Project

# Title Team Members TA Documents Sponsor
19 Smart Power Routing with MPPT-Based Wind Turbine
 Rong Li
Tiantian Zhong
Zhekai Zheng
 design_document3.pdf
final_paper3.pdf
proposal2.pdf
 Lin Qiu
## Problem Statement

Traditional wind energy systems often face challenges related to suboptimal power extraction, limited adaptability, and inadequate integration with smart grids. Conventional wind power systems usually requires a giant turbine which produces power for the grid. Yet a new trend arises in recent years where a small wind power system is installed on a fisher or on the roof of a villa. Such scenario requires a stable power converter and router to ensure stable power supply, which not only allows the user to use cheap and clean wind energy, but is also able to switch to battery or mains when wind force is too light to drive the turbine or when the turbine is in fault.

## Solution Overview and Components

The proposed solution involves the development and implementation of the system integrated with a MPPT-based wind turbine. This comprehensive solution aims to address the inefficiencies and limitations of traditional wind energy systems by incorporating advanced technologies for optimal power extraction, intelligent management, and seamless integration with smart grids.

Some key components of the solution are as follows:

1. **Wind turbines.** The project plans to use a three-phase asynchronous motor to build a down-scaled wind turbine. The turbine should produce no more than 30 V AC output under normal weather condition with wind speed less than 8 m/s (force 4). (Similar turbine with suitable size (diameter = 1.1 m) for the project appears on Taobao, which has rated output voltage 12 V, maximum power ranges from several hundred watts to kilowatts, and can work safely within wind speed 35 m/s (wind force 6). Link to the turbine)
2. **MMC-Based AC-DC converter.** This unit is expected to provide stable DC output for users. Its controller consists of MCUs and voltage sensors. The converter should be designed using MMC technology and should be able to implement Maximum Power Point Tracking (MPPT).
3. **User interface.** This unit displays real-time current, voltage and power of the system.
4. **Simulated mains.** This is a low-voltage (<30 V) power supply that simulates the mains. It is apparently down-scaled for safety considerations.
5. **Routing system.** This unit should be able to decide which power should be connected to the load, the turbine or the simulated mains.
6. **Safety.** An emergency stop button should be connected to the circuit in order to cut off all power sources and stop the turbine whenever an emergency happens. Control units should be able to cut the power when the system is overload or in fault status. The solution should fit in relevant national or industrial standards.

## Criterion for Success

The design will be tested using various common loads that is used at home. The following criterion should be satisfied to indicate a successful design:

1. **Safety is the first priority**. All safety measures should be working properly.
2. The controller should be able to keep the converter working at the maximum power point.
3. The MMC converter should be able to provide stable output with current and voltage ripple less than $\pm10\%$​​.
4. The controller should switch between power supplies within a short period of time (specific time limit needs to be determined after further research on relevant national standards and other technical documents).

## Distribution of Work

The project can be divided into three modules – the power system, the control system, and the mechanical system.

- The power system deals with everything related to power transmission, include the design of generators and converters.
- The control system provides control signals to the converter, properly routes power to the load, and provide safety measures.
- The mechanical design should put every hardware components organized to form a ready-to-use product, and print necessary instructions and warnings at proper places.

The following is the detailed task division:

- Power system and circuit design: Rong Li & Zhekai Zheng
- Control system and circuit design: Tiantian Zhong & Rong Li
- Mechanical design and manufacturing: Zhekai Zheng
- Purchasing, finance, and other miscellaneous affairs: Tiantian Zhong

Keebot, a humanoid robot performing 3D pose imitation

Zhi Cen, Hao Hu, Xinyi Lai, Kerui Zhu

Featured Project

# Problem Description

Life is movement, but exercising alone is boring. When people are alone, it is hard to motivate themselves to exercise and it is easy to give up. Faced with the unprecedented COVID-19 pandemics, even more people have to do sports alone at home. Inspired by "Keep", a popular fitness app with many video demonstrations, we want to build a humanoid robot "Keebot" which can imitate the movements of the user in real time. Compared to a virtual coach in the video, our Keebot can provide physical company by doing the same exercises as the user, thus making exercising alone at home more interesting.

# Solution Overview

Our solution to the create such a movement imitating robot is to combine both computer vision and robotic design. The user's movement is captured by a fixed and stabilized depth camera. The 3D joint position will be calculated from the camera image with the help of some neural networks and depth information from the camera. The 3D joint position data will be translated into the motor angular rotation information and sent to the robot using Bluetooth. The robot realizes the imitation by controlling the servo motors as commanded. Since the 3D position data and mechanical control are not ideal, we leave out the consideration of keeping robot's balance and the robot's trunk will be fixed to a holder.

# Solution Components

## 3-D Pose Info Translator: from depth camera to 3-D pose info

+ RealSense Depth Camera which can get RGB and depth frames

+ A series of pre-processors such as denoising, normalizing and segmentation to reduce the impact of noise and environment

+ Pre-trained 2-D Human Pose Estimation model to convert the RGB frames to 2-D pose info

+ Combine the 2-D pose info with the depth frames to get the 3-D pose info

## Control system: from model to motors

+ An STM32-based PCB with a Bluetooth module and servo motor drivers

+ A mapping from the 3-D poses and movements to the joint parameters, based on Inverse Kinematics

+ A close-loop control system with PID or State Space Method

+ Generate control signals for the servo motors in each joints

## Mechanical structure: the body of the humanoid robot

+ CAD drawings of the robot’s physical structure, with 14 joints (14 DOF).

+ Simulations with the Robotics System Toolbox in MATLAB to test the stability and feasibility of the movements

+ Assembling the robot with 3D print parts, fasteners and motors

# Criterion of Success

+ 3-D pose info and movements are extracted from the video by RealSense Depth Camera

+ The virtual robot can imitate human's movements in MATLAB simulation

+ The physical robot can imitate human's movements with its limbs while its trunk being fixed