Project

# Title Team Members TA Documents Sponsor
3 Bicycle Automated Turn Signal (BATSignal)
 Bora Cukurova
Hanna Zayed
Natalya Bapst
 Zipeng Wang design_document0.pdf
final_paper0.pdf
presentation0.pptx
proposal0.pdf
Problem: Cyclists often are required to use their hands to indicate when they are about to make a turn. This is often difficult and dangerous, especially when biking at nighttime. Several products exist on the market for bicycle turn signals, however all of these products force the cyclist to have to move their hands off of their handlebars to indicate a turn. The current products on the market require the cyclist to have to use a control box located in between the handlebars. This is dangerous for the cyclist to be looking at the controls as opposed to the road.

Solution: We propose to build a microcontroller based wireless, likely Bluetooth, turn signal that can be mounted on a bike and controlled via switches on the handlebars, with a right turn signal located on the rightmost handlebar and a left turn signal located on the left handlebar. Flashing LEDs will be mounted on the back of the bike to indicate whether the cyclist is turning left or right. We will also use an accelerometer to indicate braking and show this on the LEDs in the back. Furthermore, no products currently on the market have a feature in which the signal deactivates after the turn has been completed. We also propose to use LEDs on the handlebars for alerting the cyclist that the turn signal has been successfully deactivated. We will power this device using a simple 9V battery.

Team:

Natalya Mila Bapst (bapst2)
Hanna John Zayed (jhzayed2)
Bora Refik Cukurova (cukurov2)

HARMONEX

Rubin Du, Alan Lu, David Song

HARMONEX

Featured Project

**Team**

Alan Lu -- jialin8

Rubin Du -- rd25

**Problem**

Lifting and carrying heavy objects is a common but physically demanding task faced in both personal and industrial environments. Whether it is a person at home carrying groceries or a logistics worker handling cargo, repetitive lifting puts stress on the musculoskeletal system and can result in fatigue, reduced productivity, and even long-term injuries. Existing exoskeleton solutions often focus on industrial use, but they suffer from limited backdrivability, high weight, or overly complex designs that prevent practical everyday use. A lightweight, safe, and efficient solution is needed to reduce the physical burden of lifting while maintaining user freedom of movement.

**Solution**

Our team proposes the development of a wearable exoskeleton system designed to assist users in lifting objects of up to 10 kilograms with minimal effort. The system employs a hybrid actuation strategy that combines the strengths of both a BLDC motor and a servo motor: the BLDC provides the torque required for large-angle lifting motions, while the servo supplies stable holding torque to maintain the lifted position without excess energy drain. The BLDC goes through a 64:1 planetary gear set to amplify torque, and the servo motor goes through a moveable linkage system to create sufficient mechanical advantage to further reduce the load on the motor. A detachable drivetrain allows the user to disengage the actuation system, enabling free arm movement when lifting support is not required. The skeleton itself is lightweight, manufactured using carbon-fiber-reinforced nylon (PA-CF), ensuring durability and comfort. This modular design starts with elbow actuation and can be scaled to include shoulder actuation, broadening its application.

**Solution Components**

**Subsystem 1: Mechanical Skeleton and Drivetrain**

- Lightweight PA-CF composite structure, under 3 kg excluding the battery.

- Hybrid drivetrain using BLDC with planetary gear for motion and servo motor for holding.

- Drivetrain disengagement mechanism for free arm movement.

- Moveable armor integrated with a linkage system on the drivetrain that elaborately moves upper limb armor to avoid structural interference.

**Subsystem 2: Actuation and Power System**

- Actuated by BLDC + servo combination for efficiency and safety.

- Powered by a 6S LiPo battery (~200 Wh), providing several hours of continuous assistance.

- Custom PCB with DC-DC buck converters for peripheral loads and power distribution.

- Thermal management through ventilation and optional forced convection.

**Subsystem 3: Control and Signal Processing**

- Joint actuation regulated through PID controllers.

- User intent detected via EMG sensors integrated into the arm.

- Signal conditioning pipeline: Kalman filter → Chebyshev low-pass filter → controller input.

- Optional manual override via a simple forearm-mounted control panel.

- Microcontroller and peripheral signals integrated on a customized PCB/FPGA.

**Subsystem 4: Peripherals**

- Armor ambient light will be integrated into the shell of the skeleton for aesthetics.

- Ventilation port openings will be controlled by microservos to ensure good heat dissipation.

- A manual control panel will be placed on the lower limb skeleton to include manual operations and emergency switches.

- TPU-based soft pads inside the skeleton to provide a comfort experience for the user.

**Scalability and Modularity**

- The initial prototype targets elbow actuation.

- Design is scalable to include shoulder actuation grounded to chest armor.

- The modular approach ensures meaningful demonstration even if full-body integration is not achieved.

**Criterion for Success**

The final solution will be a wearable exoskeleton capable of assisting the user in lifting and holding objects up to 10 kg through a dual-actuation BLDC–servo system with a detachable drivetrain for free arm movement, powered by an onboard 6S battery, lightweight (under 3 kg excluding the battery), and controlled via EMG signals or a manual override panel to ensure safe, efficient, and natural operation.