Power strips today have practical problems that make them severely inefficient; put in two laptop chargers and suddenly a 6-plug strip can be completely used up. There are some variations on the market that attempt at a more flexible structure, yet those are still restrictive in design, expensive, difficult to mount, and don't respond to specific user needs, such as USB ports or international travel. So we decided to build an efficient and intelligent power strip that has a more flexible design, provides usage information, and responds to wireless control.
What it does
Structurally, the power strip, stripr, is divided into modules that can extend and rotate, giving more room for diverse plug designs. An LCD display shows real time voltages across each module, and this information is also sent to the cloud where it can be analyzed and the results sent wirelessly to the user's computer or phone.
How we built it
The structural parts of the power strip were built by 3D-printing ABS filament, and the modules are connected by adjustable metal rods which house the wires connecting the modules. We then built a circuit connecting an Arduino with a LCD display, the system also serving as a digital multimeter that measures voltage drops. The Arduino then sends the voltage numbers to a computing system where it can be stored as a text file in the cloud.
For the sake of the prototype and due to limitations in size, parts, and time, the Arduino, breadboards, and circuit wiring are attached to the power strip on the outside.
Challenges we ran into
Due to fire hazard regulations, we couldn't actually plug our power strip into a power source, so in order to demonstrate the function of the prototype, we compromised by wiring 9V batteries, with a small rotating camera appliance, internally through the power strip. We recognize that this isn't exactly how our product will function, but due to the challenge of testing, we decided that using a battery driven motor was the best substitute to mimic a real power supply and appliance.
In addition, we faced difficulty in transmitting the voltage data over the WiFi network. While the system properly provides real time voltage values, it was only able to properly send it to a computer using a direct USB connection. After hours of debugging and reconfiguration, we attribute this setback to the security of the University of Chicago's wireless networks, since the WiFi requires additional security information the Arduino cannot provide and it probably also has other firewall and security features that would affect connectivity. Therefore, the current strip only provides real time information on the LCD display.
Accomplishments that we're proud of
We went through an iterative design process to ensure that we had a quality finished product with complex ideas. We were able to embed a microcontroller to make a "smart" power strip, and we were able to minimize the disadvantages of 3D printing in regards to tolerance.
What we learned
Through this project, we learned a lot about the vast abilities and functions of microcontrollers as well as how to develop advanced Arduino programming functions. We discovered better ways to wire circuits and design hardware, paying special attention to structural integrity. We also got a chance to dive into the world of internet connected devices and the analytics one could potentially unveil using it.
What's next for stripr
Our next steps for stripr would be to formally flesh out the modular concept. We would develop detachable modules, which would allow the product to be customized to each customers needs, such as more USB ports or international outlets. Additionally, we would create an application interface to complement the device.