Influence of Vibration Modes and Human Operator on the Stability of Haptic Rendering

In this article, the system for monitoring of the emotional state changes of the air navigation system's human operator in the extreme situations, based on the using of the prior models of the operator activity which built on the posterior researches of actual material of the aviation accidents investigations, has been proposed. The stability of aviation man-machine system “human-operator – aircraft” during the deformations of the operator's emotional experience has been defined according to the Nyquist criterion. A computer program for diagnostics of the emotional state of the human operator has been developed. The system based on monitoring of the current emotional state of the air navigation system's human operator and diagnostics of the deformations of emotional experience with the determination of the operator's functional stability will allow preventing the development of potentially hazardous flight situations towards worsening in a proactive manner.

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Delayed-Acceleration Feedback for Active-Multimode Vibration Control of Cantilever Beams

Volume 5: 6th International Conference on Multibody Systems, Nonlinear Dynamics, and Control, Parts A, B, and C ◽

10.1115/detc2007-34793 ◽

2007 ◽

Author(s):

Khaled A. Alhazza ◽

Ali H. Nayfeh ◽

Mohammed F. Daqaq

Keyword(s):

Cantilever Beam ◽

Controller Design ◽

Equations Of Motion ◽

Time Integration ◽

Free Vibrations ◽

Delayed Feedback Control ◽

Vibration Modes ◽

Stability Boundaries ◽

Single Input Single Output ◽

The Stability

We present a single-input single-output multimode delayed-feedback control methodology to mitigate the free vibrations of a flexible cantilever beam. For the purpose of controller design and stability analysis, we consider a reduced-order model consisting of the first n vibration modes. The temporal variation of these modes is represented by a set of nonlinearly-coupled ordinary-differential equations that capture the evolving dynamics of the beam. Considering a linearized version of these equations, we derive a set of analytical conditions that are solved numerically to assess the stability of the closed-loop system. To verify these conditions, we characterize the stability boundaries using the first two vibration modes and compare them to damping contours obtained by long-time integration of the full nonlinear equations of motion. Simulations show excellent agreement between both approaches. We analyze the effect of the size and location of the piezoelectric patch and the location of the sensor on the stability of the response. We show that the stability boundaries are highly dependent on these parameters. Finally, we implement the controller on a cantilever beam for different controller gain-delay combinations and assess the performance using time histories of the beam response. Numerical simulations clearly demonstrate the controller ability to mitigate vibrations emanating from multiple modes simultaneously.

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Analysis of the Chatter Instability in a Nonlinear Model for Drilling

Journal of Computational and Nonlinear Dynamics ◽

10.1115/1.2338648 ◽

2006 ◽

Vol 1 (4) ◽

pp. 294-306 ◽

Cited By ~ 7

Author(s):

Sue Ann Campbell ◽

Emily Stone

Keyword(s):

Stability Analysis ◽

Hopf Bifurcation ◽

Nonlinear Models ◽

Stability Boundary ◽

Vibration Modes ◽

Loss Of Stability ◽

Chatter Vibration ◽

Cutting Depth ◽

Stability And Bifurcation Analysis ◽

The Stability

In this paper we present stability analysis of a non-linear model for chatter vibration in a drilling operation. The results build our previous work [Stone, E., and Askari, A., 2002, “Nonlinear Models of Chatter in Drilling Processes,” Dyn. Syst., 17(1), pp. 65–85 and Stone, E., and Campbell, S. A., 2004, “Stability and Bifurcation Analysis of a Nonlinear DDE Model for Drilling,” J. Nonlinear Sci., 14(1), pp. 27–57], where the model was developed and the nonlinear stability of the vibration modes as cutting width is varied was presented. Here we analyze the effect of varying cutting depth. We show that qualitatively different stability lobes are produced in this case. We analyze the criticality of the Hopf bifurcation associated with loss of stability and show that changes in criticality can occur along the stability boundary, resulting in extra periodic solutions.

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Haptic force rendering of rigid-body interactions: A systematic review

Advances in Mechanical Engineering ◽

10.1177/16878140211041538 ◽

2021 ◽

Vol 13 (9) ◽

pp. 168781402110415

Author(s):

Yang Wang ◽

Lei Feng ◽

Kjell Andersson

Keyword(s):

Systematic Review ◽

Rigid Body ◽

Haptic Rendering ◽

Body Interaction ◽

The Stability ◽

Technical Terms

Haptic rendering has been developing for decades with different rendering approaches and many factors that affect the stability when rendering rigid-body interactions have been investigated. To get an overall understanding of the challenges in haptic rendering, we approach this topic by conducting a systematic review. This review examines different haptic rendering approaches and how to deal with instability factors in rendering. A total of 25 papers are reviewed to answer the following questions: (1) what are the most common haptic rendering approaches for rigid-body interaction? and (2) what are the most important factors for instability of haptic rendering and how to address them? Through the process of investigating these questions, we get the insight that transparency can be further explored and technical terms to describe haptic rendering can be more standardized to push the topic forward.

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A Screw-Axis Approach to the Stability of Two-Wheeled Vehicles

Applied Sciences ◽

10.3390/app11167393 ◽

2021 ◽

Vol 11 (16) ◽

pp. 7393

Author(s):

Matteo Bova ◽

Matteo Massaro

Keyword(s):

Laboratory Tests ◽

Three Dimensional ◽

Mode Shapes ◽

Vibration Modes ◽

Side View ◽

Centre Of Mass ◽

Vehicle Model ◽

Screw Axis ◽

The Stability ◽

Wheeled Vehicles

The stability of two-wheeled vehicles is predominantly characterized by the well-known weave and wobble vibration modes, which have been extensively investigated in the literature, mainly in terms of their frequencies and damping ratios. In this work the focus is towards their mode shapes, which are investigated using the screw-axis (also called Mozzi-axis), instead of the classic compass diagrams, for a better understanding of their three-dimensional patterns. The analysis is then carried out using the velocity centres for a characterization from the top, rear and side view of the vehicle. The multibody vehicle model employed for the numerical analysis is built in Adams. The dataset resembles that of a 250cc sport motorcycle, and has been derived from laboratory tests. The stability analysis is carried out in the frequency domain. It is found that, depending on the selected plane for the projection of the three-dimensional vibration motion, the trajectories of the velocity centres of the weave and wobble can cross either aft or fore the centre of mass, which has been associated to the under- and over-steering behaviour in the literature.

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Stability Analysis and Improvement of Virtual Wall Model

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.464.183 ◽

2011 ◽

Vol 464 ◽

pp. 183-186

Author(s):

Jia Lu Li ◽

Ai Guo Song ◽

Xiao Rui Zhang

Keyword(s):

Haptic Rendering ◽

System Stability ◽

Unstable State ◽

Prototype System ◽

Sampled Data ◽

Wall Model ◽

Passive Behavior ◽

Energy Conversation ◽

The Stability ◽

Main Factor

Sampled-data system’s nature is the main factor that causes virtual wall to demonstrate active (non-passive) behavior, destroying the illusion of reality. To enhance the stability of haptic rendering by virtual wall model, a novel spring-impulse model based on energy conversation and momentum conversation is proposed. In the model, an impulse in the opposite direction of avatar’s velocity is exerted on avatar at the instant from inner of virtual wall back to balance position during unstable state. This resistant forces eliminate extra work to reduce the non-passive behaviors of the haptic system, which lead to improved realistic rigid perceptions and system stability. The experiments have verified the effectiveness of our spring-impulse method in a virtual stiff-wall prototype system via a Phantom Omni haptic device.

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Toward Stable and Realistic Haptic Interaction for Tooth Preparation Simulation

Journal of Computing and Information Science in Engineering ◽

10.1115/1.3402759 ◽

2010 ◽

Vol 10 (2) ◽

Cited By ~ 7

Author(s):

Jun Wu ◽

Dangxiao Wang ◽

Charlie C. L. Wang ◽

Yuru Zhang

Keyword(s):

Haptic Rendering ◽

Force Model ◽

Haptic Interaction ◽

Dental Surgery ◽

Virtual Coupling ◽

Update Rate ◽

Surgery First ◽

Tooth Preparation ◽

The Stability ◽

Haptic Sensation

In this paper, we present the methods to generate a stable and realistic simulator for dental surgery. First, a simplified force model is derived from grinding theory by considering the complex bur shape and dental handpiece’s dynamic behavior. While the force model can be evaluated very fast to fulfill the high update rate of haptic rendering, it also explains basic haptic sensation features in tooth preparation operation. Second, as direct rendering of this damping-like force model may induce instability of the haptic device, we apply a virtual coupling based method to guarantee the stability in haptic rendering. Furthermore, implicit integration of the bur’s motion equation is utilized to ensure numerical stability. Third, to overcome force discontinuity caused by locally removing tooth materials, we define a two-layer based representation for the bur, where the boundary voxels are adopted to compute forces and the interior voxels are employed to remove materials from teeth. The experimental results agree with the real sensation described by experienced dentists.

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