Automated Rat

You wake up in the middle of the night to the sound of your mother's shrieks. You rush into her room, and notice a creepy, hideous creature zipping about – looking for it's next prey. Only one animal is ever capable of being that ugly – the dreaded rat. Then you realise, it was just your brother playing a practical joke! In this instructable, you too will learn how to create a moving, gigantic, real-life looking rat that you can use to prank your friends and family. Good luck to you and your mischievous adventurous.

This project will require the following materials:

D.C Motors x2

Green Alligator Clip x2

White Alligator Clip x2

Attachable Wheel x4

Metal Axel Stick x2

9v Battery x2

Cardboard Box (6x11x12) x1

Metal Screws x4

Duct Tape

Screw Driver x1

Cutting Board x1

Hot Glue Gun x1

Box Cutters x1

Scissors x1

Black Cloth (40x32 cm) x1

Black pipe cleaners x10

Brown fur (40 x 32 cm) x1

Note: The colors of the wires are not essential but help both in the wiring and checking of the wires by keeping a level of organization.

1. Insert an attachable wheel into the rod sticking out of the D.C motor.
2. Locate the screw hole on the D.C motor and attachable wheel. Line them up, and insert a screw in so it goes through both objects. Tighten it with a screwdriver until tight enough. The wheel should not fall off.
3. Repeat steps 1 and 2 with another motor and wheel. By the end, you should have two wheels, each attached to their own motor.

The front two wheels do not have to be attached to the motor. They simply have to move.

1. Take a metal axle of 27 cm and apply an attachable wheel on both sides. Make sure they fit properly.
2. After, take out the wheels. Apply hot glue on the ends of one side of the axle and re-attach ONE wheel so it is attached firmly.

Find a cardboard box (the body of the rat)

1. The box should have the following dimensions: 6x11x12 inches. Make sure there are no holes and/or cracks on it.
2. The top of the box, with dimensions 11x12 should be open. If not, use a box cutter to cut it out

Back Holes

The wheels in the back will be attached to motors that will drive the rat forward. To do this, we need to make holes so that the motor and wheel can be attached to the body of the vehicle

1. Using a marker, create a dot 6.5 cm horizontally from the edge of one side and 1 cm up vertical from the bottom of the cardboard box.
2. Take the smaller end of the D.C motor, and press the center of it on the marker spot.
3. Trace the circumference of the D.C motor on the box
4. Move on to a cutting board, and cut open the circle you made with the D.C motor and marker, using a box cutter.
5. Now, enter the smaller end of the D.C motor into the hole. It should fit in with some difficulty, so that it doesn't fall out but also isn’t too small.
6. Repeat steps 1-5 on the opposite side of the cardboard box. You should now have two big circular holes. These will become your motors for the rat.

Reminder: After making sure the motors fit in the hole well, take it out. We will be attaching it on later.

Front Holes

We now need to make holes for the front wheels. This step will be similar to the previous one. These holes will be a lot smaller than the back holes as the wheels going in these holes are not attached to motors.

1. Using a marker, create a dot 6.5 cm horizontally from the edge of the same side used to create the front back motors, and 1 cm up vertical from the bottom of the cardboard box.
2. previously, we took a metal rod and attached it to a wheel. Grab this and line it up right over the hole.
3. Trace the circumference of the axel rod on the box using a marker
4. Move on to a cutting board, and cut open the circle you made with the metal rod and marker, using a box cutter.
5. Now, enter the smaller end of the metal rod into the hole. It should fit in with some difficulty, so that it doesn't fall out but also isn’t too small.
6. Repeat steps 1-5 on the opposite side of the cardboard box. You should now have two tiny holes that will eventually have wheels sticking out of them

Reminder: After making sure the motors fit in the hole well, take it out. We will be attaching it on later.

In this step, we will be attaching brown fur onto the cardboard box, in order to give the rat some realistic features.

Cutting and attaching pieces of fur

We want to cover all sides of the cardboard box (albeit the top) with this fur.

1. On a tape, stretch the 40x32 cm fur out.
2. Flip it so that the side that doesn’t have fur on it is facing up
3. Since two of the cardboard boxes’s dimensions are 6x11, we will need to cut out two rectangles of fur with the same dimensions so that it covers the respective sides of the box completely
4. Using a ruler and marker, measure 6 inches up on the box, and 11 in horizontally. Create a rectangle
5. Take scissors and cut on the marked spots.
6. The cardboard box also has two sides with dimensions 6 x 13 inches. Repeat steps 3 and 4 and create a piece of fur with dimensions 6x13 inches.
7. Repeat steps 3 till 5 once again, until you have two rectangle pieces of fur with the dimensions 6x11 and 6x13 inches.
8. Since there is only one side with dimensions 11x13, repeat steps 3 and 4 only once with these dimensions.
9. Using a superglue gun, attach all these pieces of fur onto the cardboard box. The cardboard box should no longer be visible (other than the top)

Creating holes in fur pieces

We need to create holes in the fur pieces so that the motors and wheels can go through the body. We only need to make these holes on the 6x13 inches cardboard box sides.

1. The top of the cardboard box is open. Look in.
2. You will notice the holes that you had previously made in the cardboard box on the two sides. However, the fur is completely covering the holes.
3. Using a marker, trace the same dimensions of the hole that you made on the cardboard box on the fur.
4. Cut out this hole using scissors.
5. Repeat steps 3 and 4 for all 4 holes. Now you should have a cardboard box that has fur attached on to it, with holes in 4 places that allow for motors to stick through them.

In order for us to power the motors, we need to have batteries somewhere on the rat. To do this, lets create an engine spot on the back side of the body.

1. Cut out dimensions 5x12 inches on this cloth.
2. Using superglue, glue this fabric onto the side of the box that is right behind the big motor holes.
3. Get two fully charged 9V batteries.
4. With the power side facing up, glue them onto the fabric. They should be equally distanced from one another

Note: While the image above does not have any fur on it, yours should. Other than that however, your model should be identical to the diagram above.

Attaching the back motors

1. Take the motor with the wheel attached on it and stick it into the back hole. It should be stable, but if not, put some hot glue around it and then stick it in.
2. Repeat step 1 on the other side of the box.
3. Now, take the metal rod that has one wheel attached to it, and stick it in into the hole that it was made for on the front of the box. Once in and stable, grab another wheel of the same size and glue it onto the other end of the stick. The front wheels should now be completely attached onto the body of the rat.

Powering the back motors

In order for the rat to move, the motors need to spin the wheel, and in order for this to happen, they need to be connected to batteries.

1. Take a green alligator clip and a white alligator clip.
2. From the inside, clip them onto the studs sticking out of the motor. On the opposite side of the clips, take the wire over the top of the box, and attach the green alligator clip to the negative end of the battery, and the white clip to the positive end of the batter.
3. Repeat steps 1 and 2 for the other motor and battery

Shape of The Head

1. Get a one dimensional cardboard piece.
2. Cut out the shape of the rat face (as seen in the picture above) on the cardboard box

The Eyes

1. Using cardboard, create two circular shapes with a diameter of 4 cm.
2. Cut them out using a box cutter
3. Color them black completely using acrylic paint
4. Glue them onto the face of the rat. Make sure they are equidistant from one another.

The Nose

1. Cut out three pieces of cardboard. One should be a rectangle with dimensions 5x4 inches. The other two should be triangles.
2. Glue the triangular cardboard pieces onto the face. The lower end should start between the eyes, and it should get bigger and bigger.
3. Attach the two triangular pieces by adding the rectangular cardboard piece on top. Superglue them together.
4. Cut out some fur and glue it over the cardboard so that it can't be seen anymore

Attaching head to the body of rat

1. Super Glue the bottom half of the back of the face, and attach it onto the front side of the rat body.

1. Take a bunch of black pipe cleaners. Stick one end to the back side of the rat body (right above the batteries) by taping it.
2. Twirl the other ends in all sorts of ways. (up to you how you want the rat tail to look like)

1. Take fur and drape it over the open side of the rat. Glue the ends down, however it should still be openable if the user needs to make adjustments to the insides of the rat.

There you have it! That was so simple, and now you have a killing machine in your possession! Enjoy your halloween as you go around scaring your friends and family with your very own, customized rat!