Project

# Title Team Members TA Documents Sponsor
23 Full Movement Gaming Mouse
Drake Bernhard
Michael Bindon
Anthony Caton design_document0.docx
other0.pdf
presentation0.pptx
proposal0.pdf
The project I would like to work on is a computer mouse that allows the thumb of the mouse hand to control a joystick like device. Some similar devices exist but they use a true joystick that has an awkward feel for directions. My focus is on providing better direction feel on the mouse thumb. The mouse will be built largely from scratch by integrating buttons, positioning laser, the joystick, and USB communication all with an FPGA.

The mouse will be powered through USB, the casing will be 3D printed when the product starts coming together more. The current team is 2 electrical engineers.

The joystick is a slider for analog in game left/right movement, the slider on the mouse will be roughly vertical where thumb down is left (or map-able to anything) and thumb up is right. This slider is combined with a rocking switch which has a central position as well as a pushed forward, pushed backward, and ideally pushed 2x forward for 4 digital positions. Likely project will only have 3 positions for simplicity and ease of part selecting.

Potential Parts list for providing rough idea of design:

Slider: Mouser Part # 652-PTA15432010CIB10 , OR 312-2045F-A100K OR 688-RS15H113CA05
USB Jack and cord, for example Mouser # 474-BOB-12700
Rocker switch ideally is of (ON)-OFF-(ON) type, few cadidates also from Mouser. Also have seen several multi (4+) position slider switches, but these seem less desirably for the feel.
FPGA - have not selected however have experience in Vivado with Artix 7 chip from ECE 437 using an Opal Kelly dev board. Not sure what is allowed as has as if it is ok to start with a basic board and integrate another board of our own design into the project. One possible https://www.xilinx.com/products/boards-and-kits/1-f3zdrn.html
Otherwise my requirements for the FPGA are probably not to difficult. Able to receive a few discrete signals from the rocker switch as well as an analog value from the slider. Will need to confirm voltage levels with the slider are compatable with FPGA. Also FPGA will need to be at lease USB 2.0 capable (as far as speed).
Optical sensing for mouse can be done from scratch or preferably with a board such as https://www.tindie.com/products/jkicklighter/adns-9800-laser-motion-sensor/ where all that is needed is SPI communication to FPGA.

-Drake

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.