Point-cloud-based model-mediated teleoperation

Abstract

In this paper, we extend the concept of model-mediated teleoperation (MMT) for complex environments and six degrees of freedom interaction using point cloud surface models. In our system, a time-of-flight camera is used to capture a high resolution point cloud model of the object surface. The point cloud model and the physical properties of the object (stiffness and surface friction coefficient) are estimated at the slave side in real-time and transmitted to the master side using the modeling and updating algorithm proposed in this work. The proposed algorithm adaptively controls the updating of the point cloud model and the object properties according to the slave movements and by exploiting known limitations of human haptic perception. As a result, perceptually irrelevant transmissions are avoided, and thus the packet rate in the communication channel is substantially reduced. In addition, a simple point cloud-based haptic rendering algorithm is adopted to generate the force feedback signals directly from the point cloud model without first converting it into a 3D mesh. In the experimental evaluation, the system stability and transparency are verified in the presence of a round-trip communication delay of up to 1000ms. Furthermore, by exploiting the limits of human haptic perception the presented system allows for a significant haptic data reduction of about 90% for teleoperation systems with time delay. Index Termsmodel-mediated teleoperation, model-update, packet rate reduction, point cloud-based haptic rendering.

Adaptive Model-Mediated Teleoperation for Tasks Interacting With Uncertain Environment

“…The MMTs have been further developed to estimate the model parameters in real-time at the slave side so that the model accuracy can be preserved. Various models have been also applied, such as linear spring model [16], [23]- [25], linear spring-damper model [26], linear mass-spring-damper model [27]- [29], linear spring with Coulomb friction [30], [31]. Hunt-Crossley model, a widely used nonlinear viscoelastic model, is also employed with MMT [32].…”

Towards real-time modeling and haptic rendering of deformable objects for point cloud-based Model-Mediated Teleoperation

“…However, in most cases the environment is quite complex. Xu et al present a point cloud-based ModelMediated Teleoperation (pcbMMT) approach to deal with complex object geometry for static and rigid objects in [11]. As illustrated in Fig.…”