Perttu Hämäläinen

Perttu Hämäläinen

Associate Professor
Associate Professor
A806 Department of Art and Media
Professor (Associate Professor)
Computer Science - Visual Computing (VisualComputing)

I'm a tenured associate professor of computer games. I work on topics such as gameplay innovation, understanding player experience, and developing novel game development tools, typically building on a foundation of AI, machine learning, human-computer interaction, and psychology.

See my homepage for papers, projects, videos etc.

Sähköposti
[email protected]
Puhelinnumero
+358505967735

Osaamisalueet

games, AI, human-computer interaction, machine learning, Virtual Reality, Extended Reality

Tutkimusryhmät

  • Computer Science Professors, Professor (Associate Professor)
  • Computer Science - Visual Computing (VisualComputing), Professor (Associate Professor)
  • Professorship Hämäläinen Perttu, Professor (Associate Professor)

Julkaisut

Understanding the Design of Emotionally Impactful Game Feel

Prabhav Bhatnagar, Markus Laattala, Supriya Dutta, Perttu Hämäläinen 2024 CHI-PLAY Companion 2024 - Companion Proceedings of the Annual Symposium on Computer-Human Interaction in Play

Grand Challenges in SportsHCI

Don Samitha Elvitigala, Armağan Karahanoğlu, Andrii Matviienko, Laia Turmo Vidal, Dees Postma, Michael Jones, Maria F. Montoya, Daniel Harrison, Lars Elbæk, Florian Daiber, Lisa Anneke Burr, Rakesh Patibanda, Paolo Buono, Perttu Hämäläinen, Robby van Delden, Regina Bernhaupt, Xipei Ren, Vincent van Rheden, Fabio Zambetta, Elise van den Hoven, Carine Lallemand, Dennis Reidsma, Florian Mueller 2024 CHI 2024 - Proceedings of the 2024 CHI Conference on Human Factors in Computing Systems

SIM2VR: Towards Automated Biomechanical Testing in VR

Florian Fischer, Aleksi Ikkala, Markus Klar, Arthur Fleig, Miroslav Bachinski, Roderick Murray-Smith, Perttu Hämäläinen, Antti Oulasvirta, Jörg Müller 2024 UIST '24: Proceedings of the 37th Annual ACM Symposium on User Interface Software and Technology

Duet: VR Pair Dancing with Partner Movement Manipulation

Markus Laattala, Perttu Hämäläinen 2024 CHI-PLAY Companion 2024 - Companion Proceedings of the Annual Symposium on Computer-Human Interaction in Play

WAVE : Anticipatory Movement Visualization for VR Dancing

Markus Laattala, Roosa Piitulainen, Nadia Ady, Monica Tamariz, Perttu Hämäläinen 2024 CHI '24: Proceedings of the 2024 CHI Conference on Human Factors in Computing Systems

Comic-making to Study Game-making: Using Comics in Qualitative Longitudinal Research on Game Development

Solip Park, Perttu Hämäläinen, Annakaisa Kultima 2024 CHI 2024 - Proceedings of the 2024 CHI Conference on Human Factors in Computing Systems

Contextual Policies Enable Efficient and Interpretable Inverse Reinforcement Learning for Populations

Ville Tanskanen, Chang Rajani, Perttu Hämäläinen, Christian Guckelsberger, Arto Klami 2024 Transactions on Machine Learning Research

Towards Understanding Waiting in Video Games

Nina Tepponen, Prabhav Bhatnagar, Perttu Hämäläinen 2024 CHI-PLAY Companion 2024 - Companion Proceedings of the Annual Symposium on Computer-Human Interaction in Play

Generating Role-Playing Game Quests With GPT Language Models

Susanna Värtinen, Perttu Hämäläinen, Christian Guckelsberger 2024 IEEE Transactions on Games

Discovering Fatigued Movements for Virtual Character Animation

Noshaba Cheema, Rui Xu, Nam Hee Kim, Perttu Hämäläinen, Vladislav Golyanik, Marc Habermann, Christian Theobalt, Philipp Slusallek 2023 Proceedings - SIGGRAPH Asia 2023 Conference Papers, SA 2023

Evaluating Large Language Models in Generating Synthetic HCI Research Data: a Case Study

Perttu Hämäläinen, Mikke Tavast, Anton Kunnari 2023 Proceedings of the 2023 CHI Conference on Human Factors in Computing Systems (CHI ’23)

“I Feel My Abs”: Exploring Non-standing VR Locomotion

Reetu Kontio, Markus Laattala, Robin Welsch, Perttu Hämäläinen 2023 Proceedings of the ACM on Human-Computer Interaction

Technology, Movement, and Play Is Hampering and Boosting Interactive Play

Robby Van Delden, Dennis Reidsma, Dees Postma, Joris Weijdom, Elena Márquez Segura, Laia Turmo Vidal, José Manuel Vega-Cebrián, Ana Tajadura-Jiménez, Annika Waern, Solip Park, Perttu Hämäläinen, José Maria Font, Mats Johnsson, Lærke Schjødt Rasmussen, Lars Elbæk 2023

"An Adapt-or-Die Type of Situation”: Perception, Adoption, and Use of Text-To-Image-Generation AI by Game Industry Professionals

Veera Vimpari, Annakaisa Kultima, Perttu Hämäläinen, Christian Guckelsberger 2023 Proceedings of the ACM on Human-Computer Interaction

Learning Task-Agnostic Action Spaces for Movement Optimization

Amin Babadi, Michiel Van de Panne, Caren Liu, Perttu Hamalainen 2022 IEEE Transactions on Visualization and Computer Graphics

Cine-AI: Generating Video Game Cutscenes in the Style of Human Directors

Inan Evin, Perttu Hämäläinen, Christian Guckelsberger 2022 Proceedings of the ACM on Human-Computer Interaction

Neural Language Models as What If? -Engines for HCI Research

Perttu Hämäläinen, Mikke Tavast, Anton Kunnari 2022 27th International Conference on Intelligent User Interfaces, IUI 2022 Companion

Visualizing Movement Control Optimization Landscapes

Perttu Hämäläinen, Juuso Toikka, Amin Babadi, C Karen Liu 2022 IEEE Transactions on Visualization and Computer Graphics

Breathing Life Into Biomechanical User Models

Aleksi Ikkala, Florian Fischer, Markus Klar, Miroslav Bachinski, Arthur Fleig, Andrew Howes, Perttu Hämäläinen, Jörg Müller, Roderick Murray-Smith, Antti Oulasvirta 2022 UIST '22: Proceedings of the 35th Annual ACM Symposium on User Interface Software and Technology

Converting Biomechanical Models from OpenSim to MuJoCo

Aleksi Ikkala, Perttu Hämäläinen 2022 Converging Clinical and Engineering Research on Neurorehabilitation IV

Learning High-Risk High-Precision Motion Control

Nam Hee Kim, Markus Kirjonen, Perttu Hämäläinen 2022 MIG '22: Proceedings of the 15th ACM SIGGRAPH Conference on Motion, Interaction and Games

Personalized Game Difficulty Prediction Using Factorization Machines

Jeppe Theiss Kristensen, Christian Guckelsberger, Paolo Burelli, Perttu Hämäläinen 2022 UIST '22: Proceedings of the 35th Annual ACM Symposium on User Interface Software and Technology

Move to Design: Tactics and Challenges of Playful Movement-based Interaction Designers’ Experiences during the Covid-19 Pandemic

Solip Park, Perttu Hämäläinen, Annakaisa Kultima, Laia Turmo Vidal, Elena Márquez Segura, Dennis Reidsma 2022 FDG '22: Proceedings of the 17th International Conference on the Foundations of Digital Games

Vibing Together: Dance Experiences in Social Virtual Reality

Roosa Piitulainen, Perttu Hämäläinen, Elisa Mekler 2022 CHI 2022 - Proceedings of the 2022 CHI Conference on Human Factors in Computing Systems

Language Models Can Generate Human-Like Self-Reports of Emotion

Mikke Tavast, Anton Kunnari, Perttu Hämäläinen 2022 27th International Conference on Intelligent User Interfaces, IUI 2022 Companion

Special Interest Group: The Present and Future of Esports in HCI

Simone Kriglstein, Anna Lisa Martin-Niedecken, Laia Turmo Vidal, Madison Klarkowski, Katja Rogers, Selen Turkay, Magy Seif El-Nasr, Elena Márquez Segura, Anders Drachen, Perttu Hämäläinen 2021

Embodied online dance learning objectives of CAROUSEL+

Kenny Mitchell, Babis Koniaris, Monica Tamariz, Jessie Kennedy, Noshaba Cheema, Elisa Mekler, Pieter van der Linden, Erik Herrmann, Perttu Hämäläinen, Iain McGregor, Philipp Slusallek, Carmen Mac Williams 2021 Proceedings - 2021 IEEE Conference on Virtual Reality and 3D User Interfaces Abstracts and Workshops, VRW 2021

VRChem: A virtual reality molecular builder

Otso Pietikäinen, Perttu Hämäläinen, Jaakko Lehtinen, Antti J. Karttunen 2021 Applied Sciences (Switzerland)

Predicting Game Difficulty and Engagement Using AI Players

Shaghayegh Roohi, Christian Guckelsberger, Asko Relas, Henri Heiskanen, Jari Takatalo, Perttu Hämäläinen 2021 Proceedings of the ACM on Human-Computer Interaction

Automatic Recognition of Playful Physical Activity Opportunities of the Urban Environment

Tuure Saloheimo, Maximus Kaos, Pia Fricker, Perttu Hämäläinen 2021 Academic Mindtrek 2021

Predicting Mid-Air Interaction Movements and Fatigue Using Deep Reinforcement Learning

Noshaba Cheema, Laura A. Frey-Law, Kourosh Naderi, Jaakko Lehtinen, Philipp Slusallek, Perttu Hämäläinen 2020 Proceedings of the 2020 CHI Conference on Human Factors in Computing Systems

3PP-R: Enabling Natural Movement in 3rd Person Virtual Reality

Inan Evin, Toni Pesola, Maximus Kaos, Tuukka M. Takala, Perttu Hämäläinen 2020 CHI PLAY 2020 - Proceedings of the Annual Symposium on Computer-Human Interaction in Play

PPO-CMA: Proximal Policy Optimization with Covariance Matrix Adaptation

Perttu Hämäläinen, Amin Babadi, Xiaoxiao Ma, Jaakko Lehtinen 2020 Proceedings of the 2020 IEEE 30th International Workshop on Machine Learning for Signal Processing, MLSP 2020

Automated Excavator Based on Reinforcement Learning and Multibody System Dynamics

Ilya Kurinov, Grzegorz Orzechowski, Perttu Hämäläinen, Aki Mikkola 2020 IEEE Access

Force approximation of the human hand in contact with a climbing wall handle

Grzegorz Orzechowski, Perttu Hämäläinen, Aki Mikkola 2020 Archive of Mechanical Engineering

Predicting Game Difficulty and Churn Without Players

Shaghayegh Roohi, Asko Relas, Jari Takatalo, Henri Heiskanen, Perttu Hämäläinen 2020 CHI PLAY 2020 - Proceedings of the Annual Symposium on Computer-Human Interaction in Play

Self-Imitation Learning of Locomotion Movements through Termination Curriculum

Amin Babadi, Kourosh Naderi, Perttu Hämäläinen 2019 Proceedings - MIG 2019

Social Play in an Exergame

Maximus D. Kaos, Ryan E. Rhodes, Perttu Hamalainen, T. C. Nicholas Graham 2019 CHI 2019: Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems

Movement Empowerment in a Multiplayer Mixed-Reality Trampoline Game

Lauri Lehtonen, Maximus Kaos, Raine Kajastila, Leo Holsti, Janne Karsisto, Sami Pekkola, Joni Vähämäki, Lassi Vapaakallio, Perttu Hämäläinen 2019 CHI PLAY '19: Proceedings of the Annual Symposium on Computer-Human Interaction in Play

A reinforcement learning approach to synthesizing climbing movements

Kourosh Naderi, Amin Babadi, Shaghayegh Roohi, Perttu Hamalainen 2019 IEEE Conference on Games 2019, CoG 2019

Recognizing Emotional Expression in Game Streams

Shaghayegh Roohi, Elisa Mekler, Mikke Tavast, Tatu Blomqvist, Perttu Hämäläinen 2019 CHI PLAY '19 - Proceedings of the Annual Symposium on Computer-Human Interaction in Play

Intelligent Middle-Level Game Control

Amin Babadi, Kourosh Naderi, Perttu Hämäläinen 2018 Proceedings of the 2018 IEEE Conference on Computational Intelligence and Games (CIG’18)

Exaggeration of Avatar Flexibility in Virtual Reality

Antti Granqvist, Tapio Takala, Jari Takatalo, Perttu Hämäläinen 2018 CHI PLAY 2018 - Proceedings of the 2018 Annual Symposium on Computer-Human Interaction in Play

Plusminus: Augmenting Physics to Promote Emergent Gameplay

Veera Hokkanen, Thomas Holmes, Hannu Koivuranta, Antti Sandberg, Helena Sorva, Juuso Toikka, Perttu Hämäläinen, Maximus Kaos 2018

Fair and Encouraging - Developing an Automatic Assessment System in Aalto Drawing

Christina Lassheikki, Iina Nokelainen, Yuanqi Shan, Maximus Kaos, Martti Raevaara, Heikka Valja, Perttu Hämäläinen 2018

Chi play 2018 welcome

Florian Mueller, Zach Toups, Daniel Johnson, Peta Wyeth, Ben Schouten, Perttu Hämäläinen, Jo Iacovides, Elisa Mekler, Hartmut Koenitz, Günter Wallner, Max Birk, Lila Bozgeyikli, Kathrin Gerling 2018 CHI PLAY 2018 - Proceedings of the 2018 Annual Symposium on Computer-Human Interaction in Play

Computer-aided imagery in sport and exercise

Kourosh Naderi, Jari Takatalo, Jari Lipsanen, Perttu Hämäläinen 2018 Proceedings Graphics Interface 2018, GI 2018

Learning Physically Based Humanoid Climbing Movements

Kourosh Naderi, Amin Babadi, Perttu Hämäläinen 2018 Computer Graphics Forum

Continuous Control Monte Carlo Tree Search Informed by Multiple Experts

Joose Julius Rajamaki, Perttu Hamalainen 2018 IEEE Transactions on Visualization and Computer Graphics

Regularizing Sampled Differential Dynamic Programming

Joose Rajamäki, Perttu Hämäläinen 2018 2018 Annual American Control Conference, ACC 2018

Neural Network Based Facial Expression Analysis of Game Events: A Cautionary Tale

Shaghayegh Roohi, Jari Takatalo, Matias Kivikangas, Perttu Hämäläinen 2018 Proceedings of the 2018 Annual Symposium on Computer-Human Interaction in Play

Review of intrinsic motivation in simulation-based game testing

Shaghayegh Roohi, Jari Takatalo, Christian Guckelsberger, Perttu Hämäläinen 2018 Proceedings of the 2018 CHI Conference on Human Factors in Computing Systems

Millainen peli koukuttaa ja tuottaa mielihyvää?

Perttu Hämäläinen, Jari Takatalo 2017 Duodecim: Lääketieteellinen aikakauskirja

Predictive Physics Simulation in Game Mechanics

Perttu Hämäläinen, Xiaoxiao Ma, Jari Takatalo, Julian Togelius 2017 Proceedings of the Annual Symposium on Computer-Human Interaction in Play

SIAK — A Game for Foreign Language Pronunciation Learning

Reima Karhila, Sari Ylinen, Seppo Enarvi, Kalle Palomäki, Aleksander Nikulin, Olli Rantula, Vertti Viitanen, Krupakar Dhinakaran, Anna-Riikka Smolander, Heini Kallio, Katja Junttila, Maria Uther, Perttu Hämäläinen, Mikko Kurimo 2017 Proceedings of the Annual Conference of the International Speech Communication Association, INTERSPEECH

Improving 3D Character Posing with a Gestural Interface

Mikko Kytö, Krupakar Dhinakaran, Aki Martikainen, Perttu Hämäläinen 2017 IEEE Computer Graphics and Applications

Discovering and synthesizing humanoid climbing movements

Kourosh Naderi, Joose Rajamäki, Perttu Hämäläinen 2017 ACM Transactions on Graphics

Towards computer-aided imagery in sport and exercise

Kourosh Naderi, Jari Takatalo, Perttu Hämäläinen 2017 CHI PLAY 2017 Extended Abstracts - Extended Abstracts Publication of the Annual Symposium on Computer-Human Interaction in Play

Augmenting sampling based controllers with machine learning

Joose Rajamäki, Perttu Hämäläinen 2017 SCA '17 : Proceedings of the ACM SIGGRAPH / Eurographics Symposium on Computer Animation

The Augmented Climbing Wall

Raine Kajastila, Leo Holsti, Perttu Hämäläinen 2016 CHI '16 Proceedings of the 2016 CHI Conference on Human Factors in Computing Systems

Virtual Ball Catching Performance in Different Camera Views

Felipe Marjalizo Alonso, Raine Kajastila, Tuukka Takala, Mikael Matveinen, Mikko Kytö, Perttu Hämäläinen 2016 Proceedings of Academic Mindtrek 2016

Sampled Differential Dynamic Programming

Joose Rajamäki, Kourosh Naderi, Ville Kyrki, Perttu Hämäläinen 2016 Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems

Online control of simulated humanoids using particle belief propagation

Perttu Hämäläinen, Joose Rajamäki, C.Karen Liu 2015 ACM Transactions on Graphics

Utilizing Gravity in Movement Based Games and Play

Perttu Hämäläinen, Joseph Marshall, Raine Kajastila, Rich Byrne, "Florian 'Floyd'" Mueller 2015 ACM CHI PLAY, London, United Kingdom, October 3-7, 2015

Motion games in real sports environments

Raine Kajastila, Perttu Hämäläinen 2015 Interactions

RT-RRT*: a real-time path planning algorithm based on RRT*

Kourosh Naderi, Joose Rajamäki, Perttu Hämäläinen 2015 MIG '15: Proceedings of the 8th ACM SIGGRAPH Conference on Motion in Games

Enhancing spatial perception and user experience in video games with volumetric shadows

Tuukka M. Takala, Perttu Hämäläinen, Mikael Matveinen, Taru Simonen, Jari Takatalo 2015 Computer-Human Interaction

Mixed reality empowerment for enhancing physical exercise

Perttu Hämäläinen, Raine Kajastila 2014 CHI'14 workshop on HCI and Sports

Online Motion Synthesis Using Sequential Monte Carlo

Perttu Hämäläinen, Sebastian Eriksson, Esa Tanskanen, Ville Kyrki, Jaakko Lehtinen 2014 ACM Transactions on Graphics

Augmented Climbing

Raine Kajastila, Perttu Hämäläinen 2014

Augmented climbing: testing prototypes in wizard of oz experiment

Raine Kajastila, Perttu Hämäläinen 2014 CHI EA '14 CHI '14 Extended Abstracts on Human Factors in Computing Systems

Benefits of 3D topos for information sharing and planning in rock climbing

Raine Kajastila, Perttu Hämäläinen 2014 Sports Technology

Empowering the Exercise: a Body-Controlled Trampoline Training Game

Raine Kajastila, Leo Holsti, Perttu Hämäläinen 2014 International Journal of Computer Science in Sport

Body-controlled trampoline training games based on computer vision

Leo Holsti, Tuukka Takala, Aki Martikainen, Raine Kajastila, Perttu Hämäläinen 2013

Enhancing spatial perception and user experience in video games with volumetric shadows

Tuukka Takala, Perttu Hämäläinen, Mikael Matveinen, Taru Simonen, Jari Takatalo 2013 Proceedings of the 25th Australian Computer-Human Interaction Conference (OzCHI '13)

Immersive 3D modeling with Blender and off-the-shelf hardware

Tuukka Takala, Meeri Mäkäräinen, Perttu Hämäläinen 2013 Proceedings of 2013 IEEE 8th Symposium on 3D User Interfaces

Voluntary pupil size change as control in eyes only interaction

Inger Ekman, Antti Poikola, Meeri Mäkäräinen, Tapio Takala, Perttu Hämäläinen 2008

Using Heart Rate to Control an Interactive Game

Ville Nenonen, Aleksi Lindblad, Ville Häkkinen, Toni Laitinen, Mikko Jouhtio, Perttu Hämäläinen 2007 IGCHI conference on Human factors in computing systems CHI '07, April 28 - May 3, San Jose, California, USA

Mutated Kd-tree Importance Sampling

Perttu Hämäläinen, Timo Aila, Tapio Takala, Jarmo Alander 2006 Mutated Kd-tree Importance Sampling, in Proceedings of the The Ninth Scandinavian Conference on Artificial Intelligence (SCAI 2006), Helsinki, Finland, 25.10.-27.10.2006

The Augmented Djembe Drum ˆ Sculpting Rhythms

Teemu Mäki-Patola, Perttu Hämäläinen, Aki Kanerva 2006 New Interfaces for Musical Expression (NIME06), Paris, France 3.6-8.6.2006

Designing Digital Sports - a Case of Mixed Reality Martial Arts

Perttu Hämäläinen 2005 International Symposium on Mixed Reality, Riika, Latvia, 20-21.5.2005

Martial Arts in Artificial Reality

Perttu Hämäläinen, Johanna Höysniemi, Tommi Ilmonen, Mikko Lindholm, Ari Nykänen 2005 ACM Conference on CHI'2005, Portland, Oregon, 2-7.4.2005

Children‚s and Parents‚ Conception of Full-Body Interaction and Violence in a Martial Arts Game

Johanna Höysniemi, Perttu Hämäläinen 2005 Conference on Designing for User eXperience (DUX 2005), San Francisco, USA, 3-5.11.2005

Children's Intuitive Gestures in Vision-based Action Games

Johanna Höysniemi, Perttu Hämäläinen, Laura Turkki, Teppo Rouvi 2005 Communications of the ACM

Genetic optimization algorithms in the design of coupled SAW filters

Johanna Meltaus, Perttu Hämäläinen, Victor P. Plessky, Martti M. Salomaa 2005 IEEE International Ultrasonics, Ferroelectrics, and Frequency Control Joint 50th Anniversary Conference, Montréal, Kanada, 23-27.8.2004

Animaatiokone - an Installation for Creating Clay Animation

Perttu Hämäläinen, Mikko Lindholm, Ari Nykänen, Johanna Höysniemi 2004 2004 Conference on Human Factors in Computing Systems (CHI'2004), Vienna, 23-30th April, 2004

Interactive Video Mirrors for Sports Training

Perttu Hämäläinen 2004 NordiCHI 2004, Tampere, 23. - 27.10.2004

Musical Computer Games Played by Singing

Perttu Hämäläinen, Teemu Mäki-Patola, Vesa Pulkki, Matti Airas 2004 7th International Conference on Digital Audio Effects (DAFx'04), Napoli, Italia, 5.-8.10.2004

Describing children's intuitive movements in a perceptive adventure game

Johanna Höysniemi, Perttu Hämäläinen 2004 Workshop on Multimodal Corpora: Models of Human Behaviour for the Specification and Evaluation of Multimodal Input and Output Interfaces, 25 May 2004, Lisbon, Portugal

Shadow Boxer - A Physically Interactive Fitness Game

Johanna Höysniemi, A. Aula, P. Auvinen, J. Hännikäinen, Perttu Hämäläinen 2004

Wizard of Oz Prototyping of Computer Vision Based Action Games for Children

Johanna Höysniemi, Perttu Hämäläinen, Laura Turkki 2004 International conference on Interaction Design and Children (IDC2004), 1-3.7.2004, Maryland, USA

Hyötypelien lajityyppimäärittely ja käyttöliittymärealismi

Sonja Kangas, Perttu Hämäläinen 2004 Lähikuva

Effect of Latency on Playing Accuracy of Two Continuous Sound Instruments Without Tactile Feedback

Teemu Mäki-Patola, Perttu Hämäläinen 2004 International Conference on Digital Audio Effects (DAFx), Napoli, Italia, 5.-8.10.2004

Latency Tolerance for Gesture Controlled Continuous Sound Instrument Without Tactile Feedback

Teemu Mäki-Patola, Perttu Hämäläinen 2004 International Computer Music Conference, Miami, USA, November 1-5, 2004.

Using peer tutoring in evaluating the usability of a physically interactive computer game with children

Johanna Höysniemi, Perttu Hämäläinen, Laura Turkki 2003 Interacting with Computers

A computer vision and hearing based user interface for a computer game for children

Perttu Hämäläinen, Johanna Höysniemi 2002 7th Ercim Workshop 'User Interfaces for All', Paris, France, October 24. - 25. 2002

Using peer tutoring in evaluation the usability of a physically interactive computer game with children

Johanna Höysniemi, Perttu Hämäläinen 2002 The International Workshop 'Interaction Design and Children'