOADLY COOL!!!!
J-Five1 year ago
Cool,

Even though it should have been called frogapult!!
MikeTheMaker (author)  J-Five1 year ago
I didn't think of that . . . good name!
Thanks!!!!
Marko2381 year ago
Poor froggy :(, but guess it's the only way to get a plastic frog to jump.
MikeTheMaker (author)  Marko2381 year ago
The plastic frogs are excited to have their own amusement park--of course the plastic mice are everywhere in other parks . . .
This is awesome! I'm currently in the process of getting started with C++ and messing around with Arduino, so I'll definitely give this one a shot. Great Instructable!

GM
MikeTheMaker (author)  GorillazMiko1 year ago
Thank you! I can just barely get around in C . . . if you discover any good books on the subject, let me know.
Nice work! This is pretty cool!
MikeTheMaker (author)  SlickSqueegie1 year ago
Thanks! If all goes well, this frog will have a lot of "experiences" before returning to the catapult . . .