Constructing the robot 

Now, to make this robot, we would need a few cardboard cartons. We need to make two parts of it:

• A food dispenser
• A collecting bowl with a force sensor

First, let's see how the dispenser has to be made. You need to follow these steps:

1. Take a medium-sized carton that can carry up to about four and a half pounds of pet food.
2. Then, go ahead and make a small cutout.
3. This cutout should be big enough to dispense food but not so big that a lot of food comes out of it at once.
4. Now, once that is done, you need to make a lid that covers that through-hole.
5. This lid should be slightly bigger than the through-hole itself. 
6. Install the lid over the shaft of the motor.

7. Fix the motor on to the cardboard, as shown in the following diagram. Make sure that the position of the motor should be such that the lid covers the entire through-hole on the cardboard...