Den teknologiska utvecklingen går i full fart i dagens samhälle och detta påverkar även utvecklandet av utbildningar och dess tillvägagångssätt. Simulatorer och simulerad inlärning tar allt mer plats inom allt från medicinsk utbildning till golfsport och har länge använts inom pilotutbildning. Implementeringen av simulatorer kan i framtiden komma att ersätta stora delar av den traditionella utbildningen då simulatorerna blir allt mer effektiva. Detta är särskilt aktuellt inom farliga och mer komplicerade situationer där felsteg kan vara kritiska. Ett exempel där kritiska tillfällen kan uppstå är inom bilkörning och körsimulatorer har därför börjat bli ett allt vanligare komplement hos trafikskolor. Denna studie hade därför som mål att undersöka körförmågan och körsäkerheten hos nybörjarförare i en simulator, för att se om auditiv och haptisk feedback har någon effekt på dessa. Till studien rekryterades 12 deltagare av låg körerfarenhet, varav fem kvinnor och sju män. Studien var experimentell med inomgruppsdesign där hälften av deltagarna började köra utan feedback medan andra halvan började med feedback. Deltagarna bytte sedan betingelse. Feedback under körning visade ingen signifikant påverkan av körförmåga eller körsäkerhet. Detta kan bero på det låga antalet deltagare då de sammanlagda avvikelserna var högre vid avsaknad av feedback. Detta resultat antyder även att nya förare inte använder sig av audio-haptiska ledtrådar i lika stor utsträckning som mer erfarna förare. / Technological advancement is traveling at high speeds in today's society and this has had a big impact on education and its approaches. Simulators and simulated learning have become more prevalent in everything from medical training to golf sports and have been used for a long time in the aviation field by training pilots. The implementation of simulators could come to replace big parts of the traditional approach in the educational field because of their high rise in effectiveness. Simulators are especially topical in dangerous and more complex situations where mishaps could be critical. One example would be driving, and driving simulators seems to be on the rise in traffic education. This study had as a goal to examine driving skills and safety in novice drivers in a driving simulator to see if audio and haptic feedback had an impact. 12 participants with little to no driving experience were recruited, five women and seven men. The study was an experiment of within-group design where half of the participants started driving with feedback, while the other half started driving without feedback and then they switched condition. Feedback during driving showed no significant effects on driving skill or safety. This could be due to the low sample size because even though there was no significant effect measured, there was a bigger amount of deviations in the no feedback test group. The results suggest that novice drivers don’t use audio haptic clues as part of their driving as much as experienced drivers do.

Nowadays surgery simulations are aiming to apply not just visual effects but forcefeedback as well. To carry out force feedback, haptic devices are utilized that are mostlycommercial products for general purposes. Some of the haptic device features are moreimportant than others in case of surgery simulator use. The precision of the output forcemagnitude is one such property. The specifications provided by haptic devicemanufacturers are lacking details on device characteristics, known to cause difficulties inplanning of accurate surgery simulations.This project shows the design of a testbed that is capable of measuring the precision ofoutput forces within the haptic devices’ workspace. With the testbed, a set ofmeasurements can be run on different haptic devices, giving as a result a betterknowledge of the utilized device. This knowledge aids the design of more precise andrealistic surgery simulations.

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Haptical technology is a field that is under constant development and that exists in many of today’s products, for example in VR-games and in the controls for vehicles. This kind of technology could in the same way simplify for disabled people by their being able to control a wheelchair using hand gestures. The purpose of this project is to research if a wheelchair can be controlled with hand gestures, and in that case, in which way that would be the most optimal. To answer the research questions in the project, a small scale prototype wheelchair was developed. This prototype is based on a microcontroller, Arduino, that is controlled by a sensor, IMU, that reads the angle of the user’s hand. Together, the components control two motors and steer the wheelchair. The result shows how hand gestures can steer the wheelchair forward, backward, left and right under constant speed, as well as making it stop. The prototype is able to follow the movements of the user’s hand, but reacts more slowly than would be desirable in a real situation. In spite of the fact that there are many different aspects to haptical steering of a wheelchair, this project shows that there is a large potential in implementing this kind of technology in an actual wheelchair. / Haptiskt styrning är en teknologi som utvecklas snabbt och inkorporeras i många av dagens produkter, till exempel i allt från VR-spel till styrning av fordon. På samma sätt skulle denna teknologi kunna underlätta för rörelsehindrade genom att erbjuda styrning av rullstol med hjälp av handrörelser. Syftet med detta projekt var därför att undersöka om en rullstol kan styras med handrörelser och i så fall vilket sätt som är optimalt. För att besvara rapportens frågeställning har framtagningen av en prototyp av en rullstol i liten skala gjorts. Denna är baserad på en mikrodator, Arduino, som styrs av en sensor, IMU, som mäter vinkeln på användarens hand. Med hjälp av dessa kan motorerna styras och rullstolen manövreras. Resultatet av rapporten har lett till ett förslag på hur handrörelser kan styra rullstolen framåt, bakåt, till vänster och till höger under konstant fart samt få den att stanna. Protypen följer gesterna som användarens hand visar, men reagerar långsammare än vad som vore önskvärt i verkligheten. Trots att många utvecklingsmöjligheter kvarstår för haptisk styrning av en rullstol, visar detta arbete att det finns stor potential i att implementera denna teknik med handrörelsestyrning i en verklig rullstol.

Telesurgery relies on fast and reliable data transmission between the surgeon and tele-operator side over lossy and delay constrained networks. Medical data involves audio, video, ECG and Force Feedback data. When these media streams are transmitted through best effort networks, the temporal information gets affected due to network constraints. Major network degradation is due to the Force Feedback device with rendering rate of 1 KHz, hence data is generated every millisecond. In our proposal we concentrate on improving the synchronization of force feedback device on varying networking conditions. Force feedback data is generated by operating a source (surgical) device which controls the movement of remote device. It has a great potential in improving telemedicine facilities, when included with the support of different multimedia services. The channel imposes delay and packet loss constraints for such devices which require unique solutions, unlike audio or video media, due to its high rendering rate. Current research supports Force Feedback in fiber optic communication, packet switched networks. However, such schemes are not feasible in supporting surgical telepresence system. While efforts are made to support force feedback media in wireless medium, few works have addressed delay synchronization and loss of data. There exists no previous work which has attempted to provide an efficient integrated solution where video and force feedback information have been supported by the same network. This thesis focuses in providing an integrated architecture that supports the force feedback data over a collaborative network and improves the data synchronization and packet loss prediction in the remote side over a varying network link. The goal will be to evaluate the support of such data types. We have implemented a Linear Packet Predictor Algorithm which predicts the missing packet value. Data generated from the source device are sent as UDP packets. UDP transmission is unreliable and hence we use an RTP over UDP to make it reliable. Each packet will have the current position of the device and force applied. We use a Microsoft Sidewinder Force Feedback joystick. The handle of the joystick is located at the center of the base. So we record the position of the device on both positive and negative axis moving in a two dimensional space. This device provides rotational movement and hence drastic change in position occurs within milliseconds. Once the packet arrives at the receiver side, the control unit checks for the sequence number of the packet. If continuity is missing then, the control unit passes the packet to the predictor algorithm which predicts the packet else it directly updates the packet to the Virtual Time Rendering Algorithm Another major issue is the delay jitter. On the source (server) side the intra time difference between two packets will be 1msec. But due to varying delay in the network the data packets arrive at the receiver with fluctuating intra time difference. In order to counter the delay jitter effect, we implement the Virtual Time Rendering algorithm which reads the time stamp value at which the packet was generated at the source and modifies the update time at the receiver side. In our work we do not control another device on the remote side, rather an applet which was developed using a Virtual Reality Markup Language in Matlab. Another challenge which is imposed when other multimedia is introduced with force feedback is the intra media synchronization. Real time video is captured from the applet side and given as feedback to the server side to improve the interactivity of the application. At every instant in time, different multimedia data produce data to be updated at the remote end. Since all the information are inter dependent with other media in time, efficient intra media synchronization is required. This thesis also focuses in providing an architecture which not only supports force feedback data but have a multiplexed model which allows an efficient transmission of all surgical information in real time. Each data occupies significant part of bandwidth in the network and the effect of multiplexing might affect the synchronization scheme of the force feedback device. Our architecture supports the efficient transmission of all types of multimedia information and also maintain the synchronization of the scheme. This method is unique with its methodical approach to support different multimedia information.

A quadrotor is an omnidirectional unmanned air vehicle that is suitable for indoor flight because of its ability to hover and maneuver in confined spaces. The remote operation of this type of vehicle is difficult due to a lack of sensory perception; typically, the view from the onboard camera is the only information transmitted to the pilot. This thesis proposes using force feedback exerted by the command input device on the hand of the pilot to assist in avoiding collisions while navigating in indoor environments. Five candidate algorithms are presented for calculating the forces to be felt by the pilot based on the quadrotor's position and velocity in the indoor environment. The candidates include a parametric algorithm based on the dynamics of the quadrotor, two time-to-impact algorithms, and two algorithms that employ virtual springs between the quadrotor and obstacles. A method of incorporating the position of the command input device to improve the usability and effectiveness of the algorithms is also presented. A framework for simulating the quadrotor dynamics, indoor environment, and force feedback algorithms is described. In the simulation, the pilot commands a simulated quadrotor, using a commercial haptic interface, as it flies in an indoor environment. The pilot receives force feedback cues as the quadrotor navigates around obstacles. Two methods of control were used for the simulation. In the first method, displacements of the haptic interface correspond to velocity commands to the quadrotor. In the second method, displacements of the input correspond to desired roll and pitch commands. Two user study experiments, one for each control method, were performed to compare the force feedback algorithms in simulation. The results of the velocity control experiment suggest that higher force levels help to avoid collisions and that the time to impact algorithm results in fewer collisions than having no force, but is not significantly better than the other algorithms. The results of the angle control experiment suggest that the time to impact algorithm is clearly the best in terms of hits and hit length and has no disadvantages compared to the other algorithms. Finally, to demonstrate the force feedback algorithms and software in a real-world environment, the system was interfaced with a physical quadrotor. The quadrotor system is described and the results of the tests are presented.

A haptic interface is a robotic force feedback device that provides a sense of touch to users of virtual reality simulations. This thesis presents a general method for the design optimization of parallel planar haptic devices based on maximizing the manipulability of the interface over its workspace. Manipulability is selected as the key design objective to ensure avoidance of singular configurations within the workspace and to maximize the interface's ability to generate feedback forces and torques in each direction in each handle location and orientation. The optimization approach developed in this thesis results in a set of candidate designs that are found by stepping the design parameters through the range of possible values, and testing the manipulability and other measures (including workspace area and space) at each location and orientation of the interface handle. To find the optimal design, a multi-objective approach is taken to generate a set of Pareto optimal designs. A smart Pareto filter is employed to yield a smaller set of designs representative of the full Pareto frontier. The most desirable design is chosen from this reduced set. The result is a general optimization method applicable to parallel haptic interfaces. The method is demonstrated on the design of a 3-RPR parallel planar interface.

BACKGROUND: Almost all fields of dentistry are very reliant on dentists’ well-developed dexterity and psychomotor skills. Simulation preclinical dental training is important for dental students to acquire preliminary manual dexterity before interacting with real patients. In the recent years, virtual reality specifically haptic simulations have drawn a lot of attention due to their multiple advantages including lack of the threat of spreading air-borne diseases. PURPOSE: The overall purpose of this study was to provide a review of the available dental haptic simulators in the market, and specific aim was to report the available evidence from the current scientific literature about the use and benefit of them during early preclinical pediatric dentistry training. METHODS: Information about Haptic VR simulators was obtained through manufacturers’ websites and current scientific literature. For the specific aim, the review is reported using the PRISMA-Scoping Review (ScR) guidelines and bibliographic databases such as PubMed, Cochrane library, Embase, and Dentistry and Oral Sciences Source. RESULTS: The systematic search identified 79 titles of which 14 full-text articles were selected for detailed review. Based on inclusion and exclusion criteria 4 studies were included in this review. CONCLUSION: Evaluation evidence from reviewed studies indicates the usefulness of the haptic simulators in preclinical pediatric dental training. The haptic simulators complement the existing phantom head simulators by offering different beneficial features. Further studies are necessary to evaluate the effectiveness of the simulators in pediatric dental training and to support the current availability of evidence.

The haptic device recreates the sense of touch by applying forces to the user. Since the device is “rendering” forces to emulate the physical interaction, the force control is essential for haptic devices. While a dedicated force/torque sensor can close the loop of force control, the additional equipment creates extra moving mass and inertia at the tool center point (TCP). Therefore, estimating the Cartesian force at the TCP has continuously been receiving attention over the past decades. The objective of this thesis project is to develop a real-time force estimation algorithm based on the proportional current-torque relationship with the dynamic modeling of the TAU haptic device. The algorithm can be further used for the force control of the device. The research questions of the thesis are: how to design and develop an algorithm for the TAU that used for Cartesian contact force estimation, how to set up the force estimation test bench and how to evaluate the results of the force estimation algorithm. In order to achieve the force estimation algorithm, a virtual environment is built to simulate the real-time haptic physics. Then an external force/torque sensor is installed at the TCP to get the measurement of the Cartesian force at the TCP. The force estimation algorithm calculates the Cartesian force at the TCP based on the current measurement of the DC motors at the six joints. The estimation result of the Cartesian force at the TCP is then compared with the force/torque sensor measurement to determine if the estimation algorithm is sufficiently accurate. The analysis of the estimation accuracy emphasizes the feasibility of Cartesian force estimation on the TAU haptic device. / En haptikenhet gör det möjligt att förmedla en känsla av kontakt i en virtuell värld genom att skapa krafter som motverkar en rörelse . Hur denna kraft skapas och kontrolleras är av stor vikt för att få den så verklighetstrogen som möjligt. Om man har en kraftsensor kan den användas till att utforma en kraftreglering med återkoppling, men på bekostnad av en ökad massa och tröghet vid användarens hand. Detta har medfört ett ökat intresse under de senaste åren för att på olika sätt försöka uppskatta den kraft som återkopplas till användaren utan att behöva en kraftsensor. Målet för detta examensarbete är att utveckla en algoritm för att uppskatta en kontaktkraft i realtid baserat på antagandet att motormomentet är proportionellt beroende av strömmen. Algoritmen kan sedan användas för att konstruera en sluten reglerloop med kraftåterkoppling för en haptisk enhet. Forskningsfrågorna som behandlas i detta examensarbete är;  hur kan vi utforma en algoritm för estimering av kontaktkrafter för haptikenheten TAU  hur kan vi utforma en experimentell försöksuppställning för mätning av de verkliga kontaktkrafterna från TAU vid kontakt.  hur kan vi använda resultaten från experimenten för utvärdering av algoritmen För testning och utvärdering av algoritmen har en virtuell värld skapats för att efterlikna en simuleringsmiljö som haptikenheten är tänkt att användas i. En kraftsensor har monterats under det verktyg som användaren håller i när enheten används när ett typiskt ingrepp ska övas i en simulator, t.ex. borrning i en tand. Vid experimenten beräknar algoritmen den uppskattade kontaktkraften som användaren känner baserat på den uppmätta strömmen för de sex motorer som aktiveras av kontakten. Dessa beräknade värden har sedan jämförts med de från kraftsensorn uppmätta för att avgör om algoritmen är tillräckligt noggrann. Analysen visar att noggrannheten är tillräckligt bra för att vara en lovande ansats till att användas för kraftuppskattning vid reglering av kontaktkraft för haptikenheten TAU.

Categorization is a complex decision-making process that requires observers to collect information about stimuli using their senses. While research on visual or auditory categorization is extensive, there has been little attention given to tactile categorization. Here we developed a paradigm for studying tactile categorization using 3D-printed objects. Furthermore, we derived a categorization model using Bayesian inference and tested its performance against human participants in our categorization task. This model accurately predicted participant performance in our task but consistently outperformed them, even after extending the learning period for our participants. Through theoretical exploration and simulations, we demonstrated that the presence of sensory measurement noise could account for this performance gap, which we determined was a present factor in participants undergoing our task through a follow-up experiment. Including measurement noise led to a better-fitting model that was able to match the performance of our participants much more closely. Overall, the work in this thesis provides evidence for the efficacy of a tactile categorization experimental paradigm, demonstrates that a Bayesian model is a good fit and predictor for human categorization performance, and underscores the importance of accounting for sensory measurement noise in categorization models. / Dissertation / Doctor of Philosophy (PhD) / The process of categorization is an essential part of our daily life as we encounter various things in the world. Here we explore a model that attempts to explain this process. This model is derived using Bayesian inference and was applied to human behavioural data in a categorization task. We found that the model accounted for most of the performance of our participants but consistently outperformed them. We conducted simulations to explore and demonstrate that this difference is primarily due to the presence of sensory noise in participants. Once we accounted for this noise, we found that our model predicted human performance even more accurately. The work in this thesis demonstrates that a Bayesian Categorization Model which accounts for sensory noise is a good fit and predictor for human performance on categorization tasks.