Gazihan Alankus

Towards customizable games for stroke rehabilitation

Stroke is the leading cause of long term disability among adults in industrialized nations. The partial paralysis that stroke patients often experience can make independent living difficult or impossible. Research suggests that many of these patients could recover by performing hundreds of daily repetitions of motions with their affected limbs. Yet, only 31% of patients perform the exercises recommended by their therapists. Home-based stroke rehabilitation games may help motivate stroke patients to perform the necessary exercises to recover. In this paper, we describe a formative study in which we designed and user tested stroke rehabilitation games with both stroke patients and therapists. We describe the lessons we learned about what makes games useful from a therapeutic point of view.

Stroke Therapy through Motion-Based Games: A Case Study

In the United States alone, more than five million people are living with long term motor impairments caused by a stroke. Recently, video games with affordable motion-based input devices have been proposed as a part of therapy to help people recover lost range of motion and motor control. While researchers have demonstrated the potential utility of therapeutic games through controlled studies, relatively little work has explored their long-term home-based use. We conducted a six-week home study with a 62-year-old woman who was seventeen years post-stroke. She played therapeutic games for approximately one hour a day, five days a week. Over the six weeks, she recovered significant motor abilities, which is unexpected given the time since her stroke. We explore detecting such improvements early, using game logs for daily measurements of motor ability to complement the standard measurements that are taken less often. Through observations and interviews, we present lessons learned about the barriers and opportunities that arise from long-term home-based use of therapeutic games.

Stroke therapy through motion-based games: a case study

In the United States alone, more than five million people are living with long term motor impairments caused by a stroke. Video game-based therapies show promise in helping people recover lost range of motion and motor control. While researchers have demonstrated the potential utility of game-based rehabilitation through controlled studies, relatively little work has explored longer-term home-based use of therapeutic games. We conducted a six-week home study with a 62 year old woman who was seventeen years post-stroke. She played therapeutic games for approximately one hour a day, five days a week. Over the six weeks, she recovered significant motor abilities, which is unexpected given the time since her stroke. Through observations and interviews, we present lessons learned about the barriers and opportunities that arise from long-term home-based use of therapeutic games.

Automated motion synthesis for dancing characters

In this paper, we present a technique to automatically synthesize dancing motions for arbitrary songs with dance beats. Our technique is based on analysing a musical tune (can be a song or melody) and synthesizing a motion for the virtual character where the characters movement synchronizes to the musical beats. In order to analyse beats of the tune, we developed a fast algorithm. Our motion synthesis algorithm analyses library of stock motions and generates new sequences of movements that were not described in the library. We show that our motion synthesis algorithm is better than previous dance generation techniques. We also present two algorithms to synchronize dance moves and musical beats: a fast greedy algorithm, and a genetic algorithm. Our experimental results show that we can generate new sequences of dance figures in which the dancer reacts to music and dances in synchronization with the music. Copyright

Reducing compensatory motions in video games for stroke rehabilitation

Stroke is the leading cause of long-term disability among adults in industrialized nations; approximately 80% of people who survive a stroke experience motor disabilities. Recovery requires hundreds of daily repetitions of therapeutic exercises, often without therapist supervision. When performing therapy alone, people with limited motion often compensate for the lack of motion in one joint by moving another one. This compensation can impede the recovery progress and create new health problems. In this work we contribute (1) a methodology to reliably sense compensatory torso motion in the context of shoulder exercises done by persons with stroke and (2) the design and experimental evaluation of operant-conditioning-based strategies for games that aim to reduce compensatory torso motion. Our results show that these strategies significantly reduce compensatory motions compared to alternatives.

Spatiotemporal query strategies for navigation in dynamic sensor network environments

Autonomous mobile agent navigation is crucial to many mission-critical applications (e.g., search and rescue missions in a disaster area). In this paper, we present how sensor networks may assist probabilistic roadmap methods (PRMs), a class of efficient navigation algorithms particularly suitable for dynamic environments. A key challenge of applying PRM algorithms in dynamic environment is that they require the spatiotemporal sensing of the environment to solve a given navigation problem. To facilitate navigation, we propose a set of query strategies that allow a mobile agent to periodically collect real-time information (e.g., fire conditions) about the environment through a sensor network. Such strategies include local spatiotemporal query (query of spatial neighborhood), global spatiotemporal query (query of all sensors), and border query (query of the border of danger fields). We investigate the impact of different query strategies through simulations under a set of realistic fire conditions. We also evaluate the feasibility of our approach using a real robot and real motes. Our results demonstrate that (1) spatiotemporal queries from a sensor network result in significantly better navigation performance than traditional approaches based on on-board sensors of a robot; (2) the area of local queries represent a tradeoff between communication cost and navigation performance; (3) through in-network processing our border query strategy achieves the best navigation performance at a small fraction of communication cost compared to global spatiotemporal queries.

Roadmap query for sensor network assisted navigation in dynamic environments

Mobile entity navigation in dynamic environments is an essential part of many mission critical applications like search and rescue and fire fighting. The dynamism of the environment necessitates the mobile entity to constantly maintain a high degree of awareness of the changing environment. This criteria makes it difficult to achieve good navigation performance by using just on-board sensors and existing navigation methods and motivates the use of wireless sensor networks (WSNs) to aid navigation. In this paper, we present a novel approach that integrates a roadmap based navigation algorithm with a novel WSN query protocol called Roadmap Query (RQ). RQ enables collection of frequent, up-to-date information about the surrounding environment, thus allowing the mobile entity to make good navigation decisions. Simulation results under realistic fire scenarios show that in highly dynamic environments RQ outperforms existing approaches in both navigation performance and communication cost. We also present a mobile agent based implementation of RQ along with preliminary experimental results, on Mica2 motes.

Adaptive Embedded Roadmaps For Sensor Networks

In this paper, we propose a new approach to wireless sensor network assisted navigation while avoiding moving dangers. Our approach relies on an embedded roadmap in the sensor network that always contains safe paths. The roadmap is adaptive, i.e., it adapts its topology to changing dangers. Mobile robots in the environment use the roadmap to reach their destinations. We evaluated the performance of embedded roadmap both in simulations using realistic conditions and with real hardware. Our results show that the proposed navigation algorithm is better suited for sensor networks than traditional navigation field based algorithms. Our observations suggest that there are two drawbacks of traditional navigation field based algorithms, (i) increased power consumption, (ii) message congestion that can prevent important danger avoidance messages to be received by the robots. In contrast, our approach significantly reduces the number of messages on the network (up to 160 times in some scenarios) while increasing the navigation performance.

Use of computer games as an intervention for stroke.

Abstract Current rehabilitation for persons with hemiparesis after stroke requires high numbers of repetitions to be in accordance with contemporary motor learning principles. The motivational characteristics of computer games can be harnessed to create engaging interventions for persons with hemiparesis after stroke that incorporate this high number of repetitions. The purpose of this case report was to test the feasibility of using computer games as a 6-week home therapy intervention to improve upper extremity function for a person with stroke. One person with left upper extremity hemiparesis after stroke participated in a 6-week home therapy computer game intervention. The games were customized to her preferences and abilities and modified weekly. Her performance was tracked and analyzed. Data from pre-, mid-, and postintervention testing using standard upper extremity measures and the Reaching Performance Scale (RPS) were analyzed. After 3 weeks, the participant demonstrated increased upper extremity range of motion at the shoulder and decreased compensatory trunk movements during reaching tasks. After 6 weeks, she showed functional gains in activities of daily living (ADLs) and instrumental ADLs despite no further improvements on the RPS. Results indicate that computer games have the potential to be a useful intervention for people with stroke. Future work will add additional support to quantify the effectiveness of the games as a home therapy intervention for persons with stroke.

Motion-Based Video Games for Stroke Rehabilitation with Reduced Compensatory Motions

................................................................................................................................. ii Acknowledgments ..................................................................................................................... iv List of Tables ........................................................................................................................... x List of Figures .......................................................................................................................... xi