Project

# Title Team Members TA Documents Sponsor
34 iBand
 Panav Munshi
Rutu Brahmbhatt
Saaniya Kapur
 Hojoon Ryu design_document1.pdf
design_document2.pdf
final_paper1.pdf
presentation1.pdf
proposal1.pdf
# Team Members
- Saaniya Kapur (saaniya2)
- Rutu Brahmbhatt (rub2)
- Panav Munshi (pmunshi2)

# Problem

A group of researchers at UIUC are building a wearable device, known as the iBand, that is similar to the Myo armband and uses different sensors to collect biosignals and kinetic data from the human forearm. This project is funded by the JUMP ARCHES grant and was previously performed by Health Care Engineering System Center. Currently, the device consists of three types of sensors - the IMU, pulse and EMG, all of which are functional. It transmits this data wirelessly via Bluetooth to a computer through a custom-built Python user interface that accompanies the iBand to collect, save, and present the data in real time. This device has multiple possible applications, such as remotely controlling computers, computer gaming, virtual or augmented reality and performance assessment in sports or training.

The device has completed phases 1 and 2 of design and is now in phase 3. The problems encountered in the previous phases are in regards to device sizing, as well as data collection and representation. The project in its current state is lacking a portable power unit, calibrated sensors and an enclosure. The goal of phase 3 is to optimize the hardware and software in order to complete the prototype while keeping costs in mind. The final product must be kept under $300, or at the maximum, under $500.

# Solution Overview

The following three design components/subsystems solve the specified problems surrounding size optimization, the collection of precise and accurate data, and the effectiveness of representing that data to an outside party.

The first design component at a high level includes constructing an armband that will encase various EMG and IMU sensors at areas of the body in which movement is the differentiating factor in regards to what hand gesture is being made.

In order to design this device, we will need to optimize the circuit by downsizing the current design. This will require selecting and replacing components, such as replacing the current microcontroller with a smaller microcontroller or a printed circuit board (PCB).

# Solution Components

- **Subsystem 1:** The first design component concerns the type of sensors that we would use in this design are the ones that have been utilized during the prototyping process of this pitched project. The sensors in question are the IMU (Internal Measurement Unit) which is a sensor that includes a gyroscope and an accelerometer. The accelerometer is used to measure linear acceleration whereas the gyroscope is used to measure angular velocity which when coupled together provides us with an accurate measurement of total hand movement. The other sensor consists of an EMG (Electromyography Sensor) which measures the electrical signals generated from an individual’s muscles moving. There are eight (8) of these in the current design. They are useful in determining and differentiating which muscles the individual is activating while making a specific movement. Lastly, the device includes a pulse sensor which measures heart rate. An additional sensor that we may add to the ones already being used in the first prototype is a Flex Sensor which measures the amount of deflection or bending that is being done on the surface it is hosted on. This will be useful in order to add another layer of accuracy to the position and movement measurements that are introduced through the IMU.

- **Subsystem 2:** The second design component is to downsize the current design in order to ensure it is an armband. This will entail multiple changes. The first will be to select or build a power source that is portable and meets the necessary voltage and current ratings. The next will be to replace the microcontroller with a PCB or a different microcontroller that is small enough to be incorporated into the wearable while maintaining high efficiency. Following this, it may be necessary to modify the placement of the sensors in order to optimize the circuit.

- **Subsystem 3:** The third design can be bifurcated into two individual components. The first one being switching from hardware based data filtering to software based filtering. This will turn out to be important as being able to do so will allow us to remove several components from the base PCB, reducing the package size. The next component is developing a frontend UI for the entire device. This will allow us to reprogram configuration values, monitor data from sensors, and so on.

Criterion for Success
The project, as described by Hajar and other leads, is currently in Phase 3 and requires the completion of milestones. Therefore, the completion of said milestones can be viewed as the criterion for success for this senior design project.

The following are the milestones detailed by the team leads:
- Installing new sensors; calibrating newly and previously installed sensors.
- Enabling synchronous data collection from both new and existing sensors.
- Building a power source for the device and an enclosing.
- Downsizing the package of the device and optimizing sensor placement.
- Investigating the use of a different microcontroller with the intention to reduce the size of the device.
- Desoldering and resoldering wires and other device components.

New sensors, once evaluated for their efficacy in regards to the use case, can be installed into the device package. Examples of such sensors include a Flex Sensor, as described earlier.

Calibrating sensors will include normalizing the collected sensor data against verified data that can be obtained from other sources, such as research studies, publicly available repositories, and so on.

Data collection from the sensors should occur in parallel in order to make sure there exists separate datastreams for each of the sensors. This will be achieved by utilizing multithreading, with each sensor group having its own dedicated thread.

A robust power supply needs to be designed in order to meet the design needs of the device - the device needs to be designed in such a way that it functions as a wearable. This will be done by designing a PCB that will host the power unit.

As the current device setup consists of individual components connected to the main board separately, it is imperative to create or utilize a housing that will incorporate all the sensors and the power unit. Additionally, it might be necessary to explore the use of other microcontrollers if design and size constraints of the housing are not met. Potential options include STM32 microcontrollers, and so on. All this will have to be done while keeping cost in mind; the total cost of the final product must be between $300-$500.

Prosthetic Control Board

Caleb Albers, Daniel Lee

Prosthetic Control Board

Featured Project

Psyonic is a local start-up that has been working on a prosthetic arm with an impressive set of features as well as being affordable. The current iteration of the main hand board is functional, but has limitations in computational power as well as scalability. In lieu of this, Psyonic wishes to switch to a production-ready chip that is an improvement on the current micro controller by utilizing a more modern architecture. During this change a few new features would be added that would improve safety, allow for easier debugging, and fix some issues present in the current implementation. The board is also slated to communicate with several other boards found in the hand. Additionally we are looking at the possibility of improving the longevity of the product with methods such as conformal coating and potting.

Core Functionality:

Replace microcontroller, change connectors, and code software to send control signals to the motor drivers

Tier 1 functions:

Add additional communication interfaces (I2C), and add temperature sensor.

Tier 2 functions:

Setup framework for communication between other boards, and improve board longevity.

Overview of proposed changes by affected area:

Microcontroller/Architecture Change:

Teensy -> Production-ready chip (most likely ARM based, i.e. STM32 family of processors)

Board:

support new microcontroller, adding additional communication interfaces (I2C), change to more robust connector. (will need to design pcb for both main control as well as finger sensors)

Sensor:

Addition of a temperature sensor to provide temperature feedback to the microcontroller.

Software:

change from Arduino IDE to new toolchain. (ARM has various base libraries such as mbed and can be configured for use with eclipse to act as IDE) Lay out framework to allow communication from other boards found in other parts of the arm.