# Title Team Members TA Documents Sponsor
37 Wireless Laptop Charging System
Enrique Ramirez
Jason Kao
Onur Cam
Zhen Qin design_review
With the advent of wireless charging products for low-powered devices (phones, tablets etc.), we wonder if we could charge higher powered devices like laptops, by combining them. Laptops in class are very common due to their note taking efficiency. However, economical laptops preferred by students have low battery life, which causes them to rely on their chargers. The prevalence of these laptops causes an excessive amount of cable traffic. We believe that our project will help regulate cable traffic and thus create a more organized classroom.

What makes our project unique is that we are expanding on the concept of wireless inductive charging by connecting multiple low power wireless receiver to create a wireless adapter that plugs in to your laptop's power jack.

Based on our research, there is only one product on the market made by Dell, which retails for $200 and only works with one laptop also produced by Dell. Their laptop has an internal inductive charging receiver, and a transmitter pad.

In our project, we are trading convenience for universality; instead of requiring the purchase of a new laptop for access to wireless charging, you would only need to buy the external adapter and the corresponding transmitter. Our product will target two different markets: academic organizations and individuals. The Qi 1.1 transmitters would be implanted in classroom tables and our receivers will replace the charging blocks.

What we will completely design and build:
4 x Receiver coils
4 x AC to DC Converters -> includes rectifier, filter and regulator circuits.
1 x DC to DC converter-> filter, regulator circuits
1 x Feedback Circuit for DC to DC converter-> includes Error Generator and PI controller

Design thought process:
The charging pad(receiver), will be completely designed by us. It will consist of 4 coils that we will build ourselves.

Our coils will be designed according to the electrical requirements of our AC-DC converter output. The coil should cover at least 75% of the 5W Qi transmitter so that we achieve acceptable efficiency and coupling. By following the WPC(Wireless Power Consortium) standard we will experiment on number of turns and coil dimensions and the gap between them to be able to produce a satisfactory coil that is as small as possible.

Each coil will be connected to its own AC-DC converter. This AC-DC converter will consist a full-wave rectifier, a filter and a regulator to output our goal voltage which is 5V with 5W power. Our 4 AC-DC converters will be serially connected to supply 20V to our self-designed DC-DC converter. This DC-DC converter will step-down the 20V it receives to output 12V and 3.33A DC for powering our laptop.

In order to receive consistent power output from the DC-DC converter, we will implement a feedback system that will regulate the output voltage to the laptop jack. The feedback system will include a error generator, the proportional integral (PI) circuit and a comparator that can change the gate drive input that helps maintain a steady output.

We’ll be powering 4 Qi 1.1 transmitters independently to generate an electromagnetic field for each individual receiver coil, positioned corresponding to our coils in the charger pad. We want our project to be compatible with standard on-the-market transmitters, so we will not be designing the transmitter ourselves.

Our planned design diagram:

Previous rejected RFA:
Idea Discussion:

Product in Market:
Dell Wireless Charging Mat - PM30W17:

Smart Frisbee

Ryan Moser, Blake Yerkes, James Younce

Smart Frisbee

Featured Project

The idea of this project would be to improve upon the 395 project ‘Smart Frisbee’ done by a group that included James Younce. The improvements would be to create a wristband with low power / short range RF capabilities that would be able to transmit a user ID to the frisbee, allowing the frisbee to know what player is holding it. Furthermore, the PCB from the 395 course would be used as a point of reference, but significantly redesigned in order to introduce the transceiver, a high accuracy GPS module, and any other parts that could be modified to decrease power consumption. The frisbee’s current sensors are a GPS module, and an MPU 6050, which houses an accelerometer and gyroscope.

The software of the system on the frisbee would be redesigned and optimized to record various statistics as well as improve gameplay tracking features for teams and individual players. These statistics could be player specific events such as the number of throws, number of catches, longest throw, fastest throw, most goals, etc.

The new hardware would improve the frisbee’s ability to properly moderate gameplay and improve “housekeeping”, such as ensuring that an interception by the other team in the end zone would not be counted as a score. Further improvements would be seen on the software side, as the frisbee in it’s current iteration will score as long as the frisbee was thrown over the endzone, and the only way to eliminate false goals is to press a button within a 10 second window after the goal.