The experiment was conducted to evaluate the effectiveness of the MR concept on two gaming environments as part of the aims of thesis to develop an application prototype for telerobotics in remote mining equipment scenarios by utilising the features of gaming environments. Here, I determined task completion time, total commands sent and perceived level of difficulty as the outcome variables to indicate the user performance, with level of attention defined as a predictor variable. Analysis was conducted to compare outcome variables between the two groups categorized based on the predictor variable as well as between the interface, Sm and SL.
The results analysis on user performance in subsections 3.4.1 and 3.4.2 shows that paying a low level of attention to the interface and still being able to perform the task well suggests the participant was immersed in the interface and received a sufficient flow of information. This is supported by an argument by Chikszentmihalyi et al. [97], which defined immersion as a state of concentration so focused as to cause an absolute absorption in an activity. The user- friendliness of the interface and the enjoyment gained by the operator when interacting with the interface created a sufficiently immersive experience for the operator to perform the task well.
In task 1 where all required information is provided from both sources of information (3D model and video views), the experiment showed a statistically significant shorter task completion time and a lower perceived difficulty level for participants who paid a low level of attention to the interface. Since in task 1 ensuring that all the information needed to complete the task was sufficiently well modelled in the virtual world and available without referring to the video, the task could be undertaken by only paying attention to the video or to the model. My observations suggest that only occasional reference was made to the video which is in contrast to the real Rockbreaker interface [5] where the operator‘s attention was predominantly directed at the video and the model was mostly unused. This is in line with Adams [98] that mentioned the gaming environment is able to simulate reality inside the user‘s mind.
In contrast, in the task 2 where information about the rock position was only provided from the video views and not in the 3D model, which is usually the case in most telerobotics scenarios, the experiment did not demonstrate any association between the above variables. This might be due to an inadequate number of participants or other aspects of the gaming [98]. Based on this result, I suggest that other than being an immersive environment, a good interface should
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provide all required information to the operator. Building models that contain all the necessary information requires an excellent understanding of the task to identify the information that needs to be collected from a large number of measureable indicators and the methods for collecting the required information. This level of knowledge is required to fully automate the task which, if feasible to obtain, obviates the need for telerobotics.
This experiment showed that when users are immersed in the interface, they did not need to pay a high level of attention to the interface, including the display and how to operate the interface. Hence, the operators could be more focused on task accomplishment and thus increase their productivity. This experiment showed that the participants who paid a low level of attention to the interface perceived the task to be easier and were able to complete the task faster than those who paid a high level of attention to the interface.
In comparing user performance in both gaming environments, participants in using Sm environment perform better at the 95% confidence level than the SL environment. The main difference between the two model environments was manipulation of the model during movement was immediately reflected in the video overlay in the Sm environment, but in the SL environment the video overlay was updated only after the new location was specified. This was particularly useful when the viewpoint of the virtual camera was in a different direction to the actual camera, as participants found it difficult to understand how object movements would appear from a different viewing direction.
Another difference is that the participant is represented by an avatar (remote-person viewpoint) in the SL environment but not in the Sm environment. This experiment was not able to identify a significant difference in the task performance times suggesting that a ‗remote- person viewpoint‘ or ‗first-person viewpoint‘ did not have a large impact on the ease of usage. An avatar is not a hindrance to performance in this situation but is likely to be an advantage to interactions between two operators who must work together on a task. Other experiments have shown that using a three dimensional input device to manipulate a three dimensional model improved task performance, but the improvements will apply equally to either interface tested or even an interface using purely video feedback [65].
Based on the data analysis, I could say that a good interface will make the user feel immersed concentrating on the task flow without having to focus on the interface. This is in line with Fong et al [37] who stated that when an interface is well-designed, it becomes easy to use with minimal effort. On the contrary, when an interface is poorly crafted and difficult to understand, it becomes burdensome, limiting performance and making work tiresome. Hence
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the value of an interface is largely determined by how easily and effectively it allows the user to perform tasks.
This experiment also demonstrated that information from the 3D model was utilised by all participants to complete both tasks. This disproves my initial speculation that, since the operators were more familiar with the real view, they would tend to ignore the information provided by the 3D model. Supplying the required information from both sources of information (the video and 3D model) in gaming environments also showed that they can be used as telerobotic interfaces with minimal effort, and are enjoyable. This is in line with Jeger‘s conclusion [99] that understanding the factors that influence a user‘s enjoyment in an immersive environment allows improved technology such as gaming environments that are immersive.
In addition, the use of a combination of a virtual environment and the overlaying a virtual object (tip pointer) on the video did not show any negative effect on user performance. A prior experience in a gaming environment was not an essential factor for users to perform tasks in these telerobotics scenarios. The briefing and training prior to the tasks were sufficient in providing all the information required to perform the task well. This experiment demonstrated that the MR interface in gaming environments could be used as telerobotics user interfaces. It supported my proposition that using the MR concept in gaming environments was suitable as telerobotics user interface.