Juan (Candice) Cai：hardware circuits design & implementation. Programmer.
Yuhan (Meredith) Xie：works on house and components building, final report, and video.
The purpose of this project is to design a system that protects a house from zombie or burglar attacks. This system accepts signals form Gateways, triggers the server motors, sound & light sensors to attack the zombies and burglar.
When the Arduino senses the signal of Zombie attack there will be a spinning spoon shooting out chocolate to attack the zombie; when it senses burglar attack, burglar will be defeated by front door and back door trap. The front trap is controlled by a pressure sensor, and the back one is controlled by a DC motor.
People who are troubled by zombie and burglar attack, who needs smart pieces of the house to protect their business.
Design & Implementation Process
Design of this smart cafe can be divided into two parts. The first part is the doll house implementation. We purchased some wooden piece, decoration-used LEDs and wall papers. My teammate Meredith built the whole house from nothing.
The other part is Arduino implementation, which is the part I worked on. I designed the system to be able to receive signals from Gateways and make response to it. It's functionality is to make buzzing noise (buzzer alert), red LED light alert and physical attack, and activates two traps.
In the beginning, I simply implemented one Xbee, LED light, and LCD screen to let the LCD twinkle when receiving a signal and print out the signal to the LCD screen. Then, I started building piezo buzzer into the hub and let it playing an alert when receiving a zombie alert signal by using an if loop. Then I built one servo motor into the hub so that it rotates when the piezo buzzer is making a sound. After that, I built one button to it so that every time users press the button the alert will stop. At this time, I have built in the initial hub with a basic chocolate ball shooter, alert, and lighting.
After that, I added one pressure sensor and one servo motor to the hub as our backdoor trap, and then added one potentiometer sensor and another servo meter as our front door trap. I also added one condition in the if/else loop to make the hub does something when receiving burglary alert. During this time, I changed the code of the alert so that it accepted an array of music notes as a parameter. This made the alert sound of the burglary alert different from the zombie alert.
Success & Delights
The success part of this project is how we managed to blend our trap into the house. Since we build the house and Arduino pieces separately, we thought making the motor servers working on the roof of this house and under that yard would be hard. We managed to make it work after all. That's one of our best success.
Challenges & Despairs
Challenge is definitely the physical part. Hardware implementation turned out to be so much harder than we imagined. After test the Arduino and made sure that this could work, we started to build them together. However, fitting the three Arduino pieces together is so hard. It was also impossible to use the pressure sensors and such when we simply stuck everything in house. We ended up build a small door on the back of the house to fit everything in and control the traps.
Despair stroke on me when I realized the spinning angel of motor server was really hard to control. I used three motor servers to control the spinning spoon and floor traps. I calculated carefully what direction and angel the motor server would go, and finally fixed it.
We totally enjoyed the whole process of making this project. We tried hard and went beyond of our initial requirement of ourselves and challenged ourselves. When we first designed this house, we were going to simply use a paper box and build a small room. However, we ended up building a prettier doll house. On the side of the Arduino, though we are not total expert of using Arduino, we still tried hard and got help from a lot of people. We added different features one by one, and at last pulled them off together.
One thing we learned from this four weeks of building process is: start early, because we iterate the design and implementation process. We built and took them apart and built again. This process made the final product much better.