Combining Multi-touch Input and Device Movement for 3D Manipulations in Mobile Augmented Reality Environments

International audienceNowadays, handheld devices are capable of displaying augmented environments in which virtual content overlaps reality. To interact with these environments it is necessary to use a manipulation technique. The objective of a manipulation technique is to define how the input data modify the properties of the virtual objects. Current devices have multi-touch screens that can serve as input. Additionally, the position and rotation of the device can also be used as input creating both an opportunity and a design challenge. In this paper we compared three manipulation techniques which namely employ multi-touch, device position and a combination of both. A user evaluation on a docking task revealed that combining multi- touch and device movement yields the best task completion time and efficiency. Nevertheless, using only the device movement and orientation is more intuitive and performs worse only in large rotations

An Inertial Device-based User Interaction with Occlusion-free Object Handling in a Handheld Augmented Reality

Augmented Reality (AR) is a technology used to merge virtual objects with real environments in real-time. In AR, the interaction which occurs between the end-user and the AR system has always been the frequently discussed topic. In addition, handheld AR is a new approach in which it delivers enriched 3D virtual objects when a user looks through the device’s video camera. One of the most accepted handheld devices nowadays is the smartphones which are equipped with powerful processors and cameras for capturing still images and video with a range of sensors capable of tracking location, orientation and motion of the user. These modern smartphones offer a sophisticated platform for implementing handheld AR applications. However, handheld display provides interface with the interaction metaphors which are developed with head-mounted display attached along and it might restrict with hardware which is inappropriate for handheld. Therefore, this paper will discuss a proposed real-time inertial device-based interaction technique for 3D object manipulation. It also explains the methods used such for selection, holding, translation and rotation. It aims to improve the limitation in 3D object manipulation when a user can hold the device with both hands without requiring the need to stretch out one hand to manipulate the 3D object. This paper will also recap of previous works in the field of AR and handheld AR. Finally, the paper provides the experimental results to offer new metaphors to manipulate the 3D objects using handheld devices

Pre-define rotation amplitudes object rotation in handheld augmented reality

Interaction is one of the important topics to be discussed since it includes the interface where the end-user communicates with the augmented reality (AR) system. In handheld AR interface, the traditional interaction techniques are not suitable for some AR applications due to the different attributes of handheld devices that always refer to smartphones and tablets. Currently interaction techniques in handheld AR are known as touch-based technique, mid-air gesture-based technique and device-based technique that can led to a wide discussion in related research areas. However, this paper will focus to discover the device-based interaction technique because it has proven in the previous studies to be more suitable and robust in several aspects. A novel device-based 3D object rotation technique is proposed to solve the current problem in performing 3DOF rotation of 3D object. The goal is to produce a precise and faster 3D object rotation. Therefore, the determination of the rotation amplitudes per second is required before the fully implementation. This paper discusses the implementation in depth and provides a guideline for those who works in related to device-based interaction

Enhanced device-based 3D object manipulation technique for handheld mobile augmented reality

3D object manipulation is one of the most important tasks for handheld mobile Augmented Reality (AR) towards its practical potential, especially for realworld assembly support. In this context, techniques used to manipulate 3D object is an important research area. Therefore, this study developed an improved device based interaction technique within handheld mobile AR interfaces to solve the large range 3D object rotation problem as well as issues related to 3D object position and orientation deviations in manipulating 3D object. The research firstly enhanced the existing device-based 3D object rotation technique with an innovative control structure that utilizes the handheld mobile device tilting and skewing amplitudes to determine the rotation axes and directions of the 3D object. Whenever the device is tilted or skewed exceeding the threshold values of the amplitudes, the 3D object rotation will start continuously with a pre-defined angular speed per second to prevent over-rotation of the handheld mobile device. This over-rotation is a common occurrence when using the existing technique to perform large-range 3D object rotations. The problem of over-rotation of the handheld mobile device needs to be solved since it causes a 3D object registration error and a 3D object display issue where the 3D object does not appear consistent within the user’s range of view. Secondly, restructuring the existing device-based 3D object manipulation technique was done by separating the degrees of freedom (DOF) of the 3D object translation and rotation to prevent the 3D object position and orientation deviations caused by the DOF integration that utilizes the same control structure for both tasks. Next, an improved device-based interaction technique, with better performance on task completion time for 3D object rotation unilaterally and 3D object manipulation comprehensively within handheld mobile AR interfaces was developed. A pilot test was carried out before other main tests to determine several pre-defined values designed in the control structure of the proposed 3D object rotation technique. A series of 3D object rotation and manipulation tasks was designed and developed as separate experimental tasks to benchmark both the proposed 3D object rotation and manipulation techniques with existing ones on task completion time (s). Two different groups of participants aged 19-24 years old were selected for both experiments, with each group consisting sixteen participants. Each participant had to complete twelve trials, which came to a total 192 trials per experiment for all the participants. Repeated measure analysis was used to analyze the data. The results obtained have statistically proven that the developed 3D object rotation technique markedly outpaced existing technique with significant shorter task completion times of 2.04s shorter on easy tasks and 3.09s shorter on hard tasks after comparing the mean times upon all successful trials. On the other hand, for the failed trials, the 3D object rotation technique was 4.99% more accurate on easy tasks and 1.78% more accurate on hard tasks in comparison to the existing technique. Similar results were also extended to 3D object manipulation tasks with an overall 9.529s significant shorter task completion time of the proposed manipulation technique as compared to the existing technique. Based on the findings, an improved device-based interaction technique has been successfully developed to address the insufficient functionalities of the current technique