Hi, I am Ruben Hammele.

PhD Student in Robotics.

As a PhD candidate in the Visual Computing and Artificial Intelligence Lab at Kiel University, supervised by Sören Pirk. I work on world models and foundation models that bring this vision closer to reality. My goal is to develop AI systems that move beyond impressive demonstrations toward reliable autonomy in the physical world.

I co-founded EcoCheck, where I still build AI-powered CO₂ accounting systems, and spent several years as a freelance software and AI developer. That experience shapes how I work today: I want complex technology to hold up outside the lab, not just on paper.

My vision is to make intelligent robots a practical part of everyday life, helping people overcome physical and practical limitations and enabling society to meet the challenges of demographic change. I work toward this by developing embodied AI systems that can understand the world, learn autonomously, and reliably translate intelligence into action in the real world.

Robotics Robot Learning Vision-Language-Action Models (VLAs) Deep Learning

Resume

PUBLICATIONS

Preprint

Evaluating Early Multimodal Fusion in Discrete Latent World Models for Robot Navigation

Mohammad Safwan Mondal², Mohammad Nazeri², Ruben Hammele¹, Samira Huber¹, Alexandyr Card², Anuj Pokhrel², Daeun Song², Sören Pirk¹, Xuesu Xiao²

¹Kiel University, Germany · ²George Mason University, USA

We compare five multimodal fusion mechanisms (Shift, Scale, FiLM, Cross-Attention, and AdaLNZero) within Hydra, a discrete latent World Action Model for robot navigation, both offline and in 100 closed-loop physical robot trials under modality dropout. High-capacity operators excel offline but often degrade under physical sensor dropout, whereas restricting fusion to bounded element-wise scaling preserves the discrete latent structure and reaches up to 80% success under sensor loss.

PDF

CoRL 2026

COOL: Curiosity-Driven Object Ownership Learning for Personalized Robotic Assistance

Samira Huber^1,*, Ruben Hammele^1,*, Sören Pirk¹

¹Kiel University, Germany · ^*Equal contribution

We present COOL, a robotic framework for autonomously learning object ownership from everyday observations and maintaining a long-term spatial memory of its environment. COOL uses an agent-based curiosity-driven data collection strategy that guides the robot toward the most promising locations to gain information and refresh stale observations, enabling ownership-conditioned navigation and task execution.

Project Page Arxiv PDF Code

Preprint

Hydra: A Navigation World Action Model with Discrete Latent Planning and Continuous Flow-Matching Execution

Mohammad Nazeri², Alexandyr Card², Samira Huber¹, Anuj Pokhrel², Yujun Wang², Ruben Hammele¹, Daeun Song², Sören Pirk¹, Xuesu Xiao²

¹Kiel University, Germany · ²George Mason University, USA

We present Hydra, a discrete World Action Model for robot navigation that learns a shared latent space over visual states, physical poses, and control actions, compressed into discrete vocabularies via vector-quantized bottlenecks. Candidate plans are sampled and ranked in this space through Discrete Latent Planning, and conditional flow matching turns the selected discrete intents into smooth, continuous trajectories, outperforming current navigation world models on two physical robot platforms.

Project Page Arxiv PDF

EDUCATION

2025 —
Present

PhD in Computer Science

Kiel University

Research group Visual Computing and Artificial Intelligence, supervised by Sören Pirk. Focus on robotics, deep learning, and machine learning.

Oct 2019 —
Nov 2021

M.Sc. Entrepreneurship in Digital Technologies

University of Lübeck

Grade 1.2. Focus: Machine Learning and Entrepreneurship.

Mar 2017 —
Sep 2019

B.Sc. Business Information Systems

Kiel University of Applied Sciences

Sep 2015 —
Feb 2017

B.A. Agricultural Economics

Kiel University of Applied Sciences

85 ECTS completed.

EXPERIENCE

May 2026 —
Present

PhD Candidate: Embodied AI & Robotics

Kiel University

World models and robot learning for real-world robotic autonomy. Developing and evaluating learning-based systems in simulation and on physical robots. First-author publication at CoRL 2026.

Sep 2025 —
Apr 2026

PhD Candidate

University of Lübeck

Research and teaching in machine learning, specifically in information extraction and causal inference.

Nov 2021 —
Present

CEO & Co-Founder

EcoCheck

AI systems and entrepreneurship. Spearheaded AI-powered CO₂ accounting systems.

May 2022 —
Aug 2025

Freelancer: Software Development & AI

Self-employed

Delivered custom AI-driven software solutions and provided specialized IT consulting for diverse clients.

Oct 2022 —
Jun 2023

Research Associate

Kiel University of Applied Sciences

Conducted AI feasibility studies for companies in the area.

Jul 2017 —
Jun 2018

Working Student

HSH Nordbank AG · Kiel, Germany

Development of automated job control systems using Control-M, Shell and Java.

Aug 2012 —
Jun 2015

Apprenticeship

Helios Kliniken GmbH · Schleswig, Germany

Software engineering and SAP enterprise development.

TEACHING

Generative AI

Kiel University, Summer 2026

Teaching the principles and methods of generative AI, including variational autoencoders, diffusion models, and large language models, with hands-on practical exercises.

AWARDS, TALKS & MEDIA

Media

Lübecker Nachrichten: EcoCheck Feature

Interviewed about the founding story of EcoCheck, how the startup developed, and what to expect from EcoCheck this year.

Read

Funding

State funds the Lübeck-based EcoCheck project with around €170,000

The state of Schleswig-Holstein is funding the EcoCheck AI project with around €170,000 to help consumers make more sustainable grocery choices.

Read

Media

BNN | Badische Neueste Nachrichten: EcoCheck Feature

EcoCheck featured in the BNN, highlighting how anyone can eat more climate-friendly — especially timely with the recent severe weather and flooding in southern Germany.

NDR Schleswig-Holstein Magazine: EcoCheck Feature

Media

Schleswig-Holstein Magazine: EcoCheck on NDR

Samira Huber and Ruben Hammele make sustainable shopping possible with EcoCheck. NDR accompanied the founders on a shopping trip and showed how the app displays the emissions of purchased groceries.

Watch

Media

Tagesschau: EcoCheck Report

A friend spotted an EcoCheck article in the Tagesschau app. Following last week’s NDR interview, several formats were produced — with more coverage coming soon.

Media

Consumer Advice Center: EcoCheck App Test

The consumer advice center tested EcoCheck and praised the app for transparently and consistently communicating climate protection and sustainability — while looking great, too.

Read

Media

Lübecker Nachrichten: EcoCheck and the Story Behind It

In the June 2/3 edition, the Lübecker Nachrichten published an exciting article about EcoCheck and the story behind it, featuring Ruben Hammele and Samira Huber.

Accelerator

Impact Hub Berlin: Sustainable Food Innovators

EcoCheck was featured as one of the Sustainable Food innovators in Impact Hub Berlin's Impact Accelerator, alongside startups advancing urban farming, upcycled food, and vertical farming.

Get ticket

Award

Startup Days Lübeck 2024: Impact Award

EcoCheck won the Impact Award at the StartUp Days Lübeck 2024 pitch competition, competing against innovative startups from across Schleswig-Holstein.

Media

Galileo: EcoCheck on TV

EcoCheck was featured on Galileo, presenting the project to a nationwide TV audience and sparking a wave of positive feedback and rising downloads.

Podcast

BNE Digital: Interview with Ruben Hammele

Students interviewed Ruben Hammele about the EcoCheck story for BNE Digital, resulting in a multimedia online article with a podcast episode.

Read & listen

Award

Sparkasse zu Lübeck Founder Prize 2023

EcoCheck won the Sparkasse zu Lübeck 2023 founder prize and its €10,000 award for making hidden emissions visible and helping consumers make more sustainable purchasing decisions.

Read

Partnership

Holiday Inn Lübeck x EcoCheck: CO₂-Labels on the Menu

Holiday Inn Lübeck and EcoCheck partnered to add CO₂ labels to every dish on the new “Kochwerk Lübeck” menu, giving guests transparent information to make more sustainable choices.

Media

Klartext für Start-ups: EcoCheck Interview

Samira Huber and Ruben Hammele talk about the challenges they overcame in their early startup journey in the GründerCube video series “Klartext für Start-ups”.

Watch

Funding

EcoCheck receives EXIST founder scholarship

EcoCheck will be supported over the next year by the EXIST founder scholarship. Thanks to GründerCube for the continuous support!

Panel talk

DiWoKiel: Silicon Valley x Start-ups

Samira Huber joined the DiWoKiel panel talk on “Silicon Valley x Start-ups: Accelerate your Success” — a great opportunity for networking and learning during Digital Week Kiel.

Accelerator

Impact Factory by Anthropia

EcoCheck spent five months in the Impact Factory in Duisburg, joining a strong community of startups focused on social and economic sustainability through coaching and team exchange. Now entering the Scale-Up phase.

Panel talk

Transatlantic Innovation Week 23: Kiel x San Francisco

Samira Huber joined a panel talk during the Transatlantic Innovation Week 23 organized by The Bay Areas e.V., discussing the transatlantic city partnership between Kiel and San Francisco and sharing insights from the recent Silicon Valley trip as winner of the Überflieger Prize.

Panel talk

Netlight Code Pub: Women in Tech

Samira Huber shared her experiences at Netlight’s Code Pub, a meet-up for women and non-binary people interested in IT, alongside Sophie-Catherine Ohlsen and Sandra Roggow.

Media

IHK Magazine: EcoCheck on the Cover

Samira Huber and Ruben Hammele are featured on the cover of the IHK magazine as one of the Lübeck startups from the GATEWAY49 program.

Award

Überflieger 2022: Trip to Silicon Valley

EcoCheck was selected as one of the Überflieger 2022 winners, earning an intensive week in Silicon Valley and San Francisco with investor meetings and networking.

Media

SWR3: Sustomer on the Radio

Samira Huber was interviewed by SWR3 about Sustomer (now EcoCheck), sharing how the startup helps people make environmentally friendly choices.

Media

Badische Neueste Nachrichten & Badisches Tagblatt: EcoCheck in the Newspaper

EcoCheck was featured in the Badische Neueste Nachrichten and Badisches Tagblatt, with a noticeable boost in downloads showing that print media still reaches many readers.

Award

Female StartAperitivo: Finalist

Samira Huber pitched EcoCheck at the Female StartAperitivo finale in Hamburg, celebrating a supportive community of female founders and connecting with investors.

Media

BUDNI Die Perle: EcoCheck in the Customer Magazine

EcoCheck (then Sustomer) is featured in the BUDNI customer magazine “Die Perle” on page 55, explaining how the app makes sustainable shopping easier and how the idea came about.

Accelerator

GATEWAY49: Batch 4 Winner

EcoCheck was selected as one of the winning teams for GATEWAY49 Batch 4 after a pitch marathon with 32 teams, joining the accelerator program at Technikzentrum Lübeck.