Project

# Title Team Members TA Documents Sponsor
50 Electronic Mouse (Cat Toy)
Honorable Mention
 Chuangy Zhang
Jack Casey
Yingyu Zhang
 Jamie Xu design_document1.pdf
final_paper1.pdf
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photo1.jpeg
presentation1.pdf
proposal1.pdf
video
# Electronic Mouse (Cat Toy)

# Team Members:
- Yingyu Zhang (yzhan290)
- Chuangy Zhang (czhan30)
- Jack (John) Casey (jpcasey2)

# Problem Components:
Keeping up with the high energy drive of some cats can often be overwhelming for owners who often choose these pets because of their low maintenance compared to other animals. There is an increasing number of cats being used for service and emotional support animals, and with this, there is a need for an interactive cat toy with greater accessibility.
1. Get cats the enrichment they need
1. Get cats to chase the “mouse” around
1. Get cats fascinated by the “mouse”
1. Keep cats busy
1. Fulfill the need for cats’ hunting behaviors
1. Interactive fun between the cat and cat owner
1. Solve the shortcomings of electronic-remote-control-mouses that are out in the market

## Comparison with existing products
- Hexbug Mouse Robotic Cat Toy: Battery endurance is very low; For hard floors only
- GiGwi Interactive Cat Toy Mouse: Does not work on the carpet; Not sensitive to cat touch; Battery endurance is very low; Can't control remotely



# Solution
A remote-controlled cat toy is a solution that allows more cat owners to get interactive playtime with their pets. With our design, there will be no need to get low to the ground to adjust it often as it will go over most floor surfaces and in any direction with help from a strong motor and servos that won’t break from wall or cat impact. To prevent damage to household objects it will have IR sensors and accelerometers for use in self-driving modes. The toy will be run and powered by a Bluetooth microcontroller and a strong rechargeable battery to ensure playtime for hours.
## Subsystem 1 - Infrared(IR) Sensors & Accelerometer sensor
- IR sensors work with radar technology and they both emit and receive Infrared radiation. This kind of sensor has been used widely to detect nearby objects. We will use the IR sensors to detect if the mouse is surrounded by any obstacles.
- An accelerometer sensor measures the acceleration of any object in its rest frame. This kind of sensor has been used widely to capture the intensity of physical activities. We will use this sensor to detect if cats are playing with the mouse.


## Subsystem 2 - Microcontroller(ESP32)
- ESP32 is a dual-core microcontroller with integrated Wi-Fi and Bluetooth. This MCU has 520 KB of SRAM, 34 programmable GPIOs, 802.11 Wi-Fi, Bluetooth v4.2, and much more. This powerful microcontroller enables us to develop more powerful software and hardware and provides a lot of flexibility compared to ATMegaxxx.

Components(TBD):
- Product: [https://www.digikey.com/en/products/detail/espressif-systems/ESP32-WROOM-32/8544298](url)
- Datasheet: [http://esp32.net](url)

## Subsystem 3 - App
- We will develop an App that can remotely control the mouse.
1. Control the mouse to either move forward, backward, left, or right.
1. Turn on / off / flashing the LED eyes of the mouse
1. keep the cat owner informed about the battery level of the mouse
1. Change “modes”: (a). keep running randomly without stopping; (b). the cat activates the mouse; (c). runs in cycles(runs, stops, runs, stops…) intermittently (mouse hesitates to get cat’s curiosity up); (d). Turn OFF (completely)

## Subsystem 4 - Motors and Servo
- To enable maneuverability in all directions, we are planning to use 1 servo and 2 motors to drive the robotic mouse. The servo is used to control the direction of the mouse. Wheels will be directly mounted onto motors via hubs.

Components(TBD):
- Metal Gear Motors: [https://www.adafruit.com/product/3802](url)

- L9110H H-Bridge Motor Driver: [https://www.adafruit.com/product/4489](url)

## Subsystem 5 - Power Management
- We are planning to use a high capacity (5 Ah - 10 Ah), 3.7 volts lithium polymer battery to enable the long-last usage of the robotic mouse. Also, we are using the USB lithium polymer ion charging circuit to charge the battery.

Components(TBD):
- Lithium Polymer Ion Battery: [https://www.adafruit.com/product/5035](url)
- USB Lithium Polymer Ion Charger: [https://www.adafruit.com/product/259](url)


# Criterion for Success
1. Can go on tile, wood, AND carpet and alternate
1. Has a charge that lasts more than 10 min
1. Is maneuverable in all directions(not just forward and backward)
1. Can be controlled via remote (App)
1. Has a “cat-attractor”(feathers, string, ribbon, inner catnip, etc.) either attached to it or drags it behind (attractive appearance for cats)
1. Retains signal for at least 15 ft away
1. Eyes flash
1. Goes dormant when caught/touched by the cats (or when it bumps into something), reactivates (and changes direction) after a certain amount of time
1. all the “modes” worked as intended

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.