Brian F. Goldiez

A Survey of Commercial & Open Source Unmanned Vehicle Simulators

This report presents a survey of computer based simulators for unmanned vehicles. The simulators examined cover a wide spectrum of vehicles including unmanned aerial vehicles, both full scale and micro size; unmanned surface and subsurface vehicles; and unmanned ground vehicles. The majority of simulators use simple numerical simulation and simplistic visualization using custom OpenGL code. An emerging trend is to used modified commercial game engines for physical simulation and visualization. The game engines that are commercially available today are capable of physical simulations providing basic physical properties and interactions between objects. Newer and/or specialized engines such as the flight simulator X-Plane or Ageia PhysX and Havok physics engines, are capable of simulating more complex physical interactions between objects. Researchers in need of a simulator have a choice of using game engines or available open source and commercially available simulators, allowing resources to be focused on research instead of building a new simulator. We conclude that it is no longer necessary to build a new simulator from scratch.

Predicting presence: Constructing the Tendency toward Presence Inventory

We used a rational-empirical approach to construct the Tendency toward Presence Inventory (TPI), constructing scales to measure the individual difference human factors hypothesized to predict a persons tendency to experience the cognitive state of presence. The initial pool of 105 items was administered to 499 undergraduate psychology students at a university in the southeastern United States in order to empirically validate the underlying factor structure associated with this tendency. Six factors were derived, resembling the original conceptual model. Construct validity and reliability evidence are presented. Future empirical work is needed to explore the criterion and predictive validities of the factors constituting this inventory.

Virtual Experience Test: A virtual environment evaluation questionnaire

We present the development and evaluation of the Virtual Experience Test (VET). The VET is a survey instrument used to measure holistic virtual environment experiences based upon the five dimensions of experiential design: sensory, cognitive, affective, active, and relational. Experiential Design (ED) is a holistic approach to enhance presence in virtual environments that goes beyond existing presence theory (i.e. a focus on the sensory aspects of VE experiences) to include affective and cognitive factors. To evaluate the VET, 62 participants played the commercial video game Mirrors Edge. After gameplay both the VET and the ITC-Sense of Presence Inventory (ITC-SOPI) were administered. A principal component analysis was performed on the VET and it was determined that the actual question clustering coincided with the proposed dimensions of experiential design. Furthermore, scores from the VET were shown to have a significant relationship with presence scores on the ITC-SOPI. The results of this research produced a validated measure of holistic experience that could be used to evaluate virtual environments. Furthermore, our experiment indicates that virtual environments utilizing holistic designs can result in significantly higher presence.

Human-aware robot motion planning with velocity constraints

This paper addresses the issue of how high-speed robots may move among humans such that the robots complete their tasks efficiently while the humans in the environment feel safe and comfortable. It describes the Segway robotic platform used for this research and then discusses the three primary research areas needed to develop the human-aware motion planner. First, it is necessary to conduct experiments with humans to develop human aware velocity constraints as a function of the distance of the robot from a human. Next, these velocity constraints must be used to plan the robot motion in real time. Finally, practical implementation of this motion planner requires the ability to robustly detect humans using the available vision sensors. The approach taken to each of these problems is described in this paper along with preliminary results.

History of networked simulations

Networks of simulators are a rapidly advancing technology and provide new utility for real time simulators. Simulator networking will enhance the use of simulation for training, product development, test, analysis, and creation of virtual environments. The current terminology for networks of simulators is called Distributed Interactive Simulation or DIS. DIS consists of descriptions of the protocols, the underlying network, and the architecture for connecting individual simulators. It also supports limited connectivity between real time simulators, live equipment, and discrete event simulations. However, DIS is only the current manifestation of simulator networking. One can look to processes pushing advances in simulator design, computer technology, communications technology, and innovative requirements development as key factors influencing simulator networking. These processes have been on-going for nearly thirty years. It is important to reflect on these development efforts to chart the future course for networked simulators.

A robot simulator classification system for HRI

This paper presents a classification system for computer-based robot simulators that is based on the FAA guidelines for aircraft simulators. Low fidelity computer simulation has been used extensively for testing artificial intelligence and control algorithms for robotic systems. Until recently operator training using simulators has been impractical due to the cost of the computer systems necessary to simulate robot operation with high fidelity. The rapid increase in the power of desktop computers over the last decade has led to cheap, high fidelity vehicle simulation. A review of the literature shows that there are many robot simulators in use with a variety of features and fidelity levels. There has been no prior work attempting to classify the functionality of these robot simulators.

Collaboration on the edge of chaos

Research at the Institute for Simulation and Training has uncovered the curious fact that human psychomotor activity is mathematically chaotic at high performance levels. This chaotic behavior manifests both when humans are acting alone and when they are interacting with semi-autonomous devices in real and simulated environments. Other studies have reported that robots alone also exhibit mathematically chaotic behavior. This has led to the working hypothesis that chaotic measures such as the Lyapunov exponent can be used to quantify performance levels in human robot collaboration in an objective way. Experiments are in progress to help better understand and quantify the occurrence of chaotic behavior in human robot collaboration. The expectation is that Lyapunov exponent and other chaos-related measures will prove useful as diagnostic tools for both operational tasks and for training. Our goal is to investigate using overt actions (navigational inputs now and possibly other things like facial expression in the future) for capturing the Lyapunov exponent in real time and as a function that varies over time in response to behaviors. The challenge is to determine which factor to measure for a specific type of task. Additional research will be needed to link task to human psychophysical activity and to robot activity as well as the ability to transition between data modes as tasks change.

Software infrastructure for multi-modal virtual environments

Virtual environment systems, especially those supporting multi-modal interactions require a robust and flexible software infrastructure that supports a wide range of devices, interaction techniques, and target applications. In addition to interactivity needs, a key factor of robustness of the software is the minimization of latency and more importantly, reduction of jitter (the variability of latency). This paper presents a flexible software infrastructure that has demonstrated robustness in initial prototyping. The infrastructure, based on the VESS Libraries from the University of Central Florida, simplifies the task of creating multi-modal virtual environments. Our extensions to VESS include numerous features to support new input and output devices for new sensory modalities and interaction techniques, as well as some control over latency and jitter.

Methodology for quantitative assessment of combat casualty care

Evaluating proficiency in simulation-based combat casualty training includes the assessment of hands-on training with mannequins through instructor observation. The evaluation process is error-prone due to high student–instructor ratios as well as the subjective nature of the evaluation process. Other logistical inconsistencies, such as the short amount of time to observe individual student performance, can lessen training effectiveness as well. The simulation-based methodology described in this article addresses these challenges by way of quantitative assessment of training effectiveness in combat casualty training. The methodology discusses adaptation of Lempel–Ziv (LZ) complexity indexing to quantify psychomotor activity that is otherwise only subjectively estimated by an instructor. LZ indexing has been successfully used to assess proficiency in related studies of simulation-based training conducted by Bann et al. at the Imperial College of Science Technology and Medicine in London, and more recently by Watson at the University of North Carolina at Chapel Hill. This type of analysis has been applied to using simulation as a tool to assess not only mastery of a task, but as a method to assess whether a particular simulator and training approach actually works. Data have been gathered from nearly 100 military combat medic trainees at Joint Base Lewis McChord Medical Simulation Training Center. Participant hand-acceleration data from an emergency surgical cricothyrotomy reveals a statistically significant difference in ability between expertise levels. The higher the LZ scores and self-reported expertise level, the better the participant performed. The results show that when presented with demographic and video performance-based data, it is possible to gauge experience by applying LZ scoring to motion data. The methodology provides an objective measure that complements the subjective component of simulation-based cricothyrotomy training assessments. Further study is needed to determine whether this methodology would provide similar assessment advantages in other medical training in which speed and accuracy would be significant factors in determining procedural expertise.

Modelling and Simulation to Support the Counter Drone Operations (NMSG-154)

The proliferation of Low, Slow and Small (LSS) flying platforms brings with it a new and rapidly increasing threat for national defence and security agencies. Thus, defence systems must be designed to face such threats. Modern operational readiness bases on proper personnel training that is performed on high fidelity simulators. The aim of the MSG.154 is to take into account the variety of the commercially available LSS aerial vehicles and to define LSS models from different points of view. This is carried out in order to make such models available for analysis and design aspects that are applied to Counter LSS systems, for both detection and neutralization, and for operational training. Moreover, their ability to cross correlate friendly nation LSS capabilities among member nations and to extend LSS to existing categorizations is useful beneficial.