Project

# Title Team Members TA Documents Sponsor
30 Multi-entertainment Tic Tac Toe Game
 Jiacheng Zhu
Minkang Yang
Nuochen Lyu
 Xinrui Zhu design_document0.pdf
final_paper0.pdf
other0.zip
other0.zip
other0.zip
photo0.png
presentation0.pdf
proposal0.pdf
video
Outline:

We want to build a smart device that can play tic tack toe, like an arcade game, but in electric design. The game offers functions include normal tic tac toe game, retract a false move, restart, human VS AI mode and human VS human mode and other fancy effects to make it more like a game that we have in the video game center.

Hardware Design:

---The board is composed of two parts: a section comprised of 9 blocks of LED/LCD and another section that displays score and rounds. The tic tac toe board is made by 9 8*8 LED/LCD blocks and 8 pressure sensors under each block.

---The pressure sensors will be made by poking two wires into the foam. When human player press on one of the blocks of the board, a current change would be produced by the pressure sensors and the analog signal from the sensor would be sent to an A/D converting circuit. Finally, the microprocessor would receive the digital signal from A/D converting circuit. The microprocessor knows which cell human have selected and then make a decision as a virtual player.

---The chosen block made by the virtual player will be displayed on the corresponding LED/LCD block (noughts or crosses). There would be a logic circuit for controlling each pixel of the LED/LCD blocks too (total: 576 LEDs/LCDs).

The other section for score display and round number will also be made by LED/LCD blocks and controlled by the microprocessor. The extra LED/LCD blocks show words like "Congratulation! You win!", "Start", "Your Turn". Circuit design would be similar to that on the board.

---A power source will provide power for both LED/LCD and sensors. Since we will use only one input voltage, voltage regulators will need to be built.

---Finally, some buttons will be added for functions such as restarting the game and clearing the score. More effects such as celebrating sound would be added in the future to make this more like a game or make this fancier. Our goal is to make an interesting 445 project that can make people feel delighted and enjoyable.

P.S. If we have time, we may add remote play mode, which would require Bluetooth module.

Active Cell Balancing for Solar Vehicle Battery Pack

Tara D'Souza, John Han, Rohan Kamatar

Featured Project

# Problem

Illini Solar Car (ISC) utilizes lithium ion battery packs with 28 series modules of 15 parallel cells each. In order to ensure safe operation, each battery cell must remain in its safe voltage operating range (2.5 - 4.2 V). Currently, all modules charge and discharge simultaneously. If any single module reaches 4.2V while charging, or 2.5V while discharging, the car must stop charging or discharging, respectively. During normal use, it is natural for the modules to become unbalanced. As the pack grows more unbalanced, the capacity of the entire battery pack decreases as it can only charge and discharge to the range of the lowest capacity module. An actively balanced battery box would ensure that we utilize all possible charge during the race, up to 5% more charge based on previous calculations.

# Solution Overview

We will implement active balancing which will redistribute charge in order to fully utilize the capacity of every module. This system will be verified within a test battery box so that it can be incorporated into future solar vehicles.

Solution Components:

- Test Battery Box (Hardware): The test battery box provides an interface to test new battery management circuitry and active balancing.

- Battery Sensors (Hardware): The current battery sensors for ISC do not include hardware necessary for active balancing. The revised PCB will include the active balancing components proposed below while also including voltage and temperature sensing for each cell.

- Active Balancing Circuit (Hardware): The active balancing circuit includes a switching regulator IC, transformers, and the cell voltage monitors.

- BMS Test firmware (Software): The Battery Management System requires new firmware to control and test active balancing.

# Criterion for Success

- Charge can be redistributed from one module to another during discharge and charge, to be demonstrated by collected data of cell voltages over time.

- BMS can control balancing.

- The battery pack should always be kept within safe operating conditions.

- Test battery box provides a safe and usable platform for future tests.