Dual Loop Rider Control of a Dynamic Motorcycle Riding Simulator

Compared to the automotive industry, the use of simulators in the motorcycle domain is negligible as for their lack of usability and accessibility. According to the state-of-the-art, it is e.g. not possible for motorcyclists to intuitively control a high-fidelity dynamic motorcycle riding simulator when getting in contact with it for the first time. There are four main reasons for the insufficient simulation quality of dynamic motorcycle riding simulators: ▪ The instability of single-track vehicles at low speed, ▪ The steering force-feedback with highly velocity-dependent behavior, ▪ Motion-simulation (high dynamics, roll angle, direct contact to the environment), ▪ The specific influence of the rider to vehicle dynamics (incl. rider motion). The last bullet point is peculiar for motorcycles and dynamic motorcycle riding simulators in comparison with other vehicle simulators, as motorcycles are significantly affected in their dynamics by the rider’s body motion. However, up until today, almost no special emphasis has been put on the consideration of rider motion on dynamic motorcycle riding simulators. In this thesis, a motorcycle riding simulator is designed, constructed and put into operation. The focus here is attaching a real rider to a virtual motorcycle. Based on a commercially available multi-body-simulation model, a simulator architecture is designed, that allows to control the virtual motorcycle not only by steering, but by rider leaning as well. This is realized by determining the so-called rider induced roll torque, that allows a holistic measurement of the apparent coupling forces between rider and simulator mockup. Performance measures and study concepts are developed that allow to rate the system. In expert and participant studies, the influence of the system on the riding behavior of the simulator is investigated. It is shown that the rider motion determination allows realistic control inputs and has a positive effect on the stabilization at various velocities. The feedback of the rider induced roll torque to the virtual dynamics model allows study participants to control the virtual motorcycle more intuitively. The vehicle states during cornering are affected as expected from real riding. First results indicate that it becomes easier for naïve study participants to access the simulator in first-contact scenarios. The achieved improvements regarding the rideability of the simulator however do not suffice to overcome the abovementioned challenges to a degree that allows for a completely intuitive interaction with the simulator throughout the whole dynamic range

Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 171

This bibliography lists 186 reports, articles, and other documents introduced into the NASA scientific and technical information system in August 1977

The effects of physical activity on balance and postural control in people with down syndrome

People with Down Syndrome (DS) often have impaired balance and postural control and result as less active than their peers, that can lead to reduced quality of life and movement skills. Effects of physical activity may be important in preventing falling risk and health consequences in people with DS. In this context, we conducted a literature search of original articles, published between January 2010 and January 2020, on the effects of physical activity on balance and postural control in people with DS. We found 16 articles from almost all continents, investigating the effects of different types of physical activity on static and dynamic balance and postural control. The included studies reported improvements in both static and dynamic balance with exercise programmes lasting at least 6 weeks and containing strength, aerobic and sensorimotor training. However, the most suitable type of physical activity for people with DS is not clear. In conclusion, physical activity is highly recommendable in people with DS, to improve their balance and prevent falling risk

Posture Affects Affordance Perception of Reachability in Virtual Reality

Tasks such as standing and reaching require differing levels of postural stability. Postural equilibrium is necessary to perceive the location of objects (Lee, Pacheco, & Newell, 2018). Visual perception of whether an object is within reach was investigated while standing upright. Participants viewed a 3D virtual reality (VR) environment with a stimulus object (red ball) placed at different egocentric distances. Participants made affordance judgements while in a standard stance condition as well as two separate active balance conditions (yoga tree pose, and toe-to-heel pose). Feedback on accuracy was not provided, and participants were not allowed to attempt to reach. Response time, affordance judgments (reachable, not reachable), and head movements were recorded on each trial. Consistent with recent research on reaching ability (Weast & Proffitt, 2018), the perceived action boundary occurred around 120% of arm length, indicating overestimation of perceived reaching ability. Response times increased with distance, and were shortest for the most difficult yoga tree pose. Head movement amplitude increased with increases in balance demands. Surprisingly, the coefficient of variation was comparable in the two poses that had increased balance requirements, and was more extreme in a less constrained, ostensibly easier pose for the shortest and longest distances. More complex descriptors of postural sway (i.e. multifractality) were predictive of perception while in the tree pose and the toe-to-heel pose, as compared to control stance. This demonstrates that standard measures of central tendency are not sufficient for describing multiscale interactions of postural dynamics in functional tasks

The Effects of Finger-Walking in Place (FWIP) on Spatial Knowledge Acquisition in Virtual Environments

Spatial knowledge, necessary for efficient navigation, comprises route knowledge (memory of landmarks along a route) and survey knowledge (overall representation like a map). Virtual environments (VEs) have been suggested as a power tool for understanding some issues associated with human navigation, such as spatial knowledge acquisition. The Finger-Walking-in-Place (FWIP) interaction technique is a locomotion technique for navigation tasks in immersive virtual environments (IVEs). The FWIP was designed to map a human’s embodied ability overlearned by natural walking for navigation, to finger-based interaction technique. Its implementation on Lemur and iPhone/iPod Touch devices was evaluated in our previous studies. In this paper, we present a comparative study of the joystick’s flying technique versus the FWIP. Our experiment results show that the FWIP results in better performance than the joystick’s flying for route knowledge acquisition in our maze navigation tasks

Brain-controlled cycling system for rehabilitation following paraplegia with delay-time prediction

Objective: Robotic rehabilitation systems have been investigated to assist with motor dysfunction recovery in patients with lower-extremity paralysis caused by central nervous system lesions. These systems are intended to provide appropriate sensory feedback associated with locomotion. Appropriate feedback is thought to cause synchronous neuron firing, resulting in the recovery of function. Approach: In this study, we designed and evaluated an ergometric cycling wheelchair, with a brain-machine interface (BMI), that can force the legs to move by including normal stepping speeds and quick responses. Experiments were conducted in five healthy subjects and one patient with spinal cord injury (SCI), who experienced the complete paralysis of the lower limbs. Event-related desynchronization (ERD) in the β band (18‐28 Hz) was used to detect lower-limb motor images. Main results: An ergometer-based BMI system was able to safely and easily force patients to perform leg movements, at a rate of approximately 1.6 seconds/step (19 rpm), with an online accuracy rate of 73.1% for the SCI participant. Mean detection time from the cue to pedaling onset was 0.83±0.31 s Significance: This system can easily and safely maintain a normal walking speed during the experiment and be designed to accommodate the expected delay between the intentional onset and physical movement, to achieve rehabilitation effects for each participant. Similar BMI systems, implemented with rehabilitation systems, may be applicable to a wide range of patients

Knowing How: An Empirical, Functionalist Approach

Only very recently has the subject of knowledge how and its relation to propositional knowledge, or knowledge that, been given much attention by philosophers. In recent debates on the subject, positions tend to divide around the question: is knowledge how (KH) reducible to, or a kind of, knowledge that (KT), or are they fundamentally distinct categories of knowledge? I argue for the latter view, and I base my argument in the claim that KH and KT serve fundamentally different functional roles - specifically, KT is representational, while KH is practical. I develop my positive, functionalist account of KH in Chapter 6. Earlier chapters deal with background and methodological issues. In Chapter 1, I consider why philosophers, until recently, have tended to ignore the study of KH and have focused almost exclusively on KT. I argue that the omission is due to unexamined, tacit assumptions about the functional role knowledge should play. In Chapter 2, I argue for an empirical approach to the debate, and develop a folk theory of KH to use as a starting point for the investigation. In Chapters 3 and 4, I consider specific empirical domains - neuroscience and experimental psychology - and examine how they might inform the KH/KT debate. In Chapter 5, I critically consider an account of KH put forward by Jason Stanley and Timothy Williamson in a 2001 article, Knowing How, since it is the most prominent view opposed to my conclusion. Ultimately, I conclude that the preponderance of evidence supports the claim that the two kinds of knowledge are fundamentally distinct categories of knowledge, and that my functionalist account of KH provides the best explanation for this distinction