Project

# Title Team Members TA Documents Sponsor
52 STRE&M: Automated Urinalysis (Pitched Project)
Adrian Jimenez
Gage Gulley
Yichi Zhang
Abhisheka Mathur Sekar design_document1.pdf
final_paper1.pdf
photo1.jpg
photo2.jpg
presentation1.pptx
proposal2.pdf
video
Team Members:
- Gage Gulley (ggulley2)
- Adrian Jimenez (adrianj2)
- Yichi Zhang (yichi7)

The STRE&M: Automated Urinalysis project was pitched by Mukul Govande and Ryan Monjazeb in conjunction with the Carle Illinois College of Medicine.

#Problem:
Urine tests are critical tools used in medicine to detect and manage chronic diseases. These tests are often over the span of 24 hours and require a patient to collect their own sample and return it to a lab. With this inconvenience in current procedures, many patients do not get tested often, which makes it difficult for care providers to catch illnesses quickly.

The tedious process of going to a lab for urinalysis creates a demand for an “all-in-one” automated system capable of performing this urinalysis, and this is where the STRE&M device comes in. The current prototype is capable of collecting a sample and pushing it to a viewing window. However, once it gets to the viewing window there is currently not an automated way to analyze the sample without manually looking through a microscope, which greatly reduces throughput. Our challenge is to find a way to automate the data collection from a sample and provide an interface for a medical professional to view the results.

# Solution
Our solution is to build an imaging system with integrated microscopy and absorption spectroscopy that is capable of transferring the captured images to a server. When the sample is collected through the initial prototype our device will magnify and capture the sample as well as utilize an absorbance sensor to identify and quantify the casts, bacteria, and cells that are in the sample. These images will then be transferred and uploaded to a server for analysis. We will then integrate our device into the existing prototype.

# Solution Components

## Subsystem1 (Light Source)
We will use a light source that can vary its wavelengths from 190-400 nm with a sampling interval of 5 nm to allow for spectroscopy analysis of the urine sample.

## Subsystem2 (Digital Microscope)
This subsystem will consist of a compact microscope with auto-focus, at least 100x magnification, and have a digital shutter trigger.

## Subsystem3 (Absorbance Sensor)
To get the spectroscopy analysis, we also need to have an absorbance sensor to collect the light that passes through the urine sample. Therefore, an absorbance sensor is installed right behind the light source to get the spectrum of the urine sample.

## Subsystem4 (Control Unit)
The control system will consist of a microcontroller. The microcontroller will be able to get data from the microscope and the absorbance sensor and send data to the server. We will also write code for the microcontroller to control the light source. ESP32-S3-WROOM-1 will be used as our microcontroller since it has a built-in WIFI module.

## Subsystem5 (Power system)
The power system is mainly used to power the microcontroller. A 9-V battery will be used to power the microcontroller.

# Criterion For Success

- The overall project can be integrated into the existing STRE&M prototype.
- There should be wireless transfer of images and data to a user-interface (either phone or computer) for interpretation
- The system should be housed in a water-resistant covering with dimensions less than 6 x 4 x 4 inches

ATTITUDE DETERMINATION AND CONTROL MODULE FOR UIUC NANOSATELLITES

Shamith Achanta, Rick Eason, Srikar Nalamalapu

Featured Project

Team Members:

- Rick Eason (reason2)

- Srikar Nalamalapu (svn3)

- Shamith Achanta (shamith2)

# Problem

The Aerospace Engineering department's Laboratory for Advanced Space Systems at Illinois (LASSI) develops nanosatellites for the University of Illinois. Their next-generation satellite architecture is currently in development, however the core bus does not contain an Attitude Determination and Control (ADCS) system.

In order for an ADCS system to be useful to LASSI, the system must be compliant with their modular spacecraft bus architecture.

# Solution

Design, build, and test an IlliniSat-0 spec compliant ADCS module. This requires being able to:

- Sense and process the Earth's weak magnetic field as it passes through the module.

- Sense and process the spacecraft body's <30 dps rotation rate.

- Execute control algorithms to command magnetorquer coil current drivers.

- Drive current through magnetorquer coils.

As well as being compliant to LASSI specification for:

- Mechanical design.

- Electrical power interfaces.

- Serial data interfaces.

- Material properties.

- Serial communications protocol.

# Solution Components

## Sensing

Using the Rohm BM1422AGMV 3-axis magnetometer we can accurately sense 0.042 microTesla per LSB, which gives very good overhead for sensing Earth's field. Furthermore, this sensor is designed for use in wearable electronics as a compass, so it also contains programable low-pass filters. This will reduce MCU processing load.

Using the Bosch BMI270 3-axis gyroscope we can accurately sense rotation rate at between ~16 and ~260 LSB per dps, which gives very good overhead to sense low-rate rotation of the spacecraft body. This sensor also contains a programable low-pass filter, which will help reduce MCU processing load.

Both sensors will communicate over I2C to the MCU.

## Serial Communications

The LASSI spec for this module requires the inclusion of the following serial communications processes:

- CAN-FD

- RS422

- Differential I2C

The CAN-FD interface is provided from the STM-32 MCU through a SN65HVD234-Q1 transceiver. It supports all CAN speeds and is used on all other devices on the CAN bus, providing increased reliability.

The RS422 interface is provided through GPIO from the STM-32 MCU and uses the TI THVD1451 transceiver. RS422 is a twisted-pair differential serial interface that provides high noise rejection and high data rates.

The Differential I2C is provided by a specialized transceiver from NXP, which allows I2C to be used reliably in high-noise and board-to-board situations. The device is the PCA9615.

I2C between the sensors and the MCU is provided by the GPIO on the MCU and does not require a transceiver.

## MCU

The MCU will be an STM32L552, exact variant and package is TBD due to parts availability. This MCU provides significant processing power, good GPIO, and excellent build and development tools. Firmware will be written in either C or Rust, depending on some initial testing.

We have access to debugging and flashing tools that are compatible with this MCU.

## Magnetics Coils and Constant Current Drivers

We are going to wind our own copper wire around coil mandrels to produce magnetorquers that are useful geometries for the device. A 3d printed mandrel will be designed and produced for each of the three coils. We do not believe this to be a significant risk of project failure because the geometries involved are extremely simple and the coil does not need to be extremely precise. Mounting of the coils to the board will be handled by 3d printed clips that we will design. The coils will be soldered into the board through plated through-holes.

Driving the inductors will be the MAX8560 500mA buck converter. This converter allows the MCU to toggle the activity of the individual coils separately through GPIO pins, as well as good soft-start characteristics for the large current draw of the coils.

## Board Design

This project requires significant work in the board layout phase. A 4-layer PCB is anticipated and due to LASSI compliance requirements the board outline, mounting hole placement, part keep-out zones, and a large stack-through connector (Samtec ERM/F-8) are already defined.

Unless constrained by part availability or required for other reasons, all parts will be SMD and will be selected for minimum footprint area.

# Criterion For Success

Success for our project will be broken into several parts:

- Electronics

- Firmware

- Compatibility

Compatibility success is the easiest to test. The device must be compatible with LASSI specifications for IlliniSat-0 modules. This is verifiable through mechanical measurement, board design review, and integration with other test articles.

Firmware success will be determined by meeting the following criteria:

- The capability to initialize, configure, and read accurate data from the IMU sensors. This is a test of I2C interfacing and will be tested using external test equipment in the LASSI lab. (We have approval to use and access to this equipment)

- The capability to control the output states of the magnetorquer coils. This is a test of GPIO interfacing in firmware.

- The capability to move through different control modes, including: IDLE, FAULT, DETUMBLE, SLEW, and TEST. This will be validated through debugger interfacing, as there is no visual indication system on this device to reduce power waste.

- The capability to self-test and to identify faults. This will be validated through debugger interfacing, as there is no visual indication system on this device to reduce power waste.

- The capability to communicate to other modules on the bus over CAN or RS422 using LASSI-compatible serial protocols. This will be validated through the use of external test equipment designed for IlliniSat-0 module testing.

**Note:** the development of the actual detumble and pointing algorithms that will be used in orbital flight fall outside the reasonable scope of electrical engineering as a field. We are explicitly designing this system such that an aerospace engineering team can develop control algorithms and drop them into our firmware stack for use.

Electronics success will be determined through the successful operation of the other criteria, if the board layout is faulty or a part was poorly selected, the system will not work as intended and will fail other tests. Electronics success will also be validated by measuring the current consumption of the device when operating. The device is required not to exceed 2 amps of total current draw from its dedicated power rail at 3.3 volts. This can be verified by observing the benchtop power supply used to run the device in the lab.