We decided to try something risky with this project. By making our robot a dangerous machine to work with – as in there is a pocketknife attached to it.
After being inspired by Scam School, we decided to facilitate the “Stab the Chosen Card with a Knife” trick with our robot doing the “stabbing” part of the trick.
To begin with, our robot has two motors, one for the rotation of the knife, and one for driving the back wheels. We wanted a robot that would find the spectator’s card under the newspaper and stab it, drag it out of the newspaper, and reveal the chosen card. Some obstacles that we came across were the types of surfaces the robot was able to work on. For example, the robot is not able to perform this trick on a hard surface since it is impossible for the knife to go through the card on a hard surface. A preferred surface is a carpeted floor. Figuring out fractions of a second that the motor on the knife had to rotate was also a challenge for us, since if the knife rotated too much, it would harm itself, and if it didn’t rotate enough, it would not stab the card. We also adjusted the power of the motor of the wheels when moving forward then backwards, to make people think that the robot messed up after going past a certain point of the newspaper, then returns slowly back to the newspaper to locate the card, causing much dramatic suspense. After all the figuring out, the robot is able to perform the trick flawlessly.
After the human magician performs the card force and allows the spectator to spread the cards randomly under the newspaper, our risky adventure will locate the card and stab it, then bring it out for everyone to see!