VR Medical Training

A importância do realismo na realidade virtual

Many philosophers debate the topic of reality, and the components that make up what we perceive to be “real”. Although an interesting mental exercise, we’re more interested in the practical applications of reality today, which is more accurately defined as “realism”.  

O realismo é definido como a representação de uma pessoa, coisa ou situação com precisão ou de uma forma que seja verdadeira. Neste artigo, buscamos entender em que grau essa definição de realismo pode ser conhecida em um ambiente totalmente simulado usando tecnologia de realidade virtual, e como isso impacta nosso mundo. 

To understand the importance of realism in virtual reality, we must first look to what the technology is trying to achieve— a simulation. A simulation is defined as an approximate imitation of the operation of a process or system. There’s an important distinction in that definition, which is to mimic the operation of something rather than just the thing itself. A simulation is a place of action; and that intent is what separates a simulation from a static learning tool such as text, video, or presentations. Ultimately, a simulation bridges the gap between knowledge and high performing actions. 

Traditionally, a simulation would be run “live” in a simulated physical space. History tells us that live simulations have been used as a learning tool for centuries, dating back to clay and stone models being used to understand the anatomy of a person. In more modern applications, simulations have been used to train students and professionals to assist in learning—for example a medical student may practice in a room dressed up as an operating theatre, or they could be taken a step further and practice on-site in an actual operating theatre (also known as in-situ or in-situation) which was considered to have a higher degree of realism. The objects within that environment also benefit from being as real as possible, which could mean the difference between using mannequins or a paid actor to simulate a patient.

Simulations have more recently found a new environment in which to model themselves, known as “virtual”, where one would experience the imitation synthetically. Thanks to computer technology, virtual simulations have been able to imitate an operation without the need of costly physical environments and the challenging logistics of getting people to them. Virtual Reality (VR) specifically refers to synthetic imitations presented inside of a special headset, which enhances the immersion of a synthetic environment further by assuming the user’s entire field of vision rather than just on a two dimensional screen. 

Os fones de ouvido de realidade virtual têm sido usados comercialmente por organizações como a NASA há décadas e, conforme o custo de produção diminuiu, a tecnologia se tornou mais viável para compra pelo consumidor. Além disso, o poder de processamento do hardware usado para rodar fones de ouvido de realidade virtual levou a simulações mais realistas. No entanto, até que ponto o realismo afeta a eficácia de uma simulação, especialmente em situações de treinamento? 

To understand the efficacy of realism, we must look at a key variable that defines the perceived realism—fidelity.  Fidelity refers to how closely a simulation imitates or amplifies reality. The overall goal of high-fidelity simulations is to improve the performance of an action, or what a person actually does (rather than thinks). In 1990, Miller (1990) indicated that this action is built upon a person’s knowledge, competence, and performance. 

Generally speaking, a low fidelity simulation is good for building upon knowledge – it won’t feel real, but it will outline the basics and theory well enough. Medium fidelity is used to build competence through greater interaction, then high fidelity is where high performance action occurs. This model of traditional Fidelity can be viewed as a pyramid. Without the base level of knowledge, you can’t reach the top level of action. As you begin to improve your knowledge, competence, and performance, the action level of fidelity in a simulated environment increases too, agnostic of how the environment is actually presented. For example, the fidelity of a commercial flight simulator will be different for someone with no knowledge of aviation in comparison to someone who has spent years studying the theory. How will the person with little knowledge be able to know if the simulation is high-fidelity or not, if they don’t understand what to look for? Therefore, to some extent the concept of fidelity is subjective. 

This can be understood at a deeper level by examining the different components that make up fidelity, over and above the person experiencing it. At a conceptual level, the scenario at hand needs to make sense. For example, you would expect a flight simulator to have a high degree of conceptual fidelity if it flies through the air, rather than through Walmart. Physically, the simulation needs to reflect the actual physical properties of the real environment. The flight simulator wouldn’t have a high degree of physical fidelity if it used carrots for the levers. Emotionally, the simulation should try to capture the same feelings one would expect in the real environment. For example, a simulated emergency in the cockpit of a plane should feel naturally urgent to deal with, rather than casual and boring. New technology such as heart-rate monitors built into wearable devices have made it easier to test for emotional response, helping simulators find better ways to increase the degree of emotional fidelity. 

No entanto, esse nível de compreensão vai um passo mais fundo novamente quando visto no contexto de simulações de realidade virtual. Há uma consideração importante quando se trata de medir a fidelidade em um ambiente de realidade virtual, especialmente no que diz respeito a simulações de treinamento. Stone (2011) encontrou o equívoco de que os avanços tecnológicos levam a melhores ambientes de treinamento. Stone e sua equipe de tecnologias de interface humana descobriram que isso é muito menos importante do que o conceito de design centrado no ser humano. Quando o objetivo é maximizar a transferência de tarefas, conhecimentos, habilidades e comportamentos simulados para aplicações do mundo real; a fidelidade psicológica é a chave.  

A fidelidade psicológica é o grau em que as tarefas simuladas podem reproduzir os comportamentos necessários às aplicações do mundo real. Isso, até certo ponto, combina as idéias tradicionais de fidelidade conceitual, física e emocional, conforme descrito; embora normalmente alguém olhe para a fidelidade neste contexto como uma combinação de fidelidade física e psicológica.

It is through this definition that it also becomes obvious that pure technological advances aren’t a large part of that equation, but rather the technical advances make it more accessible and viable. The major drawback of new interfaces such as virtual reality is that of a human experience nature. Think back to the first few years of websites—every site was completely different with walls of text, hidden links, strange navigations, and unique layouts. It wasn’t until many years later that a standardized experience began to take shape that was more natural to the user, taking advantage of modern design principles, content structures, and human behaviour to deliver a seamless experience. Virtual reality is still in the early stages of exploring the best user interface, however it is far more complicated due to the additional dimension. It’s one thing to master the interface of a 2D screen with basic inputs, but quite another in a 3D environment. 

Stone quebrou ainda mais o conceito de fidelidade para simulações de realidade virtual, como segue:

  • Context Fidelity should seek to represent an appropriate background of sensory and behavioral detail—think background extras on a movie set. They don’t get in the way, but they add to the context of the scene.
  • Fidelidade de tecnologia interativa é o grau em que os controles de entrada (pense em fones de ouvido e controles manuais) representam as interfaces da vida real. 
  • A hipofidelidade e a hiperfidelidade medem a importância de poucos ou muitos detalhes sensoriais, detalhes comportamentais e sistemas de interação

Interestingly, many end-users already have a concept of fidelity in their head before entering a training simulation, a baseline of expectations based on what they’ve seen in other applications such as gaming and military applications. Now the complex web of what makes up a “high fidelity” training simulation begins to reveal itself. We know that at the highest level, the end-user needs a basic knowledge of the system and also a certain level of competence before reaching high-performance actions. However, simulations run in virtual reality require a balance of contextual sensory and behavioural details alongside realistic input characteristics; while catering to the potential expectation gap a user may have before entering the simulation. This is all impacted further by the challenges virtual reality face with regards to seamless interfaces that are not yet standardized or widely understood by users.

So, if a virtual reality simulation can have a high degree of psychological and physical fidelity, then it can be considered to be more realistic—assuming the user already has some knowledge and competence to be able to perceive it that way to begin with. However, this is all qualified by the ability for humans to actually use it, an idea often called human-centered design.

Agora que entendemos a composição mais ampla do realismo em uma simulação, podemos usá-lo em nossa vantagem em aplicativos de realidade virtual. Por exemplo, a plataforma de treinamento cirúrgico PrecisionOS foi projetada para fazer uso de modernos mecanismos gráficos para imitar o ambiente físico, incluindo detalhes sensoriais e comportamentais, como ferramentas, iluminação e maquinários com alto grau de fidelidade física. O paciente na mesa cirúrgica é configurado para apresentar os sintomas que requerem um determinado procedimento, garantindo que a representação seja balanceada para evitar a hipofidelidade ou a hiperfidelidade. Os controladores manuais são configurados para se parecerem mais com as ferramentas cirúrgicas comuns de um procedimento, visando uma maior fidelidade da tecnologia interativa. Por fim, o procedimento simulado é guiado em tempo real com feedback e orientação, tanto visualmente quanto via áudio, para simular o ambiente psicológico como se estivesse treinando com um cirurgião sênior. 

Students or staff have already completed many years of medical school which includes traditional learning tools and simulations, so they have a high degree of knowledge and competence. Therefore, a realistic virtual environment can help them train for advanced skillsets and enhanced confidence without having to practice on real patients—which can be both costly to the trainee, the patient, their family, and the hospital; not to mention challenging to find appropriate training patients and matching them with trainees on a repeating basis. Em um nível mais amplo, isso significa, em última análise, melhores cirurgiões e uma maior taxa de sucesso para os pacientes. 

The future of realism in virtual reality looks promising. Already, we’ve seen physical feedback in VR hand controllers which has been proven to enhance the perception of interactive technology fidelity (Hoffman, 2011), and this technology is expanding to full haptic-feedback suits. As other fields of technology such as biotech begin to crossover with virtual reality, we’ll see even more integration and immersion. For example, the user may be able to control their virtual environment using just their thoughts, or be able to connect sensors directly to nerve endings for realistic feedback. 

As the technology improves, so too does the perceived realism of our virtual environments—and as we’ve seen, this will further engage our world’s future students and professionals to perform at a higher level. The result in many years’ time will be a safer, more productive world to live in, and we can’t wait to stake our hand in the efforts. 

Fontes: 

https://pdfs.semanticscholar.org/1bba/11bf001e17ec4643f63943fb1dffef008299.pdf
http://nursingeducation.lww.com/blog.entry.html/2018/09/19/increasing_fidelity-zEj0.html
https://www.docketalarm.com/cases/International_Trade_Commission/337-770/Certain_Video_Game_Systems_and_Wireless_Controller_and_Components_Thereof/446916/49/