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Knowledge Technology Group (WTM)

Department of Informatics, University of Hamburg

TEXT-TO-SPEECH BASED EMOTION-AWARE HUMAN-ROBOT DIALOGUE SYSTEM

Elnur Alimirzayev Burak Can Kaplan Cornelius Weber Stefan Wermter

Abstract

The rapid progress of large language models (LLMs) has accelerated the rise of interactive AI systems, yet most remain text-only and largely emotion-agnostic. Adding text-tospeech (TTS) enables voice interaction, but current state-of-the- art TTS models mostly offer indirect, coarse control over prosody and frequently fail to realize requested emotions. This mismatch between intended content and delivered tone undermines user trust in high-stakes settings such as customer support and healthcare. Two technical obstacles cause this gap: 1) content and prosody are tightly entangled, so an inappropriate emotion can degrade intelligibility, and 2) models tend to express the emotions that are standard for the given text. Addressing these issues is essential for emotionally coherent and controllable speech in LLM-driven interactions. Our approach proposes a modular human-robot interaction system that integrates an emotion recognition in conversations model with TTS to enable emotional awareness. Due to this integration, our TTS can decide on the correct emotion to answer, select appropriate reference audio to adapt its prosody in each interaction, and generate speech of an ”emotionally intelligent” robot. Additionally, we set a new baseline for an emotional dialogue system pipeline and automated evaluation of such systems.

Architecture

Architecture Diagram

Dialogue Demos

Code Repository: https://github.com/al1ve1t/eahris

Anger Dialogue Example
Hi Nico
Hey Alex! What's up?
I had a tough day and I'm a bit mad.
Oh man, that sucks! Wanna talk about what happened? Maybe I can help a bit.
No! I don't want to talk my business with you!
That's cool, no worries! I'm here if you just need a distraction or wanna chat about something else. What's on your mind?!
Happiness Dialogue Example
Hi Nico, how are you?
Hey Alex! I'm doing great, thanks for asking! How about you, what's up?
I'm doing great too. I was asleep and was dreaming about winning a lottery!
That's awesome! What would be the first thing you but if you actually won?
I think I would go somewhere for a trim. Do you have some places in mind?
Oh, a trip sounds fun! How about a beach vacation on Hawaii? Or exploring the streets of Tokyo? Or maybe a European gateaway to places like Paris or Rome. What kind of vibe are you thinking?
Sadness Dialogue Example
Hi Nico, how are you doing?
I'm feeling pretty good, Alex! Just handing out and ready to chat. How about you?
I'm feeling sad. Just remembered my pet, which passed away a few years ago.
I'm really sorry to hear that, Alex. Losing a pet is really tough. What was your pet's name? Maybe we can chat about some happy memories you had together?
Yes thank you! It was a hamster named Phil and he passed away because of sickness..
Oh, Phil sounds like he was a special little guy. Hamsters do have a way of getting into our hearts quickly. Do you have any favorite memories with him you would like to share? It's nice to think about the good times.