scholarly journals Design and Testing of Two Haptic Devices Based on Reconfigurable 2R Joints

2021 ◽  
Vol 12 (1) ◽  
pp. 339
Author(s):  
Mykhailo Riabtsev ◽  
Victor Petuya ◽  
Mónica Urízar ◽  
Oscar Altuzarra
Keyword(s):  
Force Feedback ◽  
Mechanical Design ◽  
Experimental Testing ◽  
Feedback System ◽  
Experimental Setup ◽  
Haptic Devices ◽  
Selection Principles ◽  
Detailed Interpretation ◽  
System Nodes ◽  
Design And Testing

This paper presents the design and testing of two haptic devices, based on reconfigurable 2R joints: an active 2R spherical mechanism-based joint and a differential gear-based joint. Based on our previous works, in which the design and kinematic analysis of both reconfigurable joints were developed, the experimental setup and the various tasks intended to test the reconfigurability, precision, force feedback system and general performance, are presented herein. Two control modes for the haptic device operation are proposed and studied. The statistical analysis tools and their selection principles are described. The mechanical design of two experimental setups and the main elements are considered in detail. The Robot Operating System nodes and the topics that are used in the software component of the experimental setup are presented and explained. The experimental testing was carried out with a number of participants and the corresponding results were analyzed with the selected statistical tools. A detailed interpretation and discussion on of the results is provided.

A Mechatronics Approach to Safe, Stable Teleoperation in Medical Applications

2000 ◽  
Author(s):  
David Wang ◽  
Gilbert Lai ◽  
Carmen Caradima
Keyword(s):  
Virtual Reality ◽  
Time Delay ◽  
Control Strategy ◽  
Force Feedback ◽  
Mechanical Design ◽  
Medical Applications ◽  
Force Sensors ◽  
Haptic Devices

Abstract Currently, remote interactions between patient and surgeon/doctor are limited to visual and audio aspects only. The general objective of the research presented in this paper is to explore force feedback teleoperation to improve the doctor/surgeon’s abilities. A control strategy is proposed which transmits forces, does not need expensive force sensors, and can be shown to be always stable. This technique should work for all “linear” haptic devices. The mechatronics approach has been taken in the mechanical design of the haptic devices to ensure linearity. The work presented in this paper will focus on the interactions between two haptic devices: the Virtual Reality Mouse 1 (VR Mouse), and a 5-bar linkage robot. Time delay issues involved in the teleoperation will also be discussed. The technique proposed in this paper will result in a very inexpensive workstation for teleoperation applications.

scholarly journals Development and Testing of a Methodology for the Assessment of Acceptability of LKA Systems

Machines ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 47 ◽  
Author(s):  
Luca Salvati ◽  
Matteo d’Amore ◽  
Anita Fiorentino ◽  
Arcangelo Pellegrino ◽  
Pasquale Sena ◽  
...  
Keyword(s):  
Force Feedback ◽  
Feedback System ◽  
Operating Conditions ◽  
Experimental Methodology ◽  
Driving Safety ◽  
Steering Wheel ◽  
Human In The Loop ◽  
Automation Systems ◽  
Driving Stability ◽  
Lane Keeping

In recent years, driving simulators have been widely used by automotive manufacturers and researchers in human-in-the-loop experiments, because they can reduce time and prototyping costs, and provide unlimited parametrization, more safety, and higher repeatability. Simulators play an important role in studies about driver behavior in operating conditions or with unstable vehicles. The aim of the research is to study the effects that the force feedback (f.f.b.), provided to steering wheel by a lane-keeping-assist (LKA) system, has on a driver’s response in simulators. The steering’s force feedback system is tested by reproducing the conditions of criticality of the LKA system in order to minimize the distance required to recover the driving stability as a function of set f.f.b. intensity and speed. The results, obtained in three specific criticality conditions, show that the behaviour of the LKA system, reproduced in the simulator, is not immediately understood by the driver and, sometimes, it is in opposition with the interventions performed by the driver to ensure driving safety. The results also compare the performance of the subjects, either overall and classified into subgroups, with reference to the perception of the LKA system, evaluated by means of a questionnaire. The proposed experimental methodology is to be regarded as a contribution for the integration of acceptance tests in the evaluation of automation systems.

Design of a Novel Parallel Mechanism for Haptic Device

2021 ◽  
pp. 1-63
Author(s):  
Jin Lixing ◽  
Duan Xingguang ◽  
Li Changsheng ◽  
Shi Qingxin ◽  
Wen Hao ◽  
...  
Keyword(s):  
Parallel Mechanism ◽  
Degrees Of Freedom ◽  
Force Feedback ◽  
Parallel Architecture ◽  
General Purpose ◽  
Haptic Device ◽  
Haptic Devices ◽  
Modeling And Optimization ◽  
Teleoperation Systems

Abstract This paper presents a novel parallel architecture with seven active degrees of freedom (DOFs) for general-purpose haptic devices. The prime features of the proposed mechanism are partial decoupling, large dexterous working area, and fixed actuators. The detailed processes of design, modeling, and optimization are introduced and the performance is simulated. After that, a mechanical prototype is fabricated and tested. Results of the simulations and experiments reveal that the proposed mechanism possesses excellent performances on motion flexibility and force feedback. This paper aims to provide a remarkable solution of the general-purpose haptic device for teleoperation systems with uncertain mission in complex applications.

Optimal mechanical design of modular haptic devices

2011 ◽  
Author(s):  
Pablo Cerrada ◽  
Jose Brenosa ◽  
Ignacio Galiana ◽  
Javier Lopez ◽  
Manuel Ferre ◽  
...  
Keyword(s):  
Mechanical Design ◽  
Haptic Devices

Evidence of positive force feedback among hindlimb extensors in the intact standing cat

1995 ◽  
Vol 73 (6) ◽  
pp. 2578-2583 ◽  
Author(s):  
C. A. Pratt
Keyword(s):  
Force Feedback ◽  
Functional Organization ◽  
Force Plate ◽  
Feedback System ◽  
Implanted Electrodes ◽  
Golgi Tendon Organs ◽  
Ia Afferents ◽  
Extensor Muscles ◽  
Stimulation Of ◽  
Positive Force

1. The functional organization of heterogenic reflexes produced by activation of extensor force receptors (Golgi tendon organs) was studied in intact cats during stationary stance. Intramuscular stimulation (200 Hz, 20 ms) of hindlimb extensor muscles via chronically implanted electrodes was used to evoke weak muscle contractions and naturally activate Golgi tendon organ Ib afferents while cats stood unrestrained with each paw on a moveable triaxial force plate. 2. Intramuscular stimulation of every hindlimb extensor muscle tested in this study evoked excitatory responses that were widely distributed among hindlimb extensor muscles. Source and target specializations in the functional organization of this positive force feedback system were also observed. For example, stimulation of ankle extensors typically excited extensors and flexors at the ankle and hip (but not knee), whereas stimulation of hip extensors typically excited only extensors at all three joints. In addition, intramuscular stimulation of either lateral (LG) or medial (MG) gastrocnemius consistently inhibited soleus while exciting other extensors at the ankle and more proximal joints. 3. The electromyographic (EMG) reflex responses described above are attributed to the natural (via muscle contraction) activation of extensor group Ib afferents. Direct activation of intramuscular afferents by the stimulus was unlikely because there was no evidence that Ia afferents, which have the lowest electrical thresholds, were activated. Both the observed inhibition of the synergist, soleus, and the excitation of the antagonist, tibialis anterior, produced by gastrocnemius stimulation are opposite to the reflex effects that would be produced at the ankle by activation of gastrocnemius Ia afferents.(ABSTRACT TRUNCATED AT 250 WORDS)

Mechanical Design and Testing of a 2.5 MW sCO2 Compressor Loop

2021 ◽  
Author(s):  
Stefan D. Cich ◽  
J. Jeffrey Moore ◽  
Chris Kulhanek ◽  
Meera Day Towler ◽  
Jason Mortzheim
Keyword(s):  
High Efficiency ◽  
Mechanical Design ◽  
Guide Vane ◽  
Operating Conditions ◽  
Inlet Guide Vane ◽  
Inlet Temperature ◽  
Design Changes ◽  
Wide Range ◽  
Inlet Conditions ◽  
Design And Testing

Abstract An enabling technology for a successful deployment of the sCO2 close-loop recompression Brayton cycle is the development of a compressor that can maintain high efficiency for a wide range of inlet conditions due to large variation in properties of CO2 operating near its dome. One solution is to develop an internal actuated variable Inlet Guide Vane (IGV) system that can maintain high efficiency in the main and re-compressor with varying inlet temperature. A compressor for this system has recently been manufactured and tested at various operating conditions to determine its compression efficiency. This compressor was developed with funding from the US DOE Apollo program and industry partners. This paper will focus on the design and testing of the main compressor operating near the CO2 dome. It will look at design challenges that went into some of the decisions for rotor and case construction and how that can affect the mechanical and aerodynamic performance of the compressor. This paper will also go into results from testing at the various operating conditions and how the change in density of CO2 affected rotordynamics and overall performance of the machine. Results will be compared to expected performance and how design changes were implanted to properly counter challenges during testing.

scholarly journals Method for the Detection of Tumor Blood Vessels in Neurosurgery Using a Gripping Force Feedback System

Sensors ◽  
2019 ◽  
Vol 19 (23) ◽  
pp. 5157
Author(s):  
Hiroki Yokota ◽  
Takeshi Yoneyama ◽  
Tetsuyou Watanabe ◽  
Yasuo Sasagawa ◽  
Mitsutoshi Nakada
Keyword(s):  
Blood Vessel ◽  
Blood Vessels ◽  
Force Feedback ◽  
Correlation Coefficients ◽  
Feedback System ◽  
Force Sensor ◽  
Robot System ◽  
Blood Vessel Detection ◽  
Operating Space ◽  
Gripping Force

Avoiding unnecessary bleeding during neuroendoscopic surgeries is crucial because achieving hemostasis in a narrow operating space is challenging. However, when the location of a blood vessel in a tumor cannot be visually confirmed, unintentional damage to the vessel and subsequent bleeding may occur. This study proposes a method for tumor blood vessel detection using a master–slave surgical robot system equipped with a force sensor in the slave gripper. Using this method, blood pulsation inside a tumor was detected, displayed as a gripping force wave, via the slave force sensor. The characteristics of gripping force due to blood pulsation were extracted by measuring the fluctuation of the force in real time. The presence or absence of blood vessels was determined on the basis of cross-correlation coefficients between the gripping force fluctuation waveform due to blood pulsation and model fluctuation waveform. Experimental validation using two types of simulated tumors (soft: E = 6 kPa; hard: E = 38 kPa) and a simulated blood vessel (E = 1.9 MPa, radius = 0.5 mm, thickness = 0.1 mm) revealed that the presence of blood vessels could be detected while gripping at a constant angle and during transient gripping.

scholarly journals Preliminary Results in Testing of a Novel Asymmetric Underactuated Robotic Hand Exoskeleton for Motor Impairment Rehabilitation

Symmetry ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1470 ◽  
Author(s):  
Flaviu Ionuț Birouaș ◽  
Radu Cătălin Țarcă ◽  
Simona Dzitac ◽  
Ioan Dzitac
Keyword(s):  
Mechanical Design ◽  
Experimental Testing ◽  
Motor Impairment ◽  
Human Hand ◽  
Underactuated System ◽  
Robotic Hand ◽  
Advantages And Disadvantages ◽  
Hand Exoskeleton ◽  
Robotic Devices ◽  
And Behavior

Robotic exoskeletons are a trending topic in both robotics and rehabilitation therapy. The research presented in this paper is a summary of robotic exoskeleton development and testing for a human hand, having application in motor rehabilitation treatment. The mechanical design of the robotic hand exoskeleton implements a novel asymmetric underactuated system and takes into consideration a number of advantages and disadvantages that arose in the literature in previous mechanical design, regarding hand exoskeleton design and also aspects related to the symmetric and asymmetric geometry and behavior of the biological hand. The technology used for the manufacturing and prototyping of the mechanical design is 3D printing. A comprehensive study of the exoskeleton has been done with and without the wearer’s hand in the exoskeleton, where multiple feedback sources are used to determine symmetric and asymmetric behaviors related to torque, position, trajectory, and laws of motion. Observations collected during the experimental testing proved to be valuable information in the field of augmenting the human body with robotic devices.

Sign in / Sign up

Export Citation Format

Share Document