Mina Maddahi

About me

Hi, I'm Mina Maddahi

I'm a UX researcher who loves understanding how people experience new technology. I plan studies, test ideas with real users, and turn what I learn into clear design decisions.

I started as a computer engineer, then completed a Master's in Design for Immersive and Creative Technology at Stockholm University. Most recently I worked in Ericsson's Audio team, where my work on VR and spatial audio led to two granted patents.

Because I can code, I build my own prototypes and work easily with developers. I'm curious, careful with details, and happiest when complex technology starts to feel simple.

Stockholm, Sweden Available now English · Farsi · Swedish (learning)
Portrait of Mina Maddahi

Selected work

Industry · Research · Academic

Case study · Ericsson Research

Testing spatial audio in VR

A VR system with real-time 3D spatial audio and an Android companion app. I built it, set it up across devices, and designed the user tests that showed how well it worked.

Role
R&D Intern, Audio team
When
Jun – Dec 2025
Methods
User testing, metrics design
Outcome
2 granted patents

Project 1 · Granted patent

HRTF personalization with real-time ITD adjustment

Spatial audio only feels real if it fits your own ears. This project lets people tune 3D sound to themselves inside the headset, just by listening and pointing.

The problem

In VR, sound is placed in 3D space using filters called HRTFs. They model how sound reaches our two ears. But every head and ear is different, so a standard filter can make sounds seem to come from the wrong direction. The usual ways to personalise it are slow or hard: measuring with microphones in the ears for hours, scanning the ears, or taking body measurements. None of these work when someone just puts on a headset.

The idea

Turn calibration into a short listening task inside VR. The user hears a sound and points to where it seems to come from. If they point too far or not far enough, the system adjusts the timing difference between the two ears (the ITD) and plays the sound again. It repeats until the sound lands where it should. The user never takes off the headset or measures anything.

Play a sound from a known direction User points where they hear it Compare heard vs. true direction Adjust ear timing until they match repeat until the sound is heard in the right place

Why it matters for users

  • No equipment and no measuring. Everything happens with the headset and headphones people already wear.
  • Fits into the experience. It can run as a short setup step before a game or a meeting, or any time sound feels off.
  • Simple to do. The only task is "point where you hear it", which anyone can understand.

What I did

  • Built the entire 3D side of the project on my own: a VR framework where users interact with objects and hear real-time 3D sound from them.
  • Created the interactive scenes in Unity and Godot that the calibration runs in.
  • Set up and tested the system across headsets and audio hardware.
  • Designed and ran user sessions, measuring how accurately people located sounds and how natural the audio felt.

Outcome. The method was granted as an Ericsson patent, with me as a co-inventor.

Project 2 · Granted patent · Shown at MWC 2026

Smooth transition for immersive audio

Immersive phone calls let you hear where each voice comes from. I built an Android app that makes that spatial sound visible and interactive, and it was used in live demos at Mobile World Congress 2026.

The context

A new 3GPP standard for mobile calls, the IVAS codec (Immersive Voice and Audio Services), brings spatial audio to everyday calls. Instead of a flat voice, you can hear people and sounds around you in 3D. The challenge is that sound is invisible. When you show the technology to people, especially in a busy, noisy setting, it is hard for them to understand what is happening and why it matters.

What I built

  • A new Android app, built from scratch in Kotlin with Android Studio, to visualise immersive audio during a call.
  • An interactive avatar that represents the audio in space. Users can interact with it and immediately hear how the sound changes, so the 3D effect becomes something you can see and play with.
  • Integrated the app with the spatial audio and tested it together with the headsets and audio hardware.

Outcome. The work was used in live immersive calls between Barcelona and Stockholm over Ericsson's network at MWC 2026, in a focus session with other 3GPP partners. It also led to a granted patent, with me as a co-inventor.

What I took away

A good visual turns an abstract technology into an experience people understand in seconds. Designing for a live demo also taught me to keep interactions simple and robust, because there is no second chance in front of an audience.

Case study · Stockholm University

TwinTurbine: a shared mixed reality digital twin

A small physical wind turbine and its virtual twin, connected in real time. Several people can watch and control it together in mixed reality. Three rounds of user testing turned a working prototype into an engaging one.

Team
4 students
When
May – Jun 2024
My part
Tangible interaction, documentation
Tools
Unity, C#, Meta Quest, Arduino

The problem

Wind turbines are hard to inspect and hard to learn about. Technicians often have to travel to the site, which is slow, costly and sometimes dangerous. Students mostly learn from textbooks and still images, which makes it hard to connect real data to what a turbine actually does.

Who we designed for

  • Engineers and technicians, who need to monitor turbines remotely and diagnose problems quickly.
  • Teachers and students, who need a safe, hands-on way to explore how turbines work.
  • First-time visitors, who need clear guidance to understand a complex system.

How the physical and virtual turbines connect

Live wind data turns both turbines. The electricity the physical turbine makes is measured and shown on a dashboard inside mixed reality.

SMHI weather wind direction, speed Mixed reality app Unity · Meta Quest ESP32 Wi-Fi · WebSockets Arduino + servo turns to the wind Physical turbine generator + light Light sensor light → voltage Live dashboard voltage, wind, location

What testing changed

Round 1

The system worked, but people found it hard to follow what was happening.

Change: added audio narration to explain each step.

Round 2

Even with a guide avatar and narration, people got bored and lost interest.

Change: more engaging visuals and a clearer, redesigned dashboard.

Round 3

External users tried it together in a shared multi-user session.

Outcome: overall positive feedback.

What I took away

A system that works technically is only the start. Users needed guidance and something to keep them interested, and we only discovered that by testing. Each round changed the design in a way we had not predicted.

Case study · Stockholm University · Academic project → research paper

AVeRT: Autonomous Vehicle Remote Tele-Assistance

When a self-driving car meets something it can't judge, a remote operator steps in. We ran a controlled VR experiment to find out which camera view and which kind of task help operators decide faster and more accurately. The project started as a group course project, and we then turned it into a research paper.

Team
Group project
Output
Research paper (2024)
Method
2×2 within-subject experiment
Participants
16 people, 256 trials

The problem

Self-driving cars still get stuck in unclear situations, such as debris on the road or unexpected roadworks. A remote operator then has to tell the car what is safe to pass and what is not. The interface they use affects how quickly and how correctly they decide, and these decisions carry real safety stakes.

Research question

How do task type (marking safe vs. unsafe objects) and camera view (driver's seat vs. overhead roof camera) affect task completion time and error rates, including false positives and false negatives?

How we studied it

  • Built 16 VR road scenes in Unity for the Varjo XR-3 headset. In each one, a car has stopped and needs help.
  • Participants marked objects with a hand pinch gesture and a pointing ray, without controllers.
  • Every participant tried all four combinations (2 tasks × 2 camera views), in a counterbalanced order to reduce learning effects.
  • A 10-minute training scene came first, so everyone was comfortable with the gesture before testing.
  • Unity logged time and errors automatically. Screen recordings helped us check unusual behaviour.
  • We cleaned outliers and analysed the data in Python with paired t-tests and a two-way repeated-measures ANOVA.

What we found

The overhead view was faster. About 8 seconds quicker per task on average (p = 0.008).
Spotting danger caused more mistakes. Marking unsafe objects had a much higher error rate (p < 0.001).

Camera view did not change accuracy in a meaningful way (38% vs. 41% errors, p = 0.22). We had expected unsafe objects to be easier, so this finding went against our hypothesis.

What it means for design

  • Offer an overhead view. A remote operator isn't limited to a driver's seat, and a bird's-eye view speeds up decisions without hurting accuracy.
  • Support the hard decisions. Judging danger is where people struggle, so cues like AR highlights or AI suggestions should focus there.

What I took away

Numbers told us what happened but not why. Next time I would add think-aloud sessions or short interviews to understand why people hesitate over unsafe objects, and measure workload, not only time and errors.

Academic projects

Stockholm University · 2023 – 2024
2024

Different Eye Interaction in Virtual Reality

Unity · Meta VR headset · C#

  • Developed a fully immersive VR project exploring different methods of eye interaction.
  • Focused on dwell time, gaze duration and pattern recognition using eye-tracking technology.
2024

TwinTurbine: Digital Twin for Tangible Turbine Simulation

Unity · Meta VR headset · C# · Python

A digital twin that lets people experience how a wind turbine works in mixed reality. Several users can monitor and control the turbine together, see its real-time data and get immediate feedback. Since a real turbine wasn't available, we used a scaled physical model that behaves like one.

  • Created a digital twin of a tangible turbine connected to Unity for real-time XR simulation.
  • Developed interaction mechanisms that let users control the turbine in virtual space through tangible input.
  • Documented the project lifecycle, focusing on XR design principles and integrating physical components with Unity.
2023

Atom Craft: A VR and Tangible Interaction Project

Unity · Meta VR headset · C# · Python

An educational VR experience about what atoms are made of. Users build a hydrogen atom (easy task) and a lithium atom (harder task) using a physical device. It helps learners of all ages discover or revise the Bohr model of the atom in an engaging, hands-on way.

  • Prototyped a tangible interface integrated with a virtual reality environment using Unity and Python.
  • Set up communication between the tangible device and the VR system for real-time interaction.
  • Wrote full project documentation covering technical workflows and user interaction design.
2023

2D and 3D Game Development in Unity

Unity (2D and 3D) · C#

  • Designed and developed several individual projects focused on gameplay mechanics, physics interactions and visual effects.
  • Built strong skills in Unity's 2D and 3D frameworks, problem solving and creative thinking.

Skills & education

Research

User testingTest designMetrics & success criteriaControlled studiesStatisticsTechnical writing

Prototyping

UnityGodotVR / ARAndroidArduino

Code

PythonC#KotlinHTMLGit
2023 – 2025

Master's, Design for Immersive and Creative Technology

Stockholm University

2010 – 2016

Bachelor's, Computer Engineering

Raja University, Iran

Let's talk.

Open to UX research and design roles in Stockholm and remote.