Project

# Title Team Members TA Documents Sponsor
36 Anti-Lock Braking for Bicycles
Aidan Rodgers
Ethan Chastain
Leon Ku
Nithin Balaji Shanthini Praveena Purushothaman design_document4.pdf
final_paper2.pdf
other1.jpeg
photo1.jpeg
presentation1.pptx
proposal2.pdf
video
Anti-Lock Braking for Bicycles

Team Members:
- Ethan Chastain (ecc5)
- Aidan Rodgers (aidanfr2)
- Leon Ku (leonku2)

# Problem

Bicycles present a challenge because they often lack or charge a premium for the features that cars have, like Anti-Lock Braking Systems (ABS). This happens because bicycles are primarily designed for short distance commuting. Unlike cars that come with a range of amenities, bicycles prioritize simplicity. However, this difference in design leads to a discrepancy in safety and convenience features. Bicycle riders do not have the braking capabilities and automated speed regulation that many cars offer. This absence of features like ABS can be particularly dangerous as bicycles are prone to skidding; thus increasing the risk of accidents. As mobility solutions, bicycles sacrifice these functionalities, which means riders must navigate roads with heightened awareness and limited technological assistance.

# Solution

In order to improve the safety of bicycles via cheaper, preventative features, we could consider adding technologies commonly used in cars. For instance, adding an Anti-lock Braking System (ABS) would reduce the risk of skidding by braking more efficiently; thereby improving overall safety. More importantly, the use of ABS ensures better stability for riders and helps prevent accidents like collisions at an intersection. By embracing these technologies, bicycles can offer riders safer, cheaper rides with improved ease of use. We plan to use one of the bikes provided by the workshop and add a braking system that both detects locking and modulates braking to account for it.

# Solution Components

## Subsystem 1 - Speed sensing

We plan to use a Hall effect sensor (potential part number: DRV5023BIQLPGMQ1) to sense rotational motion of the bicycle’s rear wheel, to determine the speed of the bicycle. This will interface directly with the microcontroller to allow for the braking system to pulse the brakes if locking occurs. The sensor will also be used to record data, in order to test for proper operation.

## Subsystem 2 - Braking

This system takes inputs from the microprocessor to operate the brakes of the bicycle. The braking subsystem consists of a servo motor and a gear system to mechanically pull the brake cable, upon input from the microprocessor. As this system will interfere with the normal mechanical braking system of the bicycle, we will implement buttons in place of the typical brake controls on the handlebars, which will interface with the microprocessor to allow for the bicycle to brake.

## Subsystem 3 - Microprocessor

The microprocessor subsystem will take information from the Hall effect sensors about the rotational speed of the bicycle’s wheel. This subsystem will use an ATMega controller to implement the control algorithms. We plan to use LQR or PID control as a means of tracking constant slopes to prevent wheel locking when decelerating. By this method, we will be able to flash a controller onto the microcontroller in order to embed our control on the PCB.

# Criterion For Success

To qualitatively test the bicycle’s anti-lock braking mechanism, we will place the bicycle on a treadmill and slam the brakes, to observe visually the bicycle’s braking operation. During this test, data from the Hall effect sensor relating to the speed of the bicycle’s rear wheel will be recorded during the test, demonstrating that the bicycle is slowing down properly and efficiently.


Electronic Mouse (Cat Toy)

Jack Casey, Chuangy Zhang, Yingyu Zhang

Electronic Mouse (Cat Toy)

Featured Project

# 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

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