Data-based dynamic haptic interaction model with deformable 3D objects

The data-based modeling of the haptic interaction simulation is a growing trend in research. These techniques offer a quick alternative to parametric modeling of the simulation. So far, most of the use of the data-based techniques was applied to static simulations. This paper introduces how to use data-based model in dynamic simulations. This ensures realistic behavior and produce results that are very close to parametric modeling. The results show that a quick and accurate response can be achieved using the proposed methods.

Function-based single and dual point haptic interaction in Cyberworlds

Polygon and point based models dominate virtual reality. These models also affect haptic rendering algorithms, which are often based on collision with polygons. With application to dual point haptic devices for operations like grasping, complex polygon and point based models will make the collision detection procedure slow. This results in the system not able to achieve interactivity for force rendering. To solve this issue, we use mathematical functions to define and implement geometry (curves, surfaces and solid objects), visual appearance (3D colours and geometric textures) and various tangible physical properties (elasticity, friction, viscosity, and force fields). The function definitions are given as analytical formulas (explicit, implicit and parametric), function scripts and procedures. We proposed an algorithm for haptic rendering of virtual scenes including mutually penetrating objects with different sizes and arbitrary location of the observer without a prior knowledge of the scene to be rendered. The algorithm is based on casting multiple haptic rendering rays from the Haptic Interaction Point (HIP), and it builds a stack to keep track on all colliding objects with the HIP. The algorithm uses collision detection based on implicit function representation of the object surfaces. The proposed approach allows us to be flexible when choosing the actual rendering platform, while it can also be easily adopted for dual point haptic collision detection as well as force and torque rendering. The function-defined objects and parts constituting them can be used together with other common definitions of virtual objects such as polygon meshes, point sets, voxel volumes, etc. We implemented an extension of X3D and VRML as well as several standalone application examples to validate the proposed methodology. Experiments show that our concern about fast, accurate rendering as well as compact representation could be fulfilled in various application scenarios and on both single and dual point haptic devices.

Haptic microrobotic intracellular injection assistance using virtual fixtures

In manual cell injection the operator relies completely on visual information for task feedback and is subject to extended training times as well as poor success rates and repeatability. From this perspective, enhancing human-in-the-loop intracellular injection through haptic interaction offers significant benefits. This paper outlines two haptic virtual fixtures aiming to assist the human operator while performing cell injection. The first haptic virtual fixture is a parabolic force field designed to assist the operator in guiding the micropipette's tip to a desired penetration point on the cell's surface. The second is a planar virtual fixture which attempts to assist the operator from moving the micropipette's tip beyond the deposition target location inside the cell. Preliminary results demonstrate the operation of the haptically assisted microrobotic cell injection system.

Enabling multi-point haptic grasping in virtual environments

Haptic interaction has received increasing research interest in recent years. Currently, most commercially available haptic devices provide the user with a single point of interaction. Multi-point haptic devices present a logical progression in device design and enable the operator to experience a far wider range of haptic interactions, particularly the ability to grasp via multiple fingers. This is highly desirable for various haptically enabled applications including virtual training, telesurgery and telemanipulation. This paper presents a gripper attachment which utilises two low-cost commercially available haptic devices to facilitate multi-point haptic grasping. It provides the ability to render forces to the user's fingers independently and using Phantom Omni haptic devices offers several benefits over more complex approaches such as low-cost, reliability, and ease of programming. The workspace of the gripper attachment is considered and in order to haptically render the desired forces to the user's fingers, kinematic analysis is discussed and necessary formulations presented. The integrated multi-point haptic platform is presented and exploration of a virtual environment using CHAI 3D is demonstrated.

Virtual haptic cell model for operator training

Microrobotic cell injection is an area of growing research interest. Typically, operators rely on visual feedback to perceive the microscale environment and are subject to lengthy training times and low success rates. Haptic interaction offers the ability to utilise the operator’s haptic modality and to enhance operator performance. Our earlier work presented a haptically enabled system for assisting the operator with certain aspects of the cell injection task. The system aimed to enhance the operator’s controllability of the micropipette through a logical mapping between the haptic device and microrobot, as well as introducing virtual fixtures for haptic guidance. The system was also designed in such a way that given the availability of appropriate force sensors, haptic display of the cell penetration force is straightforward. This work presents our progress towards a virtual replication of the system, aimed at facilitating offline operator training. It is suggested that operators can use the virtual system to train offline and later transfer their skills to the physical system. In order to achieve the necessary representation of the cell within the virtual system, methods based on a particle-based cell model are utilised. In addition to providing the necessary visual representation, the cell model provides the ability to estimate cell penetration forces and haptically display them to the operator. Two different approaches to achieving the virtual system are discussed.

A haptic platform to enable fingertip grasping and manipulation

Haptic technologies allow human users to haptically interact with virtual environments. Haptics has been employed in many application domains including operator training, virtual exploration and teleoperation. Currently, most commercially available haptic devices focus on a single point of haptic interaction. While single-point haptics have been successfully employed in many applications, they remain limited to particular types of haptic interaction. Multi-point haptic devices are a logical progression and facilitate a far wider range of interactions including object grasping, multi-finger object manipulation and size discrimination. The ability to effectively achieve such interactions offers significant benefits for many applications including virtual training, telesurgery and telemanipulation. In such applications, the ability to use multi-point haptic interactions can provide far more effective user interaction as well improved perception of the virtual environment.

Function-based approach to mixed haptic effects rendering

Commonly, surface and solid haptic effects are defined in such a way that they hardly can be rendered together. We propose a method for defining mixed haptic effects including surface, solid, and force fields. These haptic effects can be applied to virtual scenes containing various objects, including polygon meshes, point clouds, impostors, and layered textures, voxel models as well as function-based shapes. Accordingly, we propose a way how to identify location of the haptic tool in such virtual scenes as well as consistently and seamlessly determine haptic effects when the haptic tool moves in the scenes with objects having different sizes, locations, and mutual penetrations. To provide for an efficient and flexible rendering of haptic effects, we propose to concurrently use explicit, implicit and parametric functions, and algorithmic procedures.

Multipoint haptic mediator interface for robotic teleoperation

Despite recent advances in artificial intelligence and autonomous robotics, teleoperation can provide distinct benefits in applications requiring real-time human judgement and intuition. However, as robotic systems are increasingly becoming sophisticated and are performing more complex tasks, realizing these benefits requires new approaches to teleoperation. This paper introduces a novel haptic mediator interface for teleoperating mobile robotic platforms that have a variety of manipulators and functions. Identical master-slave bilateral teleoperation of the robotic manipulators is achieved by representing them in virtual reality and by allowing the operator to interact with them using a multipoint haptic device. The operator is also able to command motions to the mobile platform by using a novel haptic interaction metaphor rather than a separate dedicated input device. The presented interaction techniques enable the operator to perform a wide range of control functions and achieve functionality similar to that of conventional teleoperation schemes that use a single haptic interface. The mediator interface is presented, and important considerations such as workspace mapping and scaling are discussed. © 2015 IEEE.

Multipoint haptic guidance for micrograsping systems

The ability to perform accurate micromanipulation offers wide-reaching benefits and is of increasing interest to researchers. Recent research into microgripper, microtweezer, and microforcep systems contributes toward accurate micrograsping and manipulation. Despite these efforts, achieving adequate operator control remains a distinct research challenge. Haptic interfaces interact with the human's haptic modality and offer the ability to enhance the operator's controllability of micromanipulation systems. Our previous work introduced single-point haptic guidance to assist the operator during intracellular microinjection. This paper extends the approach to propose multipoint haptic guidance for micrograsping tasks. Accurate micrograsping is valuable in many applications, including microassembly and biomanipulation. A multipoint haptic gripper facilitates haptic interaction, and haptic guidance assists the operator in controlling systems suitable for micrograsping. Force fields are used to guide the operator to suitable grasp points on micrometer-sized objects and consist of attractive and repulsive forces. The ability of the force field to effectively assist the operator in grasping the cell is evaluated using a virtual environment. Evaluation results demonstrate the ability of the approach to significantly reduce participants' average grasping error.

Grasping virtual objects with multi-point haptics

The majority of commercially available haptic devices offer a single point of haptic interaction. These devices are limited when it is desirable to grasp with multiple fingers in applications including virtual training, telesurgery and telemanipulation. Multipoint haptic devices serve to facilitate a greater range of interactions. This paper presents a gripper attachment to enable multi-point haptic grasping in virtual environments. The approach employs two Phantom Omni haptic devices to independently render forces to the user's thumb and other fingers. Compared with more complex approaches to multi-point haptics, this approach provides a number of advantages including low-cost, reliability and ease of programming. The ability of the integrated multi-point haptic platform to interact within a CHAI 3D virtual environment is also presented.

Integrating kinect and haptics for interactive STEM education in local and distributed environments

Skill shortage is a realistic social problem that Australia is currently facing, especially in the fields of Science, Technology, Engineering and Mathematics (STEM). Various approaches have been proposed to soften this issue. By now the most successful approach is to attract pre-university youth and university freshmen into those fields before they make a decision on future subjects by introducing them with interactive, modifiable and inspiring virtual environments, which incorporates most essential knowledge of STEM. We propose to design a comprehensive virtual reality platform with immersive interactions, pluggable components and flexible configurations. It also involves haptics, motion capture and gesture recognition, and could be deployed in both local and distributed environments. The platform utilizes off the shelf low cost haptics and motion capture products, however the fidelity can be maintained at a good level. The proposed platform has been implemented with different configurations and has been tested on a group of users. Preliminary test results show that the interactivity, flexibility and fidelity of the platform are highly appreciated by users. User surveys also indicate that the proposed platform could help pre-university students and university freshmen build an overview of various aspects of STEM education. Besides, users are also positive on the fact that the platform enabled them to identify the challenges for higher education in STEM by providing them opportunities to interactively modify system configurations and instantly experience the corresponding results both visually and haptically.