Project

# Title Team Members TA Documents Sponsor
2 Seeing Ⓘ Hat
Matthew Esses
Mitchell Gilmer
Shreya Venkat
Sanjana Pingali design_document1.pdf
design_document2.pdf
final_paper1.pdf
presentation1.pptx
proposal1.pdf
# Seeing Ⓘ Hat
Team Members
Shreya Venkat (shreyav3)

Mitchell Kalogridis Elekzandros Varik Gilmer (gilmer2)

Matthew Esses (messes2)

# PROBLEM
Individuals with visual impairments encounter difficulties in independent navigation of their surroundings, causing lowered spatial awareness and concern with their personal safety.While there are solutions such as canes or seeing eye dogs, there is an issue with detecting range for objects further than a meter out. Seeing eye dogs only take the owner into a certain direction and are used to make sure the user stays in a straight line from their directions. Dogs can unfortunately become distracted by things like food or children petting the, even with training. Also, there are likely people allergic to dogs or with traumatic experiences that wouldn't want one, while the dog requires being taken care of constantly as a pet.


# SOLUTION
We want to make a hat designed to empower blind individuals by offering a 360-degree field of view. It will use advanced LiDAR sensors for wayfinding and dead reckoning, and Doppler RADARs for collision detection. This technology translates the surrounding environment into real-time spatial data, allowing users to navigate their surroundings with newfound independence. The hat also includes vibration motors strategically placed to indicate the direction of the nearest objects, aiding users in easily navigating their environment.
# SOLUTION COMPONENTS

# Subsystem 0: Microcontroller processing unit
- **STM32F401:** Microcontroller with 11 PWM outputs, massive processing power
## SUBSYSTEM 1: IMAGING AND SENSING SYSTEM
This subsystem focuses on capturing real-time spatial data
- **LIDAR SENSOR USING I2C:** Primary imaging sensor for user dead reckoning
- **Accelerometer and magnetometer** Tracking and adjusting user movement for data calculations
- **HB100 Doppler RADAR:** Secondary emergency collision detection sensor
- **Small LCD screen:** Diagnostic tool (not for user, this is for debugging)
## SUBSYSTEM 2: SCANNING MECHANISM
This subsystem focuses on the rotation of the scanner and the associated motor control.
- **Motor Driver:** Controlling rotational speed of the scanner using PWM input from the microcontroller
- **DC Brushless Motor** Main mechanical power source
- **Hall Effect Sensor Circuit:** For determining the direct angular positioning of a motor
- **3D printed parts and slip ring:** Mechanical backbone of project for properly transferring rotation to the LiDAR
## SUBSYSTEM 3: HAPTIC FEEDBACK SYSTEM
This subsystem includes vibration motors for providing haptic feedback to the user.
- **Demultiplexers/Decoders:** These receive output from the STM32 and outputs a PWM signal from the microcontroller to the vibration motors.
- **16 Vibration Motors:** Place vibration motors at various angles within the hat to indicate the direction of the nearest objects. In a power of 2 to mesh with the demultiplexers..
# SUBSYSTEM 4: Battery Power Supply Subsystem:
Create boost/buck converter circuits for power supplies to ensure uniform voltage supply.
- **LiPO batteries** - May be 3.7V in series - lightest reasonable weight, small form factor power source
- **Battery holder:** Holding the battery
- **eFuse current limiter, undercurrent included:** Safety sensor for microcontroller and components for rapid shut off
- **Over/Undervoltage lockout:** Safety sensor for components for rapid shut off
- **Buck converter:** Stepping down voltage for microcontroller and sensors
### A buck converter may or may not be required depending on the final motors and microprocessors. The microprocessor is rated for 3.75 - 5.2V. Our preferred method of accomplishing this voltage step down would be a buck converter. The in-line non-switching solutions appear to not be viable with the current draw requirements.
### The microprocessors range is close to the battery pack range. Depending on the final system requirement, the system may be viable to operate on a singular IC provided by Texas Instruments.
### If the buck converter is not an IC, then we would need to build a buck converter using a buck controller.
# CRITERION FOR SUCCESS
1) The Hall Effect sensor, magnetometer, and accelerometer are able to provide accurate heading and sensor data for the haptic feedback within 45 degrees accuracy when displaced.
2) Able to image a room, such as ECEB 2072, from the center at resolution of at least 0.2 meters using haptic feedback and with a monitor for others’ viewing as a diagnostic tool with a 360 degree range with an angular resolution and accuracy of 15 degrees.
3) Able to detect objects approaching the user from front, back, below, and both sides within 2 seconds using both the Doppler proximity sensor and the LIDAR.
4) Navigational Success: The Hat successfully aids a blindfolded user in navigating the second and third floors of ECEB without difficulties.
5) Power Supply Stability: Power system safely shuts down during extreme conditions such as battery failure and short circuit conditions without damaging the hardware.

Control System and User Interface for Hydraulic Bike

Iain Brearton

Featured Project

Parker-Hannifin, a fluid power systems company, hosts an annual competition for the design of a chainless bicycle. A MechSE senior design team of mechanical engineers have created a hydraulic circuit with electromechanical valves, but need a control system, user interface, and electrical power for their system. The user would be able to choose between several operating modes (fluid paths), listed at the end.

My solution to this problem is a custom-designed control system and user interface. Based on sensor feedback and user inputs, the system would change operating modes (fluid paths). Additionally, the system could be improved to suggest the best operating mode by implementing a PI or PID controller. The system would not change modes without user interaction due to safety - previous years' bicycles have gone faster than 20mph.

Previous approaches to this problem have usually not included an electrical engineer. As a result, several teams have historically used commercially-available systems such as Parker's IQAN system (link below) or discrete logic due to a lack of technical knowledge (link below). Apart from these two examples, very little public documentation exists on the electrical control systems used by previous competitors, but I believe that designing a control system and user interface from scratch will be a unique and new approach to controlling the hydraulic system.

I am aiming for a 1-person team as there are 6 MechSE counterparts. I emailed Professor Carney on 10/3/14 and he thought the general concept was acceptable.

Operating modes, simplified:

Direct drive (rider's pedaling power goes directly to hydraulic motor)

Coasting (no power input, motor input and output "shorted")

Charge accumulators (store energy in expanding rubber balloons)

Discharge accumulators (use stored energy to supply power to motor)

Regenerative braking (use motor energy to charge accumulators)

Download Competition Specs: https://uofi.box.com/shared/static/gst4s78tcdmfnwpjmf9hkvuzlu8jf771.pdf

Team using IQAN system (top right corner): https://engineering.purdue.edu/ABE/InfoFor/CurrentStudents/SeniorProjects/2012/GeskeLamneckSparenbergEtAl

Team using discrete logic (page 19): http://deepblue.lib.umich.edu/bitstream/handle/2027.42/86206/ME450?sequence=1