Projects

Agentic Distributed System Overload Mitigation

Order Lab @ UMich · Advised by Ryan Huang

Closed-loop, policy-driven and LLM-augmented overload mitigation for ZooKeeper clusters.

• Closed-loop control plane: engineered a closed-loop control plane for ZooKeeper clusters to mitigate overload failure, integrating Prometheus telemetry and HAProxy / tc for traffic shaping.
• Mitigation / RCA action library: implemented a library of atomic mitigation actions, including network throttling (tcconfig), dynamic load balancing (HAProxy Runtime API), JVM heap tuning and disk I/O control (fsync), packaged as auditable scripts that any controller can invoke safely.
• Load injection & evaluator: built a custom load generator (zkbench) supporting multi-stage traffic (warmup → spike → cooldown) to stress-test resilience, and a closed-loop evaluator that correlates injection rates, SLO violations and goodput across control strategies.
• Agentic controller: prototyped a Claude Code styled controller (GPT-4.1 with Model Context Protocol tools) that consumes metrics and log summaries to do root cause analysis and select mitigation actions, enabling comparison between static policies and agentic reasoning on complex failure patterns; tuned context-window usage with a log processor to cut the number of cycles.

• ZooKeeper
• Prometheus
• HAProxy
• tc
• JVM
• zkbench
• MCP
• GPT-4.1

Search Engine "Crawl Me Maybe" in C++

UMich EECS 498 · System Design for Search Engine · Instructor Nicole Hamilton

A complete web search engine built from scratch in C++ by a team of four, crawling 210M pages and serving queries from a 1 TB inverted index on 20 GCP servers.

• Product demo: built a complete search engine in a team of 4; crawled 210M websites within 2 days, indexed into a 1 TB inverted index, average query time 200 ms with p99 tail latency of 4 s, distributed across 20 GCP servers.
• Inverted index read-write storage system: hierarchical storage design using mmap for disk I/O, UTF-8 + VByte encoding and a string pool for variable-length strings; implemented a recursive skip-list tree and position-list cursor for fast posting-list walks; high-concurrency multithreading and a zero-copy data path that made index writing compute-bound.
• Constraint solver design: contributed a recursive constraint-solver tree built from the query compiler’s AST, with submatching and merging; supports AND / OR / Phrase / NOT logic.
• Ranker design: contributed a benchmark of ~100 hot query terms against Google/Bing and tuned the dynamic ranker weights, including BM25 tf-idf, domain-name matching and last-path matching.

• C++20
• Inverted Index
• mmap
• VByte
• Skip Lists
• Constraint Solver
• BM25
• GCP

Origami-Inspired Soft Robotic Arm

HDR Lab @ UMich · Advised by Xiaonan Huang

Best Poster Award, IEEE ICRA 2025 Workshop

A pneumatic Kresling-origami arm for confined-space manipulation, from firmware to PCB.

• Kresling origami + pneumatic actuation for confined-space manipulation.
• Led STM32 & Orange Pi firmware (dynamics/PID, CAN/I²C); C++/Rust core algorithms; contributed to PCB design.
• Demos/extended abstracts: ICRA 2025 Workshop (Best Poster), RoboSoft 2025 Workshop, ICON 2025.

• STM32
• Orange Pi
• CAN
• I²C
• Rust
• C++
• PCB

Cuda Proxy Player

UMich CSE 582 · Advanced Operating Systems · Advised by Prof. Ryan Huang

A hybrid CUDA runtime that mixes CUDA Graphs with persistent kernels to cut launch overhead for MoE.

• Designed a hybrid CUDA runtime combining CUDA Graphs for stable compute paths and persistent kernels for irregular on-device tasks.
• Reduced kernel launch overhead and tail latency without brittle fusion, enabling dynamic routing and static graph reuse.
• Implemented bucket-based static pooling, piecewise graph capture, and stream-level synchronization for efficient MoE execution.

• CUDA Graphs
• Persistent Kernels
• MoE
• Streams

Cloud VLM for AV Control

UMich CSE 589 · Advanced Networking · Advised by Prof. Z. Morley Mao

A local-cloud VLM pipeline for autonomous driving that adapts offloading to network conditions.

• Designed a hybrid local–cloud pipeline combining OpenEMMA and large VLMs for efficient & reliable decision-making.
• Selective offloading of static-scene context (e.g., construction, obstacles) to cloud models; dynamic agents handled locally.
• Network-aware control adapts send rate and compression based on latency to balance accuracy and responsiveness.

• OpenEMMA
• VLM
• Offloading
• Network-aware Control

Auto Sentry Robot Control

RoboMaster @ SJTU

National Champion, RoboMaster 2023 (DJI)

Control stack for a championship-winning sentry robot, from gimbal PID to lead-angle shooting.

• STM32-F407 platform; dual-gimbal stabilization with a tuned PID controller; high-response four-steering-wheel chassis.
• CAN/UART pipelines for CV and LiDAR; IMU-based absolute-pose control.
• High-precision shooting with flywheel speed and lead-angle compensation.

• STM32-F407
• PID
• CAN/UART
• IMU
• LiDAR