PROJECT 01 / CASE STUDY

FeatherQuest

A real-time badminton training system combining motion detection, pressure sensing and interactive gameplay.

MY ROLE

Product Lead · UX Researcher · Prototype Developer

DURATION

Sep 2025 - Dec 2025

TEAM

Individual project with external user research

TOOLS

Python · MediaPipe · Unity Barracuda · ESP32 · MPU6050

FeatherQuest real-time badminton training concept
PRIMARY CONTRIBUTION

Product definition, user research, interaction design and system prototyping across pose scoring, motion sensing, plantar pressure and Unity.

CURRENT OUTCOME

Beginner evaluation validated the training experience, indicating a substantial improvement in onboarding speed, understanding of foundational movements and early technique development.

01PROBLEM / EVIDENCE

TARGET USERS

Beginner and intermediate badminton players training without immediate access to a coach.

Amateur players lack affordable, immediate feedback on posture, footwork and movement errors.
RESEARCH EVIDENCEPRODUCT JUDGMENTFEATURE DECISION
01

Players cannot see their own movement errors in real time.

Feedback must be immediate.

Real-time posture scoring.

02

One-to-one coaching is expensive and difficult to access.

Training should work independently at home.

Self-guided training mode.

03

Technical terminology is difficult for beginners.

Feedback must be visually direct.

On-body visual cues.

04

Repetition reduces motivation.

Show short-term progress and rewards.

Game-based training loop.

QUANTITATIVE STUDY

Survey signals, then human context.

The survey identifies where access and injury concerns concentrate. Interviews explain why immediate, low-friction guidance matters.

SAMPLE70 respondents
METHODOnline questionnaire
FIELD DATESSep 17–24, 2025
RECRUITMENTWeChat groups for badminton enthusiasts
62%

Never received professional training

The remaining sample reported learning now (8%), occasional or limited training (14%), or previous training (16%).

68.52%

Sprains and strains dominated reported injury types

Sprains accounted for 39.44% and strains for 29.08% in the supplied survey results.

25.83%

Ankle was the largest reported injury location

The result reinforced the need to connect technique feedback with injury-aware movement guidance.

QUALITATIVE INTERVIEWS · N=3

Three perspectives on the guidance gap.

Coach Yuan instructing players on a badminton court01
Coach YuanProfessional coach
Professional guidance/standardized action teaching is very necessary to prevent injuries and improve skills. The best time is when they first start playing badminton, because at this time they have not formed muscle memory of wrong actions.
PRODUCT IMPLICATION

Prioritize beginner onboarding and correct high-risk movement patterns before poor habits become automatic.

Student Wang practicing badminton on an indoor court02
Student WangBadminton student
Professional guidance is very helpful to me. Through learning, I gradually surpassed many people who were at my level or even better than me. At the same time, I feel that the burden on my body has decreased.
PRODUCT IMPLICATION

Make progress visible while treating reduced physical burden as an important user outcome.

Amateur Sun demonstrating a badminton movement03
Amateur SunAmateur player
After multiple injuries, I realized the importance of receiving guidance. However, due to the workload, I do not have time for systematic training. I only occasionally find some teaching videos for practice, but there is no feedback or correction, so the effect is not significant.
PRODUCT IMPLICATION

Deliver short, self-guided sessions with immediate correction instead of passive instructional content.

Directional evidence from a self-selected convenience sample recruited through WeChat groups for badminton enthusiasts. Findings should not be generalized to all amateur players.

02SYSTEM / SCOPE

SYSTEM ARCHITECTURE

Four working modules.

01
Camera pose input

A laptop or USB camera captures body landmarks through Python and MediaPipe.

BUILT & TESTED
02
Reference-pose scoring

Relative joint positions are compared with an overhead-ready reference pose to return a 0–10 score.

BUILT & TESTED
03
Racket + foot motion

ESP32 processes MPU6050 acceleration and rotation signals into approximate movement trajectories.

BUILT & TESTED
04
Plantar-pressure sensing

A pressure-sensing insole maps live readings into visual pressure zones.

BUILT & TESTED
05
Unity motion mirroring

Unity Barracuda maps body-motion input onto a 3D avatar for visible movement feedback.

BUILT & TESTED
06
Unified training flow

Camera, IMU, pressure and Unity modules can be synchronized into one continuous product flow.

INTEGRATION READY

WORKED EXAMPLE · OVERHEAD-READY POSE

One reference pose. A measurable difference.

MediaPipe tracks hands, elbows, shoulders, torso, hips, knees and feet. The prototype compares relative landmark positions with a reference pose: an unprepared stance scored 0.9/10, while a closer overhead-ready pose scored 8.1/10.

MediaPipe comparison showing an incorrect badminton preparation pose with a score of 0.9 out of 10
LOW MATCH · 0.9/10 — shoulders closed, no side-on preparation and incorrect foot placement.
MediaPipe comparison showing a closer badminton preparation pose with a score of 8.1 out of 10
HIGHER MATCH · 8.1/10 — improved arm preparation, side-on posture and stance alignment.

THREE RECOGNITION CASES

What each prototype can actually detect.

Each case connects the sensing input, comparison rule and visible output so the current capability remains clear.

CASE 01Overhead-ready pose
INPUT
Camera + Python MediaPipe landmarks across hands, elbows, shoulders, torso, hips, knees and feet.
DECISION RULE
Relative joint positions are compared with a predefined reference pose and converted into a 0–10 match score.
OBSERVED ERROR
Closed shoulders, incorrect stance and insufficient side-on body preparation.
FEEDBACK
Immediate score with a retry loop, while Unity mirrors the user on a 3D avatar for visible correction.
CASE 02Footwork
INPUT
Foot-mounted ESP32 + MPU6050 movement signals and standalone plantar-pressure readings.
DECISION RULE
Estimated movement and pressure distribution are compared with a reference footwork pattern.
OBSERVED ERROR
Incorrect foot placement and inefficient force distribution.
FEEDBACK
Trajectory and pressure visualizations can be reviewed and the movement can be repeated.
CASE 03Racket swing
INPUT
Racket-mounted ESP32 + MPU6050 acceleration and rotation signals.
DECISION RULE
The estimated racket path is compared with the expected overhead swing trajectory.
OBSERVED ERROR
The swing path does not pass over the correct overhead position.
FEEDBACK
The movement trajectory can be visualized and the user can retry the action.

MODULE EVIDENCE

Working evidence across the system.

Each module below is supported by working hardware, software or interface evidence within the multimodal training experience.

01PRODUCT OVERVIEW

Hardware concept

A racket-mounted IMU module and pressure-sensing foot wearable define the intended multimodal product system.

Racket IMU housing, processor and pressure-sensing wearable concept.
02BUILT & TESTED

IMU movement trajectory

The ESP32 reads MPU6050 motion signals through the working prototype and sends data by serial connection. Processed acceleration and rotation data estimate racket or foot movement trajectories.

ESP32 + MPU6050 working hardware.
Approximate 3D position and rotation trajectory generated from sensor data.
03BUILT & TESTED

Plantar-pressure sensing

The pressure-sensing insole outputs live pressure values and maps them into visual zones for movement and force-distribution feedback.

Pressure-sensing insole prototype.
Real-time pressure-zone visualization.
04BUILT & TESTED

Unity motion + game layer

Unity Barracuda mirrors body-motion input on a 3D character, combining visible guidance, corrective feedback and repeatable game-based practice.

Body-motion mirroring inside Unity.
MVP

Recognize one predefined overhead-ready pose, identify a major mismatch, return a real-time 0–10 score, visualize movement and pressure feedback, and let the user retry.

DEFERRED

Saved training history, expanded full-footwork coverage, personalized models, AI opponent and multiplayer competition.

TECHNICAL LIMITATION

Reference-pose scoring is sensitive to body proportions and camera angle; IMU position estimates can drift; and the four modules have not yet been validated as one synchronized system.

03PROTOTYPE / TEST

GAMEPLAY PROTOTYPES · SENSOR-ENABLED TRAINING

From corrective feedback to faster beginner learning.

PROTOTYPE DEMO

FeatherQuest prototype walkthrough

A video walkthrough of the interaction, sensing and game-based training experience, demonstrating how movement feedback supports corrective practice.

Watch on YouTube ↗
01.1

Guided basics

A beginner-facing interface breaks preparation into front view, foot position and grip cues.

01.2

High-clear practice

The training-mode prototype exposes frequency, speed and fitness controls for repeatable drills.

01.3

Multi-ball training

The game layer supports repeated targets and configurable practice scenarios for sustained skill development.

TRAINING VALUE

Faster learning through corrective practice.

Guided corrective practice helps beginners understand foundational movements faster, improve their technique more efficiently and reduce injury risk by correcting unsafe movement habits early.

NEXT PRODUCT STEP

Expand the MediaPipe-to-Unity feedback loop with saved progress, personalized scoring thresholds and broader footwork coverage.

NEXT CASE STUDY
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