Absence Of Vibration Research Articles

Investigation of Ti0.92+xZr0.1−xCr1.0Mn0.6Fe0.4 Alloys for Use as 25 MPa Hydrogen Compression Materials

Metal hydride hydrogen compressors have attracted great attention due to their reliable safety, environmental friendliness, and the absence of vibration and noise. Herein, the effects of Ti substitution for Zr on the crystal structure and hydrogen compressive performance of Ti0.92+xZr0.1−xCr1.0Mn0.6Fe0.4 (x = 0, 0.01, 0.02, and 0.03) are investigated systematically. Among the investigated alloys, the Ti0.94Zr0.08Cr1.0Mn0.6Fe0.4 alloy can be considered as a promising candidate for application with a hydrogen capacity of 1.67 wt.% under 8 MPa at 10 °C. Additionally, it exhibits excellent cyclic stability. The desorption pressure at 83.9 °C was determined to be 25 MPa by van’t Hoff fitting plots, which fulfills the requirement of producing over 25 MPa hydrogen pressure in water-bath environments with a high compression ratio of 3.08. The Ti0.94Zr0.08Cr1.0Mn0.6Fe0.4 alloy is very promising for hydrogen refueling applications in long-tube trailers and low-pressure gas cylinders.

Nafion/graphite-bismuth nanoplate with a vibration unit for portable heavy metal ion detection

Contamination of natural resources, particularly water sources, by heavy metal ions, even at low concentrations, poses a significant threat to ecosystems and human health, underscoring the importance of developing sensors with point-of-use (POU) applications. To that end, a vibration-unit-equipped portable electrochemical system (vPES) capable of extremely sensitive detection of Pb2+ and Cd2+ in water is reported herein. The vibration unit enhances sensitivity by facilitating sample diffusion, and its compactness makes it suitable for point-of-use applications through mobile phone connectivity. The system also integrates Nafion and a graphite/bismuth-nanoplate-functionalized screen-printed carbon electrode to detect heavy metals efficiently. The approach implemented in this study and validated through experiments and simulations suggests that vibration-based mixing leads to 540 % and 511 % higher Pb2+ and Cd2+ detection efficiencies, respectively, than those in the absence of vibration. Additionally, the sensor exhibits the limits of detection of 0.98 and 1.65 nM for Pb2+ and Cd2+, respectively, in laboratory environments. Samples collected from the Nakdong River in Korea and real environmental specimens—freshwater, soil, and serum—validate the detection performance. Overall, this study highlights the potential of vPES as a rapid, sensitive POU sensor for heavy metal detection, thereby bolstering environmental and public health monitoring efforts.

Effect of steel fiber shape and content on printability, microstructure and mechanical properties of 3D printable high strength cementitious materials

This study investigates the effects of steel fiber shape (straight and hooked-end) and content (0, 0.5, 1.0, and 1.5 vol%) on rheological properties, printability, mechanical performance and microstructure of 3D printable steel fiber reinforced high strength concrete (3DP-SFHSC). The results indicate that the increase of fiber content improves the mechanical behaviors of 3DP-SFHSC, but the extrudability suffers from reduction when the fiber content exceeded 1.0 vol% due to the significant increase in yield stress. The addition of 1.5 vol% hooked-end fibers enhances the compressive strength of 3DP-SFHSC by 8%, 25.7%, and 40.4% in the X, Y, and Z directions, respectively. Additionally, it also improves the tensile strength in the X direction by 37.67%. The printed specimens exhibit weaker mechanical properties compared to the cast specimens. On the one hand, the lower fiber-matrix compactness resulting from the absence of vibration during printing leads to increased porosity and weak bonding between the steel fibers and matrix. On the other hand, the inconsistent movement between fibers and mortar matrix during extrusion process may also cause the formation of gaps around fibers. Straight fibers show pronounced enhancements in buildability, compressive strength and tensile strength compared to hooked-end fibers at the same fiber volume fraction. Straight fibers align easily during the extrusion process, contributing to a matrix with lower porosity and smaller average pore size.

Effect of vibrational modes on fluidization characteristics and solid distribution of cohesive micro- and nano-silica powders

In this study, the impact of different vibrational modes on the fluidization characteristics of cohesive micro- and nano-silica powder was examined. Fractional pressure drop, bed expansion measurements, and X-ray imaging were utilized to characterize the fluidization quality. The densities of the emulsion phase at the top and bottom of the column were quantified and compared, providing insights into the solid distribution within the fluidized bed. In the absence of vibration, neither powder could be fluidized within the considered range of superficial gas velocities. Vertical vibration was found to initiate fluidization for both powders. In contrast, elliptical vibration failed to overcome the channelling behavior when fluidizing the micro-powder. For nano-powder, combined channelling and powder compaction occurred when the bed was subjected to elliptical vibration. For the micro-powder, it was observed that bed homogeneity was independent of vertical vibration intensity but improved with increasing superficial gas velocity. For nano-powder, intensifying vertical vibration led to segregation, likely due to agglomerate densification. Furthermore, fractional pressure drop measurements proved to be a strong tool in assessing fluidization quality, providing insights that could not be attained by conventional indicators.

Vibration and Slope Conditions during Harvesting Affect Radish Mass Measurements for Yield Monitoring: An Experimental Study Using a Laboratory Test Bench.

Site-specific measurements of the crop yield during harvesting are essential for successfully implementing precision management techniques. This study aimed to estimate the mass of radish tubers using the impact principle under simulated vibration and sloped-field harvesting conditions with a laboratory test bench. These conditions included the conveyor speed (CS), impact plate layout (IP), falling height onto the impact plate (FH), the plate angle relative to the horizontal (PH), the field slope, and the vibration of the harvesting machine. Two layouts of impact-type sensors were fabricated and tested, one with a single load cell (SL) and the other with two load cells (DL). An adjustable slope platform and a vibration table equipped with vibration blades were utilized to simulate the slope and vibration effects, respectively. Calibrations were conducted to verify the accuracy of the sensor outputs, processed with the finite impulse response and moving average filters. Radish mass was estimated using an asymmetrically trimmed mean method. The relative percentage error (RE), standard error (SE), coefficient of determination (R²), and analysis of variance (ANOVA) were used to assess the impact plate performance. The results indicated that the SE for both impact plates was less than 4 g in the absence of vibration and slope conditions. The R2 for the single and double impact plates ranged from 0.58 to 0.89 and 0.69 to 0.81, respectively. The FH had no significant impact, while the PH significantly affected the mass measurements for both impact plates. On the other hand, the CS significantly affected the plate performance, except for the double-load-cell impact plate. Both vibration and slope affected the mass measurements, with RE values of 9.89% and 13.92%, respectively. The RE for filtered radish signals was reduced from 9.13% to 5.42%. The tests demonstrated the feasibility of utilizing the impact principle to assess the mass of radishes, opening up possibilities for the development of yield-monitoring systems for crops harvested in a similar manner.

The Shape of a Compressible Drop on a Vibrating Solid Plate

The influence of high-frequency vibrations on the shape of a compressible drop placed on an oscillating solid substrate is studied in this paper. Due to the significant difference in characteristic temporal scales, the average and pulsating motions of the drop can be considered separately. For nearly hemispherical drop, the solution to the problem of pulsating motion is found in the form of series in Legendre polynomials. Frequencies of natural sound oscillations of hemispherical axisymmetric drop are obtained. Resonances of the acoustic mode of drop oscillations are found. The problem of forced oscillations of hemispherical drop in the limit of weakly compressible liquid is considered. It is found that drop oscillation amplitude grows with vibration intensity according to quadratic law, which is consistent with the solution of the pulsation problem for finite compressibility assumption. A variational principle for calculation of average drop shape is formulated based on minimization of energy functional for the case, so the compressibility of the liquid should be taken into account. It is shown that the functional (the sum of the kinetic and potential energies of the pulsating flow, the kinetic energy of the averaged flow, and the surface tension energy of the drop) decreases and reaches a minimum value at quasi-equilibrium state, in which the average shape of the drop becomes static. The influence of vibrations on the drop shape is studied for small values of the vibrational parameter. The surface of the drop in the absence of vibrations is assumed to be hemispherical. Calculations showed that under vibrations, drop height decreases, while the area of the base increases.

Fabrication of a citrus flavonoid hesperetin-capped gold nanoparticles-reduced graphene oxide nanocomposites (Hes-Au/rGONCs) as a potential therapeutic agent for triple negative breast cancer and bacterial infections

Hesperetin (Hes) is a Citrus Flavonoid, which is confirmed to have extensive therapeutic effects, comprising antimicrobial, antioxidant, anticancer, cardiovascular protection, and so forth. To overcome the poor solubility, here we attempt to synthesize the Hes-mediated gold nanoparticles bio-functionalized in reduced Graphene oxide (Hes-Au/rGONCs) to increase the therapeutic efficacy of Hes. The characterization of synthesized Hes-Au/rGONCs were analysed using UV–vis spectrophotometry, FT-IR, Raman spectroscopy, X-ray diffraction analysis (XRD), XPS, HPLC, SEM, EDX and HR-TEM. The absence of vibrations at 1516 and 1381 cm−1 shows the involvement of hydroxyl groups of phenols and enols in anchoring Au on the surface of rGO. In XRD, the planes at (111), (200), (220) and (311) revealed the face centered cubic (fcc) crystalline structure of gold nanoparticles that were functionalized on rGO nanosheets. Hes-Au/rGONCs synthesised produced a highly negative zeta potential of -36.44 mV due to their stability. The Hes-rGO/Au-NPs were analysed for their surface morphology by SEM. The HR-TEM micrographs exhibited uniform distribution and homogenous spherical shaped AuNPs with an average size of 21.37±5.7 nm on rGO sheets. The bio reduction percentage was calculated as 98.86% by using HPLC. The inhibitory concentration (IC50) of free-Hes and nanocomposites were 157.57 and 38.41 µM, respectively. The Hes-Au/rGONCs possess effective bactericidal activity against gram positive bacterial species than against gram negative bacterial strains. The resazurin dye assay confirms the MIC values of Hes-Au/rGONCs. Hereby, the outcome of these studies suggested that the fabricated Hes-Au/rGONCs have potential biomedical applications.

Corticospinal modulation of vibration-induced H-reflex depression.

The purpose of this study was to examine corticospinal modulation of spinal reflex excitability, by determining the effect of transcranial magnetic stimulation (TMS) on soleus H-reflexes while they were almost completely suppressed by lower extremity vibration. In 15 healthy adults, a novel method of single-limb vibration (0.6g, 30Hz, 0.33mm displacement) was applied to the non-dominant leg. Soleus muscle responses were examined in six stimulation conditions: (1) H-reflex elicited by tibial nerve stimulation, (2) tibial nerve stimulation during vibration, (3) subthreshold TMS, (4) subthreshold TMS during vibration, (5) tibial nerve stimulation 10ms after a subthreshold TMS pulse, and (6) tibial nerve stimulation 10ms after a subthreshold TMS pulse, during vibration. With or without vibration, subthreshold TMS produced no motor evoked potentials and had no effect on soleus electromyography (p > 0.05). In the absence of vibration, H-reflex amplitudes were not affected by subthreshold TMS conditioning (median (md) 35, interquartile range (IQ) 18-56 vs. md 46, IQ 22-59% of the maximal M wave (Mmax), p > 0.05). During vibration, however, unconditioned H-reflexes were nearly abolished, and a TMS conditioning pulse increased the H-reflex more than fourfold (md 0.3, IQ 0.1-0.7 vs. md 2, IQ 0.9-5.0% of Mmax, p < 0.008). Limb vibration alone had no significant effect on corticospinal excitability. In the absence of vibration, a subthreshold TMS pulse did not influence the soleus H-reflex. During limb vibration, however, while the H-reflex was almost completely suppressed, a subthreshold TMS pulse partially restored the H-reflex. This disinhibition of the H-reflex by a corticospinal signal may represent a mechanism involved in the control of voluntary movement. Corticospinal signals that carry the descending motor command may also reduce presynaptic inhibition, temporarily increasing the impact of sensory inputs on motoneuron activation.

Using good vibrations: Melting and controlled shear jamming of dense granular suspensions

Flows of suspensions can be blocked when the suspended particles are densely packed. This makes their formulation and their transport challenging in the industry. In this paper, we study the impact of vibrations on the behavior of dense granular suspensions prepared at a volume fraction above their jamming volume fraction but below the particle assembly random close packing. Vibrations are shown to have a strong effect on their rheological properties and to tune their transition from solidlike to liquidlike behavior. We study suspensions of rough silica particles in a Newtonian fluid. In the absence of vibrations, they have a solidlike behavior: they flow only above a yield stress. Particles are confined by the liquid interface, and the yield stress is of the frictional origin. When vibrations are applied, the yield stress vanishes to give rise to a liquidlike pseudo-Newtonian behavior at a low shear rate. Using shear-reversal experiments, we show that these liquidlike vibrated suspensions of frictional particles behave like nonvibrated suspensions of frictionless particles. As the shear rate is increased, we observe a shear thickening of the vibrated suspensions, eventually leading to shear-jamming. The yield stress behavior is recovered, and vibrations have no more impact. We show that this shear thickening can be tuned by changing the vibration energy injected into the system. We, finally, propose a physical picture based on the competition between contact opening by vibration and contact formation by shear to account for these behaviors. In the framework of the Wyart and Cates [Phys. Rev. Lett. 112, 098302 (2014)] model, vibrations can be seen as introducing a thermal-like repulsive force, yielding a critical stress proportional to the vibration stress introduced by Hanotin et al. [J. Rheol. 59, 253–273 (2015)].

A new quick-stop device to study the chip formation mechanism in metal cutting: Computational and experimental investigation

Understanding the chip formation mechanisms during machining is an important factor to facilitate the choice of cutting tools and machining parameters. Despite the appearance of new sophisticated methods and advanced equipment, the technique so called quick-Stop Test (QST) remains efficient, less costly, and easier to apply in the investigation of chip formation in cutting process. In present paper a new Quick-Stop Device QSD is designed, numerically simulated, implemented, and tested. The reformed QST technique uses a QSD device which operates on the modified Charpy pendulum. Accordingly, design of new QSD is presented and deeply described, and 2D FE modeling of the new QST, including the application of the appropriate boundary conditions, has been carried out. Moreover, chip formation and morphology for different cutting conditions have been effectively simulated. Subsequently, quick stop cutting operations including metal cutting tests of high alloyed tool steel (AISI D2) using fabricated new QSD are performed. Preliminary results of quick-stop experiment from current investigation prove the effectiveness of the new designed QSD in matter of rigidity, safety, and absence of vibration, while providing a fast set up time and allowing extremely short workpiece-cutting tool separation time and guarantee the generation of chip with its root. The photomicrographs of chip root samples gathered from hard metal cutting experiments including various cutting speeds machining conditions, enables clear observation of segmented chip formation mechanisms, thereby, highly promising the new designed QSD for the purpose of investigation of the different cutting parameters influencing the chip formation and morphology.

Preliminary analyses of an innovative soil improving system by sand/gravel injections–Geotechnical and geophysical characterization of a first test site

Several soil improving systems are available to increase the geotechnical properties of low resistance soils and increase the stability of overlaying constructions. Most of the already available methods make use of injections of more compacted material inside the ground, like: micro-piles, sand compaction piles, stone columns or grouting. Most of these solutions requires vibrations and rotary drilling, which could compromise soil properties and overlaying building integrity. Recently an innovative soil improving system by injections of a sand/gravel mixture was developed by Novatek® through mechanical preload of the mixture by compression adopting a hydraulic jack. The advantage of this last system with respect to available methods is the absence of vibrations and rotary drilling operations. In this study, the application of this system is documented in a first trial test site in the central Po plain (Italy). Description of the system and of the executed injections are reported. Characteristics of the ground before and after injections are compared, using both geotechnical and geophysical tests, in order to evaluate the system performances, which were also ascertained with direct verification through an explorative trench. The first results reported, even if for limited application depths, highlight the good potentialities of the improving system with respect to the increase of geotechnical parameters in the treated soil.

Piezoelectric Bone Surgery. Overview in Applications and Proof of Feasibility in Hand and Plastic Surgery.

Piezoelectric bone surgery was already extensively used in a number of surgical procedures ranging from dental to maxillofacial surgery. The authors aimed to determine whether piezosurgery was suitable and advantageous for performing osteotomies in Hand and Plastic reconstructive surgery. The authors overviewed a variety of applications for Piezosurgery® Device, from Mectron, in bone reconstructive surgery with over the last 8years. An overall number of 156 bone cutting procedures in adults and children was described at the phalanges, metacarpal bones and distal radius level, as well as in bone graft harvesting and bone remodeling following carpal scaphoid nonunion, scapho-lunate bone-ligament-bone reconstruction and fibula free flap in maxillofacial defects. The consolidation rate was 87.5% in scaphoid nonunion grafting and fixation. Bone healing was achieved in all other cases. No intra-operative complications were recorded. Piezosurgery® allowed high precision in bone cutting as well as custom-made graft and surface roughness were obtained, while preserving nerves, vessels and tendons integrity. The instrument may be handling moved into the surgical space in absence of vibrations, with a clear view onto the bone. The mechanical and biological characteristics of the piezoelectrical effect perfected this technique as an effective and useful instrument in Hand and Plastic surgery. The selective bone cutting properties avoided injuries to the surrounding soft tissues and thermal damage of the bony cells. Best advantages were described in feasibility and flexibility for intra-articular osteotomies, custom-made grafts and reconstructive microsurgical techniques.

Influence of blade vibration on part-span rotating stall

This paper presents the interaction between blade vibration and part-span rotating stall in a multi-stage high speed compressor. Unsteady aerodynamic and aeroelastic simulations were conducted using URANS CFD. Steady state computations showed short length scale disturbances formed local to the tip of a front stage rotor. Using a full annulus model, these disturbances were shown to coalesce into flow structures rotating around the annulus at approximately 76% of the shaft rotational speed. Natural evolution of the rotating stall did not result in a coherent spatial pattern. Sensitivity studies showed that operating point and tip clearance have significant impact on the developed state of rotating stall. Subsequent analyses carried out with prescribed rotor blade vibration showed a spatial ‘lock-in’ event where the circumferential order of the part-span rotating stall shifted to match that induced by the vibration mode. Moreover, in contrast to its natural form in the absence of vibration, the fully developed rotating stall showed a coherent stall signal. More importantly, it was found that numerical boundary conditions such as mixing plane and sliding planes can significantly influence the outcome of prediction.

Effect of Vibration on Surface Roughness in Finish Turning: Simulation Study

This paper presents the results of simulation analyses carried out to investigate the effect of adding controlled vibration of varying amplitudes and frequencies onto simulated workpiece profiles on surface roughness. The surface profiles were generated using the nose edge image of a real cutting tool insert at various stages of wear. The invariant moment sub-pixel edge detection method was used to extract the precise tool nose profile. The extracted nose profile was duplicated 20 times to generate the simulated workpiece profile. Vibration signals in the form of sine waves of amplitudes 0 to 50 % of the peak-to-valley height of the original workpiece profile and various frequencies were added to the simulated profile. Noise signals emanating from real machining were also added to the original profile to investigate their effect on roughness. The simulation study has shown that average roughness may increase continuously or fluctuate randomly depending on the magnitude of vibration added to the vibration-free workpiece profile. In the absence of vibration, the surface roughness of the workpiece decreases due to flattening effect of the tool nose during early stages of tool wear.

Analysis of a novel concept of 2-stroke rod-less opposed pistons engine (2S-ROPE): Testing, modelling, and forward potential

As pollutants and fuel consumption requirements become more constraining, new internal combustion engines generation arise to fulfill future automobile market regulations. In these context spark ignition (SI) engines working under hybridized structures are expected to represent one of the most viable and feasible technical approaches. In parallel to the already implemented 4-stroke turbocharged engines, new engine concepts are being conceived from their birth to meet nowadays standards. This work shows a new engine concept assessed to fit series hybrid configurations from the earliest design stages, and to fulfil requirements of the named “zero-emissions” urban areas. In this research work, a new opposed piston 2-stroke engine architecture based on rod-less innovative kinematics is described. The potential of this engine is based on its compactness, absence of vibrations and simplicity, going in hand with very competitive figures in terms of power density and fuel consumption. The engine unit has been designed, assembled, and tested to analyze several performance aspects, such as gas exchange and combustion. Taking advantage of the experimental campaign, a one-dimensional (1D) gas-dynamics engine model was developed and validated. Finally, the engine model was used for analyzing several potential upgrades and results have been discussed in detail. The target has always been to improve fuel consumption figures, below the best standards in market available internal combustion engines, while keeping engine concept simplicity and building costs.

Dynamics of the Tippe Top on a Vibrating Base

This paper studies the conditions under which the tippe top inverts in the presence of vibrations of the base along the vertical. A vibrational potential is constructed by averaging and it is shown that, when this potential is added to the system, the Jellett integral is preserved. This makes it possible to apply the modified Routh method and to find the effective potential to whose critical points permanent rotations or regular precessions of the tippe top correspond. Tippe top inversion is possible for a sufficiently large initial angular velocity under the condition that spinning with the lowest position of the center of gravity is unstable, spinning with the highest position of the center of gravity is stable, and that there are no precessions. Cases are found in which there is no inversion in the absence of vibrations, but it can be brought about by a suitable choice of the mean value of the squared velocity of the base. In particular, this type includes a ball with a spherical cavity filled with a denser substance.

Dependence of added mass on cylinder cross-sectional geometry and orientation

This paper presents an experimental study on the added masses associated with the cylinders of different cross-sectional geometries (circular, square and rectangular of side ratio of 4) and angles of attack (θ = 0°- 90°) with respect to incident flow. Two fluid media are considered, i.e. water and paraffin oil. The added mass is investigated from three different perspectives. Firstly, the added mass is estimated from a shift in the oscillation frequency of the cylinder in water or paraffin oil from that in still air, referred to as the average added mass. Thus defined added mass is dependent on both cylinder cross-sectional geometry and orientation but is independent of the fluid medium. The average added mass decreases from 1.52 at θ = 0°to a minimum of 1.20 at θ = 45°for the square cylinder but grows monotonically from 0.55 at θ = 0°to 4.90 at θ = 90°for the rectangular cylinder. Secondly, the added mass is calculated from the equation of structural dynamics. This added mass decreases linearly with the decreasing oscillation amplitude, thus called the amplitude-dependent added mass. Thirdly, the amplitude-dependent added mass is reduced to the unique added mass in the absence of vibration. The unique added mass is in general smaller (< 11.3% depending on geometry and θ) than the average added mass but displays a similar dependence on the cylinder cross-sectional geometry and θ.

Hydrodynamic pressure upon elements of the shutter with flexible working bodies

For automatic control of the water level in the part of the channel in front of the hydraulic structure, a hydraulic automatic water level controller was proposed. Its main element is a shutter with flexible working elements, consisting of a reservoir formed by a shield for draining water from the channel and flexible cloth. To ensure stable operation without vibration, experimental studies of this shutter with a spillway in the form of a non-vacuum profile were carried out. These studies were carried out by the method of physical modeling of the model and nature in an experimental setup. The aim of the study was to determine the hydrodynamic pressure acting on this shutter, the forces of hydrodynamic pressure, and the centers of application of these forces to the shutter in the form of a non-vacuum profile. Studies have shown positive hydrodynamic pressure on the spillway of the shutter, the absence of vibration, the stability of the shutter. The obtained dependences for determining the forces and centers of application of hydrodynamic pressure forces to the elements of the spillway part of the shutter allow us to calculate this shutter

Heat Transfer by Steady Streaming in a Horizontal Annulus with Inner Heating at Boundary Vibration

Convection and heat transfer are studied experimentally in a horizontal annulus, the outer wall of which is formed by an elastic silicone tube, and the inner one – by a copper cylindrical heat exchanger. The working volume is filled with a viscous fluid. T he temperature of the outer boundary is kept constant. At the inner boundary, a constant heat generation power is maintained. The elastic outer wall is driven in a periodic motion by two linear motors, installed symmetrically to the left and to the right of the container and performing synchronous oscillations. Thermal measurements are carried out at steady state temperature. In the absence of vibrations, free convection is observed. Vibrations lead to the generation of steady averaged flows in the form of a system of eight pairs of rolls, parallel to the cylinder axis. Vibrational convection enhances heat transfer across the annulus. The structure of steady flows and the rate of heat transfer are determined by the interaction between two convective mechanisms.

Get off my back: vibrational assessment of homeowner strength.

Animals may use a variety of sensory modalities to assess ownership and resource-holding potential (RHP). However, few studies have experimentally tested whether animals can assess these key variables through a purely vibrational modality, exclusively involving substrate-borne vibrations. Here we studied social terrestrial hermit crabs ( Coenobita compressus), where competitors assess homeowners by climbing on top of a solid external structure-an architecturally remodelled shell home, inside of which the owner then produces vibrations. In the field, we used a miniature vibratory device, hidden within an empty shell, to experimentally simulate a 'phantom owner', with variable amplitudes of vibration representing different levels of homeowner strength. We found that assessors could use these vibrations to deduce the owner's RHP: for strong vibrations (indicative of a high RHP owner) assessors were least likely to escalate the conflict; for weak vibrations (indicative of a low RHP owner) assessors showed intermediate escalation; and in the absence of vibration (indicative of an extremely weak or absent owner) assessors were most likely to escalate. These results reveal that animals can assess homeowner strength based solely on substrate vibrations, thereby making important decisions about whether to escalate social conflicts over property.