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The ultrasonic phased array as an emerging interactive tool is increasingly used for aerial tactile interaction. However, there is almost no method to achieve remote variable force feedback through the ultrasonic phased array as far as we know. This article presents a force tactile feedback method for teleoperating robot systems that tracks the fiv...
Citations
... The sensory threshold of the device was tested in order to provide significant tactile stimulation to the user and to maximize the number of stimuli that the wearable tactile display device could provide the user. A constant stimulus method was used to measure the difference threshold, also known as JND, which is the minimum change in the intensity of a stimulus that one can perceive [37]. It is a psychometric measure of the difference between two stimulus intensities. ...
A novel wearable upper arm tactile display device, which can simultaneously provide three types of tactile stimuli (i.e., squeezing, stretching, and vibration) is presented. The squeezing and stretching stimulation of the skin is generated by two motors simultaneously driving the nylon belt in the opposite and the same direction, respectively. In addition, four evenly spaced vibration motors are fixed around the user’s arm by an elastic nylon band. There is also a unique structural design for assembling the control module and actuator, powered by two lithium batteries, making it portable and wearable. Psychophysical experiments are conducted to investigate the effect of interference on the perception of squeezing and stretching stimulation by this device. Results show that (1) different tactile stimuli actually interfere with the user’s perception compared to the case where only one stimulus is applied to the user; (2) the squeezing has a considerable impact on the stretch just noticeable difference (JND) values when both stimuli are exerted on the user, and when the squeezing is strong, while the impact of stretch on the squeezing JND values is negligible.
... The team found that this new approach was consistent with conventional ultrasound. [11] Applying a force haptic feedback method, Liu, et al. [12] identified the haptic variable force feedback for remote ultrasonic robotics. ...
... 13) High-intensity focused airborne ultrasound gives tactile feedback through a real-time tracking system. 14) Ultrasound vibrations generated on a glass substrate can control the coefficient of friction between the skin and the substrate in touch panel devices, thereby providing a direct touch sensation to the user's fingertips. The acoustic radiation force generated by ultrasound vibration changes the contact state between the device and the skin, 15) resulting in a change in the electrical impedance of the touch panel that can be used to estimate the acoustic levitation and friction forces. ...
This paper investigates a thin sensor used to detect the position of an object in front of an ultrasonic transducer using changes in the radiation impedance. The sensor consists of a rectangular plate and a piezoelectric transducer, and the configuration is determined based on the results of a finite element analysis simulation. Stripe flexural vibration modes are generated on the plate, radiating sound waves into the air between the plate and the object. The radiation angle of these sound waves is dependent on the driving frequency, resulting in a change in the sound field and the electrical admittance characteristics. The sensing performance is examined using two resonant vibration modes. The sensor can determine the position of an object uniquely within a two-dimensional area, and the lower resonant mode gave a wider measurable range. The sensitivity is improved six-fold over that of our conventional sensor using the same sensing mechanism.
... Obviously, all of the studies above mainly have focused on the continuous-time teleoperation systems, neglecting the handling of some practical parameters such as dataswap, the sampling rate effect, and update rates of actuators on the system's stability. However, this investigation can be instructive in experimental studies such as [13], which proposes an open-source scheme of a wearable 7-DOF wireless operator arm motiontracking system for teleoperator systems or in [14], where a force tactile feedback approach for finger tracking systems is presented. ...
This study addresses sensor allocation by analyzing exponential stability for discrete-time teleoperation systems. Previous studies mostly concentrate on the continuous-time teleoperation systems and neglect the management of significant practical phenomena, such as data-swap, the effect of sampling rates of samplers, and refresh rates of actuators on the system’s stability. A multi-rate sampling approach is proposed in this study, given the isolation of the master and slave robots in teleoperation systems which may have different hardware restrictions. This architecture collects data through numerous sensors with various sampling rates, assuming that a continuous-time controller stabilizes a linear teleoperation system. The aim is to assign each position and velocity signals to sensors with different sampling rates and divide the state vector between sensors to guarantee the stability of the resulting multi-rate sampled-data teleoperation system. Sufficient Krasovskii-based conditions will be provided to preserve the exponential stability of the system. This problem will be transformed into a mixed-integer program with LMIs (linear matrix inequalities). These conditions are also used to design the observers for the multi-rate teleoperation systems whose estimation errors converge exponentially to the origin. The results are validated by numerical simulations which are useful in designing sensor networks for teleoperation systems.
... One of the mid-air tactile stimulation method is to evoke tactile sensation via virtual lumps modulated by a distant air-jet display (Gwilliam et al., 2013;Sodhi et al., 2013). Other types of mid-air haptic interfaces include tactile display based on focused ultrasound Yang et al., 2021). A sufficiently strong acoustic force induced by the focused ultrasound can evoke tactile sensation on the skin. ...
... Laser can be focused on a distant location with high precision from a remote source as long as ∼10 m. Such long-distance stimulation can overcome limitations of current ultrasonic or air jet mid-air stimulation technologies (Gwilliam et al., 2013;Jun et al., 2015;Kim et al., 2015;Ismo et al., 2020;Yang et al., 2021). Also, tactile stimulation using laser-induced plasma does not require an explicit elastic medium attached to the skin as in the previous study (Singh et al., 2014;Lee et al., 2016), making itself available to more general applications. ...
This study demonstrates the feasibility of a mid-air means of haptic stimulation at a long distance using the plasma effect induced by laser. We hypothesize that the stress wave generated by laser-induced plasma in the air can propagate through the air to reach the nearby human skin and evoke tactile sensation. To validate this hypothesis, we investigated somatosensory responses in the human brain to laser plasma stimuli by analyzing electroencephalography (EEG) in 14 participants. Three types of stimuli were provided to the index finger: a plasma stimulus induced from the laser, a mechanical stimulus transferred through Styrofoam stick, and a sham stimulus providing only the sound of the plasma and mechanical stimuli at the same time. The event-related desynchronization/synchronization (ERD/S) of sensorimotor rhythms (SMRs) in EEG was analyzed. Every participant verbally reported that they could feel a soft tap on the finger in response to the laser stimulus, but not to the sham stimulus. The spectrogram of EEG evoked by laser stimulation was similar to that evoked by mechanical stimulation; alpha ERD and beta ERS were present over the sensorimotor area in response to laser as well as mechanical stimuli. A decoding analysis revealed that classification error increased when discriminating ERD/S patterns between laser and mechanical stimuli, compared to the case of discriminating between laser and sham, or mechanical and sham stimuli. Our neurophysiological results confirm that tactile sensation can be evoked by the plasma effect induced by laser in the air, which may provide a mid-air haptic stimulation method.
Cutaneous haptic feedback has recently received great attention from researchers in the robotic teleoperation field, as it has been proven to convey rich information to the human operator while guaranteeing the safety and stability of the control loop. In fact, delivering ungrounded cutaneous cues keeps the teleoperation system stable even in the presence of time-varying destabilizing factors such as hard contacts or communication delays. This aspect is particularly relevant for all the applications and scenarios where the safety of the system is of paramount importance, as in medical robotics. This article presents an overview on cutaneous haptic interaction followed by a review of the literature on cutaneous/tactile feedback systems for robotic teleoperation, categorizing the considered systems according to the type of cutaneous stimuli they can provide to the human operator. The paper ends with a discussion on the role of cutaneous haptics in robotics and the perspectives of the field.
This paper investigates a method to detect the position of an object in front of an ultrasonic vibrator using changes in the radiation impedance. This acoustic touchless sensor is composed of a rectangular vibrating plate and two bolt-clamped Langevin-type transducers with stepped horns. The sensor configuration was determined based on the results of a finite element analysis simulation. When a stripe flexural vibration mode excited on the plate was generated an acoustic standing-wave field in the air, the electrical impedance of the ultrasound transducers changed dramatically, thus indicating that the radiation impedance of the sensor was dependent on the object position. By measuring the amplitude of the input current to the transducers and the phase difference between the input current and the voltage applied to the sensor, the 40-mm-long object’s position could be determined uniquely within a two-dimensional area of 160 mm×7 mm
This paper presents the design and development of a novel haptic sensor system. It integrates cable-driven force and ultrasonic tactile feedback, which can produce multimodal haptic stimuli. The sensing element includes a Leapmotion, an ultrasonic transducer array, tension sensors, and rotary encoders, which are used to capture hand posture, project tactile points, measure cable force and length, respectively. Firstly, a 6-DOF cable-driven force feedback apparatus based on parallel mechanism is designed and ultrasonic phased array is combined to form a multimodal haptic feedback system. Secondly, a multimodal haptic fusion method for cable-driven force and ultrasonic tactile is firstly proposed to invoke realistic compound haptic sensations. To enhance the rendering effects of each subsystem, admittance control is developed for a cable robot, and a new perceived magnitude model is established for ultrasound tactile rendering. A psychophysical experiment is conducted to study the perceived characteristics of multimodal haptic stimuli. To verify the proposed system, a series of experiments were carried out, whose results indicated that the system performs well at multi-property haptic rendering and confirm the accuracy and sensitive advantage of our system in virtual reality applications. The results of our study indicate that this device has great application potential in human-computer interaction.
