Get Away: I Am a Shy Fan

Are you prone to perspiration and overheating? Have you ever experienced a hot and humid day and desperately yearned for a refreshing breeze to help cool you down? Picture this: you have discovered this fan that looks as though it will immediately solve your hot and sticky situation. As you approach it with anticipation and eagerness for its soothing, cool airflow, it inexplicably stops the moment you draw near. 

Introducing the Get Away Fan, where your quest for cooling bliss is met with an unexpected twist! Say goodbye to conventional cooling and hello to the interactive, playful Get Away Fan! 

PSA: Approach with caution, as the Get Away Fan may cause further heating, perspiration, frustration etc. Consult a healthcare physician if symptoms persist or worsen.

Everything You Need:

In case you want to recreate the Get Away Fan for yourself, here is what you will need! As well as a visual representation guide is provided above for easier identification of each component.

Components:

1. Arduino Uno x1
2. Ultrasonic Sensor x1
3. High Torque Servo Motor (14kg*cm) x1
4. 2.1mm Barrel Wire x1
5. 2.1mm Barrel Plug to USB x1
6. 12V 2A Switching Power Supply x1
7. 9V 1.2A Power Supply x1
8. Breadboard x1
9. Power Supply Module x1
10. VNH2SP30 Motor Driver x1
11. Metal Gearmotor 37Dx57L mm 12V (DC motor) x1
12. Fan x1
13. 3D Printed Motor Attachment x1
14. Wires

Materials:

1. ⅛” Frosted Plexi-Glass (Laser Bed Size 18" x 32") x1
2. ⅛” Cardboard (Laser Bed Size 18" x 32") x1
3. WeldBond Glue
4. Superglue
5. Sticky Tack
6. Tape

Equipment:

• Computer
• 3D Printer
• Laser Cutter
• Soldering Kit

Software Programs:

• Arduino IDE
• TinkerCad

Circuit Layout

The fritzing diagram above illustrates a simplified version of our "useless fan" project. We recommend you create your own fritzing diagram to test out different components individually to ensure they function correctly before fully committing to the physical process. 

The final version featured an upgraded DC motor, motor driver, and a larger servo motor. Essentially, the project comprises three main components:

1. DC Motor with Fan: The fan is attached to the end of the DC motor, and we control the fan's speed through the motor driver.
2. Ultrasonic Sensor: Positioned underneath the DC motor, the ultrasonic sensor is used to detect the proximity of objects and people. 
3. Servo Motor: The servo motor precisely rotates the fan to different positions based on the information gathered by the ultrasonic sensor.

Prepare the base for laser-cutting by using the provided file below. Materials such as superglue and Weldbond will be needed for assembling the frosted plexiglass and cardboard for the base. We recommend cardboard for the curvature of the base (outer walls) since it is easy to manipulate into a curved surface – scoring indications are all ready in the file to be laser cut. Along with using the frosted plexiglass on the top of the base allows for a clean look (hiding all the glue, imperfections and messy wiring) while still allowing for the inner components to be visible. 

After preparing and cutting all the materials, it is important to centre two circular base plates (25cm and 24.5cm wide plates) between each other and glue them together. Creating the bottom plate of the base, which will act as a support for the walls. Let it dry to secure the position of the two circles.

Use the rectangle (10cm x 79cm) with the scored lines as the walls of the base. Wrap it around the indented circle (scored side inside) to guide the formation of the perfect circular shape for the base. Using regular Welbond is enough to secure a well-supported base. After letting it dry, the majority of the base is ready to hold all of the components inside.

There is also a sketch that outlines what the entire fan should look like and roughly where each component should be placed.

The overall system at the end is placed on the Servo Motor and can rotate the fan smoothly at roughly 180 degrees. However, to achieve that, an interconnected platform needs to be created to hold the whole system together.

Working from the ground up, a rectangular piece (5cm x 4.5 cm)) is initially glued onto one of the existing servo motor attachments that will act as the holding base. Afterwards, in order to create a needed elevation height from the servo itself, several circular wooden pieces 2.5 cm in diameter are stacked on top of each other. This way, Servo Motor will be able to rotate freely without intersecting with the fan blades at high speeds.

Moving onto the next level of our system is the ultrasonic sensor. To track the distance and motion of highly overheated people, an ultrasonic sensor is placed underneath the DC Motor, thus creating this communication between the two components, making our fan as useless as possible. You can use the provided laser cutting file, to prepare the needed elements to construct the piece holding the ultrasonic sensor. Small indents are created in the walls to place the wires connecting the sensor and the Arduino to maintain a clean and organized look. Over the top, we have placed a small rectangular piece (1.5cm x 4.2cm) to act as coverage and stand for the final level.

For the final level of the system, the DC Motor is placed on a small rectangular piece (4cm x 4.2cm) of cardboard and excessively covered by sticky tack from both sides to keep it supported and in one place, absorbing all the vibration from the motor.

To attach the fan to the DC Motor, we have 3D Printed small modules that are directly fitted onto the rotating nozzle of the motor. They are small components that were glued onto the fan itself, allowing for an easy placement of it onto the motor.

Lastly, all of the 3 levels have been attached to each other using super glue. As a result created a unified rotating module, making our useless fan possible. This module is then laced on the acrylic top of the base and secured with some more sticky tack.

In addition, to retain a cleaner look like most fans, hiding the servo motor and connecting wires is something to consider. For example, creating a cylindrical “tube” that covers the inner elements connected to the fan is also provided in the laser-cutting file. It has the same approach as the walls of the base but on a smaller scale. 

Servo Motor: 

1. Red cable to power (Arduino board)
2. Brown cable to the ground (Arduino board)
3. Orange cable to pin 9

HC-SR04 Ultrasonic Distance Sensor:

1. Vcc to power (Arduino board)
2. Trig to pin 12
3. Echo to pin 11
4. Gnd to Ground (Arduino board)

12V (Helical Pinion) DC Motor with VNH2SP30 Motor Driver: 

1. Solder the positive and negative sides to female power cable
2. Connect the 12V power supply to the soldered female power cable
3. Solder cables to Out A and Out B
4. Solder Out A and Out B cable to 12 V DC motor
5. Vcc to power (Arduino board)
6. Grd to ground (Arduino board)
7. INA to pin 2
8. INB to pin 4
9. PWM to pin 3

For all power and ground pins (Arduino board), use a power supply module with a 9V power supply to make power and ground lines on the sides of the breadboard. 

The project involves interfacing hardware with software coded in the Arduino Integrated Development Environment (IDE). Initially, we integrated various libraries and components to set up the foundation of our "useless fan" project. The core algorithm operates as follows: An ultrasonic sensor is employed to measure distances, determined through physical experimentation with the component. These measured distances are then used to adjust the speed of a DC motor—essentially, the fan's speed. As an object or a human hand approaches the ultrasonic sensor, the DC motor's speed decreases progressively until it halts.

Upon a user moving slightly closer, the servo motor's position is altered based on a value generated by a random number generator. This generator uniquely produces a random number, without repetition, that corresponds to a specific angle, as described earlier. Once all possible numbers have been generated and used, the system resets, continuing to cycle through random numbers.

In the end, after the rotating module has been placed on the plexiglass and all the wiring, the breadboard and Arduino have been placed inside the base, the hole in the plexiglass allows for a direct connection between the inside and the outside of the base keeping all the wiring and components organized.

CONGRATULATIONS YOU MADE THE MOST USELESS FAN EVER!

Although the result of the Get Away Fan's result was successful, it did not come without failures and many trials and errors. This is a part of the learning process of transforming practical knowledge into something useless, which is much more difficult than expected. 

One of the biggest challenges we ran into was consistency and creating something that works MOST of the time. Most of the time, it would work and a lot of the other times it did not (especially when filming). This was mainly due to loose wires and messing around with it too much. With some simple tweaks/refinements to the code and tape around the wires, we were able to create a more stable and consistent working fan.

Discovering a way to provide enough power for the fan was surprisingly challenging, as the DC motor required more power than we expected. There were many trials and errors of different power supply modules, configurations, and combinations.

Another issue we went through was burning one of our Arduino. We did not realize it at first and were wondering what the problem was by rerunning the code, connecting and reconnecting wires, switching wires and turning it on and off. Luckily enough, we had an extra Arduino to come to the rescue, and our problem was resolved quickly. 

Future Iteration

In the future, we would love to explore a tracking system that would make our fans even more useless and annoying. We could also add an annoying sound that leaves you more irritated while using the fan, creating a machine that continuously points away from you, no matter where you are in the room.  

Useless Fan in Action

Course: ARC385 Physical Computing at John H. Daniels Faculty of Architecture, Landscape and Design

Credits: Mucteba Core, Nawal Dabbagh, Ivan Makhno, Sandy Nguyen