Precise Rotation Research Articles

3D-printed acoustic metasurface with encapsulated micro-air-bubbles for frequency-selective manipulation.

Acoustic waves provide an effective method for object manipulation in microfluidics, often requiring high-frequency ultrasound in the megahertz range when directly handling microsized objects, which can be costly. Micro-air-bubbles in water offer a solution toward low-cost technologies using low-frequency acoustic waves. Owing to their high compressibility and low elastic modulus, these bubbles can exhibit significant expansion and contraction in response to even kilohertz acoustic waves, leading to resonances with frequencies determined and tuned by air-bubble size. The resonances amplify vibrational amplitude and generate localized turbulence, enabling selective, non-invasive, and high-precision manipulation of microsized objects. However, conventional bubble formation relies on the shear force of the liquid flow and bubble surface tension, facing challenges of instability and random vibration that can impair manipulation precision and performance. To address these issues, we propose a coupled vibration structure with 3D-printed circular microsized air holes encapsulated by a PDMS film. These airholes act as artificial micro-air-bubbles, with their expansion and contraction stabilized by acoustic hard boundaries. The PDMS film further regulates vibration modes through the interaction between air movement and the film's vibration, eliminating randomness. Compared to conventional air-bubbles held by surface tension, these artificial air-bubbles are mechanically stable, allowing for enhanced gas volume changes and stronger forces for object manipulation. We experimentally confirm the stable vibration modes and their frequency-dependent behavior using laser Doppler vibrometry. Precise aggregation, rotation, and separation of micro-objects are demonstrated by adjusting the film's vibration mode. Furthermore, we propose a metasurface design featuring a multi-size microbubble array for frequency-selective manipulation, enabling flexible control of sample trajectory by changing the exciting frequency of an embedded piezoelectric transducer. Our low-frequency acoustic metasurface device offers a versatile, cost-effective solution for drug screening and automated sample handling.

Design, Simulation, and Fabrication of a Harmonic Drive Stepper Motor for Precise Rotation Application

Design, Simulation, and Fabrication of a Harmonic Drive Stepper Motor for Precise Rotation Application

Open Photonics: An integrated approach for building a 3D-printed motorized rotation stage system

In the context of experimental optics- and photonics-research, motorized, high-precision rotation stages are an integral part of almost every laboratory setup. Nevertheless, their availability in the laboratory is limited due to the relatively high acquisition costs in the range of several 1000€ and is often supplemented by manual rotation stages. If only a single sample is to be analyzed repeatedly at two different angles or the polarization of a laser source is to be rotated, this approach is understandable. Yet, in the context of automation and the associated gain in measurement time, cost-effective and precise rotation stages designed for the use of optics are lacking.We present a low-cost alternative of a motorized high precision rotation stage system. The design is based on a combination of 3D-printed components, which form the monolithic mechanical framework, and a stepper motor controlled by an ESP32 based microcontroller. By coupling the motor and rotation unit via a toothed belt, backlash is minimized and at the same time high positioning accuracy can be achieved. Finally, the implementation of remote procedure calls for serial communication and the utilization of a physical home switch and incremental encoder complete the desired feature set of an integrated system for laboratory setups. The total costs can thus be reduced to less than 100€ without significantly restricting the performance criteria.

Wavefront rotator with near-zero mean polarization change

A K-mirror is a device that rotates the wavefront of an incident optical field. It has recently gained prominence over the Dove prism, another commonly used wavefront rotator, due to the fact that while a K-mirror has several controls for adjusting the internal reflections, a Dove prism is made of a single glass element with no additional control. Thus, one can obtain much lower angular deviations of transmitting wavefronts using a K-mirror than with a Dove prism. However, the accompanying polarization changes in the transmitted field due to rotation persist even in the commercially available K-mirrors. A recent theoretical work [Appl. Opt. 61, 8302 (2022)APOPAI0003-693510.1364/AO.472543] shows that it is possible to optimize the base angle of a K-mirror for a given refractive index such that the accompanying polarization changes are minimum. In contrast, we show in this paper that by optimizing the refractive index it is possible to design a K-mirror at any given base angle and with any given value for the mean polarization change, including near-zero values. Furthermore, we experimentally demonstrate a K-mirror with an order-of-magnitude lower mean polarization change than that of the commercially available K-mirrors. This can have important practical implications for OAM-based applications that require precise wavefront rotation control.

Discovery of a Shock-compressed Magnetic Field in the Northwestern Rim of the Young Supernova Remnant RX J1713.7–3946 with X-Ray Polarimetry

Supernova remnants (SNRs) provide insights into cosmic-ray acceleration and magnetic field dynamics at shock fronts. Recent X-ray polarimetric measurements by the Imaging X-ray Polarimetry Explorer (IXPE) have revealed radial magnetic fields near particle acceleration sites in young SNRs, including Cassiopeia A, Tycho, and SN 1006. We present here the spatially resolved IXPE X-ray polarimetric observation of the northwestern rim of SNR RX J1713.7–3946. For the first time, our analysis shows that the magnetic field in the particle acceleration sites of this SNR is oriented tangentially with respect to the shock front. Because of the lack of precise Faraday rotation measurements in the radio band, this was not possible before. The average measured polarization degree (PD) of the synchrotron emission is 12.5% ± 3.3%, lower than the one measured by IXPE in SN 1006, comparable to the Tycho one, but notably higher than the one in Cassiopeia A. On subparsec scales, localized patches within RX J1713.7–3946 display a PD of up to 41.5% ± 9.5%. These results are compatible with a shock-compressed magnetic field. However, in order to explain the observed PD, either the presence of a radial net magnetic field upstream of the shock or partial reisotropization of the turbulence downstream by radial magnetohydrodynamical instabilities can be invoked. From comparison of PD and magnetic field distribution with γ-rays and 12CO data, our results provide new inputs in favor of a leptonic origin of the γ-ray emission.

Wide Linearity Range 3D Magnetic Sensor and Angular Position Detector Based on a Single FePt Spin-Orbit Torque Device.

Three-dimensional (3D) vector magnetic sensors play a significant role in a variety of industries, especially in the automotive industry, which enables the control of precise position, angle, and rotation of motion elements. Traditional 3D magnetic sensors integrate multiple sensors with their sensing orientations along the three coordinate axes, leading to a large size and inevitable nonorthogonal misalignment. Here, we demonstrate a wide linearity range 3D magnetic sensor utilizing a single L10-FePt Hall-bar device, whose sensitivity is 291 VA-1 T-1 in the z-axis and 27 VA-1 T-1 in the in-plane axis. Based on the spin-orbit torque-dominated magnetization reversal, the linear response of anomalous Hall resistance within a large linear range (±200 Oe) for the x, y, and z components of magnetic fields has been obtained, respectively. Typically, it exhibits a relatively lower magnetic noise level of 7.9 nV at 1 Hz than previous results, improving measurement resolution at the low frequency. Furthermore, we provide a straightforward approach for noncontact angular position detection based on a single Hall-bar device, which shows great potential for application in rotational motion control.

High precision vertical angle measurement system for calibration of various angle sensors and instruments

A versatile measurement system was developed for efficient calibration of vertical angle sensors or instruments. The vertical angle measurement system (VAMS) comprises a precision rotation stage, a controller, and additional components for fixing an angle sensor or detecting angular deviation. It can generate single-axis rotation within ±120° range with a resolution of 0.01″. To detect angular deviation in angle instrument calibration, a special miniature autocollimator was developed using a diffractive optical element, providing high-precision angle measurement even with the short focal length of its lens. The performance of the VAMS was evaluated by comparing face angles of two optical polygons, measured by the VAMS and other reference systems. As typical exemplary calibrations, an electronic level and vertical angle readouts of a total station were calibrated with expanded uncertainty (k = 2) of 0.19″ and 0.51″, respectively.

Measuring the profile of aircraft engine blades using spectral confocal sensors

The geometric parameters of aircraft engine blades need to be precisely measured to ensure the quality of the blades for the normal operation of aircraft engines. This study aims to address the challenges of existing measurement systems in balancing efficiency, accuracy, and completeness. Additionally, it aims to enhance the accuracy and robustness of the algorithm for extracting blade profile characteristic parameters. In this paper, a spectral confocal sensor is employed to establish a blade profile measurement system. The design includes a probe sampling strategy, and a standard ball is used to calibrate the sensor probe’s light emission direction and the precise rotation center of the turntable. The paper proposes the use of methods such as partition search algorithm, binary search, and curvature segmentation to process point cloud data of blade body and tenon. We have conducted experimental measurements on the blades of an aircraft engine. The acquired three-dimensional point cloud data of multiple sets of blade cross-sections and dovetail sections were processed. After calculation, the maximum measurement errors for chord length, maximum blade thickness, tenon width, bottom height, top angle, and bottom angle are −0.0036 mm, −0.00721 mm, −0.0102 mm, −0.00928 mm, 0.0086°, and −0.0058°, respectively. This process validates the effectiveness of the proposed method and has high measurement accuracy. Compared with the CMM method, this method is more accurate in measuring small pits and large curvature micro surfaces, with higher measurement integrity and higher measurement efficiency.

Friction Characteristics and Lubrication Properties of Spherical Hinge Structure of Swivel Bridge

A spherical hinge structure is a key swivel bridge element that must be considered when evaluating friction characteristics and lubrication properties to meet the rotation requirement. Polytetrafluoroethylene (PTFE)-based spherical hinge sliders and lubrication coating have been employed for over 20 years, but with the growing tonnage of swivel bridge construction, their capacity to accommodate the required lubrication properties can be exceeded. In this manuscript, the optimal friction coefficient of the spherical hinge is obtained through the finite element analysis method. Four lubrication coatings and four spherical hinge sliders are prepared and tested through a self-developed rotation friction coefficient test, four-ball machine test, dynamic shear rheological test, and compression and shear performance test to evaluate the lubrication and friction properties of the spherical hinge structure. The results of the finite element analysis show that the optimum rotation friction coefficient of the spherical hinge structure is 0.031–1.131. The test results illustrate that the friction coefficient, wear scar diameter, maximum non-seize load, phase transition point, and thixotropic ring area of graphene lubrication coating are 0.065, 0.79 mm, 426 N, 14.6%, and 64,878 Pa/s. The graphene lubrication coating has different degrees of improvement compared with conventional polytetrafluoroethylene lubrication coating, showing more excellent lubrication properties, bearing capacity, thixotropy, and structural strength. Compressive and shear tests demonstrate that polyether ether ketone (PEEK) has good compressive and shear mechanical properties. The maximum compressive stress of PEEK is 87.7% higher than conventional PTFE, and the shear strength of PEEK is 6.07 times higher than that of PTFE. The research results can provide significantly greater wear resistance and a lower friction coefficient of the spherical hinge structure, leading to lower traction energy consumption and ensuring smooth and precise bridge rotation.

High Precision Positioning and Rotation Angle Estimation of a Flatbed Truck Based on BDS and Vision.

Centimeter-level localization and precise rotation angle estimation for flatbed trucks pose significant challenges in unmanned forklift automated loading scenarios. To address this issue, the study proposed a method for high-precision positioning and rotation angle estimation of flatbed trucks using the BeiDou Navigation Satellite System (BDS) and vision technology. First, an unmanned forklift equipped with a Time-of-Flight (ToF) camera and a dual-antenna mobile receiver for BDS positioning collected depth images and localization data near the front and rear endpoints of the flatbed. The Deep Dual-Resolution Network-23-slim (DDRNet-23-slim) model was used to segment the flatbed from the depth image and extract the straight lines at the edges of the flatbed using the Hough transform. The algorithm then computed the set of intersection points of the lines. A neighborhood feature vector was designed to identify the endpoint of a flatbed from a set of intersection points using feature screening. Finally, the relative coordinates of the endpoints were converted to a customized forklift navigation coordinate system by BDS positioning. A rotation angle estimation was then performed using the endpoints at the front and rear. Experiments showed that the endpoint positioning error was less than 3 cm, and the rotation angle estimation error was less than 0.3°, which verified the validity and reliability of the method.

Bidirectional and Stepwise Rotation of Cells and Particles Using Induced Charge Electroosmosis Vortexes.

The rotation of cells is of significant importance in various applications including bioimaging, biophysical analysis and microsurgery. Current methods usually require complicated fabrication processes. Herein, we proposed an induced charged electroosmosis (ICEO) based on a chip manipulation method for rotating cells. Under an AC electric field, symmetric ICEO flow microvortexes formed above the electrode surface can be used to trap and rotate cells. We have discussed the impact of ICEO and dielectrophoresis (DEP) under the experimental conditions. The capabilities of our method have been tested by investigating the precise rotation of yeast cells and K562 cells in a controllable manner. By adjusting the position of cells, the rotation direction can be changed based on the asymmetric ICEO microvortexes via applying a gate voltage to the gate electrode. Additionally, by applying a pulsed signal instead of a continuous signal, we can also precisely and flexibly rotate cells in a stepwise way. Our ICEO-based rotational manipulation method is an easy to use, biocompatible and low-cost technique, allowing rotation regardless of optical, magnetic or acoustic properties of the sample.

Angle-resolved X-ray emission spectroscopy facility realized by an innovative spectrometer rotation mechanism at SPring-8 BL07LSU.

The X-ray emission spectrometer at SPring-8 BL07LSU has recently been upgraded with advanced modifications that enable the rotation of the spectrometer with respect to the scattering angle. This major upgrade allows the scattering angle to be flexibly changed within the range of 45-135°, which considerably simplifies the measurement of angle-resolved X-ray emission spectroscopy. To accomplish the rotation system, a sophisticated sample chamber and a highly precise spectrometer rotation mechanism have been developed. The sample chamber has a specially designed combination of three rotary stages that can smoothly move the connection flange along the wide scattering angle without breaking the vacuum. In addition, the spectrometer is rotated by sliding on a flat metal surface, ensuring exceptionally high accuracy in rotation and eliminating the need for any further adjustments during rotation. A control system that integrates the sample chamber and rotation mechanism to automate the measurement of angle-resolved X-ray emission spectroscopy has also been developed. This automation substantially streamlines the process of measuring angle-resolved spectra, making it far easier than ever before. Furthermore, the upgraded X-ray emission spectrometer can now also be utilized in diffraction experiments, providing even greater versatility to our research capabilities.

Enhancing Aluminum-Based Composite Manufacturing: Leveraging Si3N4 Reinforcement via Friction Stir Process

In the realm of composite manufacturing, this study delves into the innovative approach of enhancing Aluminum-Based Composite Manufacturing through Si3N4 Reinforcement leveraged via Friction Stir Process (FSP). The FSP technique, executed with precision using a vertical milling machine, intricately fabricates composite materials with unparalleled properties. Meticulously chosen parameters including pin diameter, tool tilt angle, and tool profile, coupled with precise tool traversal and rotation, define the operation. The composite substrate, composed of AA 2024, undergoes stringent cleanliness protocols before Si3N4 powders are strategically placed into a designated groove on the titanium surface for processing. Microscopic examination reveals the uniform dispersion of Si3N4 particles within the aluminum matrix, profoundly enhancing mechanical properties. The tensile strength experiences a remarkable 21.45% improvement, while hardness witnesses a significant enhancement of 36.9%. Additionally, fatigue strength is notably improved by 24.12%, and wear resistance sees a substantial boost of 30.44% following Si3N4 nanoparticle integration via FSP.

Optimal Model-Free Finite-Time Control Based on Terminal Sliding Mode for a Coaxial Rotor

This study focuses on addressing the tracking control problem for a coaxial unmanned aerial vehicle (UAV) without any prior knowledge of its dynamic model. To overcome the limitations of model-based control, a model-free approach based on terminal sliding mode control is proposed for achieving precise position and rotation tracking. The terminal sliding mode technique is utilized to approximate the unknown nonlinear model of the system, while the global stability with finite-time convergence of the overall system is guaranteed using the Lyapunov theory. Additionally, the selection of control parameters is addressed by incorporating the accelerated particle swarm optimization (APSO) algorithm. Finally, numerical simulation tests are provided to demonstrate the effectiveness and feasibility of the proposed design approach, which demonstrates the capability of the model-free control approach to achieve accurate tracking control even without prior knowledge of the system’s dynamic model.

Optofluidic-based cell multi-axis controllable rotation and 3D surface imaging

The controlled rotation of individual cells plays a crucial role in enabling three-dimensional multi-angle observation of cellular structure, function, and dynamic processes. Reported cell rotation techniques often struggle to strike a balance between high precision and simple control, and they exhibit limited control flexibility, typically achieving only uniaxial cell rotation. In this study, we propose a cell rotation technique in three dimensions based on optofluidics, which utilizes optical tweezers to immobilize the cell and exploits the asymmetry of the surrounding flow to drive cell rotation. By adjusting the focal position of the optical tweezers, cells can be positioned within various flow profiles, enabling control of the rotation speed, rotation direction, and rotation axis of cells. This approach simplifies the manipulation procedure, achieving desirable control precision and greater rotation flexibility. Using our approach, multi-angle surface imaging projections of target cells can be rapidly obtained, followed by capturing the cell contour data from the images. By combining the cell contour data with corresponding angular position information, we have reconstructed the 3D surface of the target cell. We have employed this technique in experiments for the analysis of red blood cell morphology. Based on the constructed 3D surface images of diverse-shaped red blood cells, we quantified structural parameters including cell surface area, volume, sphericity, and surface roughness, which demonstrates the potential application of this cell rotation technique for cellular morphological analysis.

HACK: Learning a Parametric Head and Neck Model for High-fidelity Animation

Significant advancements have been made in developing parametric models for digital humans, with various approaches concentrating on parts such as the human body, hand, or face. Nevertheless, connectors such as the neck have been overlooked in these models, with rich anatomical priors often unutilized. In this paper, we introduce HACK (Head-And-neCK), a novel parametric model for constructing the head and cervical region of digital humans. Our model seeks to disentangle the full spectrum of neck and larynx motions, facial expressions, and appearance variations, providing personalized and anatomically consistent controls, particularly for the neck regions. To build our HACK model, we acquire a comprehensive multi-modal dataset of the head and neck under various facial expressions. We employ a 3D ultrasound imaging scheme to extract the inner biomechanical structures, namely the precise 3D rotation information of the seven vertebrae of the cervical spine. We then adopt a multi-view photometric approach to capture the geometry and physically-based textures of diverse subjects, who exhibit a diverse range of static expressions as well as sequential head-and-neck movements. Using the multi-modal dataset, we train the parametric HACK model by separating the 3D head and neck depiction into various shape, pose, expression, and larynx blendshapes from the neutral expression and the rest skeletal pose. We adopt an anatomically-consistent skeletal design for the cervical region, and the expression is linked to facial action units for artist-friendly controls. We also propose to optimize the mapping from the identical shape space to the PCA spaces of personalized blendshapes to augment the pose and expression blendshapes, providing personalized properties within the framework of the generic model. Furthermore, we use larynx blendshapes to accurately control the larynx deformation and force the larynx slicing motions along the vertical direction in the UV-space for precise modeling of the larynx beneath the neck skin. HACK addresses the head and neck as a unified entity, offering more accurate and expressive controls, with a new level of realism, particularly for the neck regions. This approach has significant benefits for numerous applications, including geometric fitting and animation, and enables inter-correlation analysis between head and neck for fine-grained motion synthesis and transfer.

Radio timing constraints on the mass of the binary pulsar PSR J1528−3146

Context. PSR J1528−3146 is a 60.8 ms pulsar orbiting a heavy white dwarf (WD) companion, with an orbital period of 3.18 d. The pulsar was discovered in the early 2000 s in a survey at 1.4 GHz of intermediate Galactic latitudes conducted with the Parkes radio telescope. The initial timing analysis of PSR J1528−3146, using data recorded from 2001 and 2004, did not reveal any relativistic perturbations to the orbit of the pulsar or to the propagation of its pulses. However, with an orbital eccentricity of ∼0.0002 and a large companion mass on the order of 1 M⊙, this system has been deemed likely to exhibit measurable perturbations. Aims. This work is aimed at characterizing the pulsar’s astrometric, spin, and orbital parameters by analyzing timing measurements conducted at the Parkes, MeerKAT, and Nançay radio telescopes over nearly two decades. The measurement of post-Keplerian perturbations to the pulsar’s orbit can be used to constrain the masses of the two component stars of the binary and, in turn, to offer insights into the history of the system. Methods. We analyzed timing data from the Parkes, MeerKAT, and Nançay radio telescopes collected over about 16 yr, obtaining a precise rotation ephemeris for PSR J1528−3146. A Bayesian analysis of the timing data was carried out to constrain the masses of the two components and the orientation of the orbit. We further analyzed the polarization properties of the pulsar to constrain the orientation of the magnetic axis and of the line of sight with respect to the spin axis. Results. We measured a significant rate of advance of periastron, for the first time, and we set constraints on the Shapiro delay in the system and on the rate of change of the projected semi-major axis of the pulsar’s orbit. The Bayesian analysis yielded measurements for the pulsar and companion masses of Mp = 1.61−0.13+0.14 M⊙ and Mc = 1.33−0.07+0.08 M⊙ (68% C.L.), respectively, confirming that the companion is indeed massive. This companion mass as well as other characteristics of PSR J1528−3146 indicate that this pulsar is very similar to PSR J2222−0137, a 32.8 ms pulsar orbiting a WD whose heavy mass (∼1.32 M⊙) has been considered unique among pulsar-WD systems until now. Our measurements suggest common evolutionary scenarios for PSRs J1528−3146 and J2222−0137.

Development of a stator-rotor integrated piezoelectric actuator for precise joint rotation of the robotic arm

Piezoelectric rotary actuators are widely used for their high precision and large torque in various fields, such as optical engineering and aerospace. However, traditional piezoelectric rotary motors have a complex structure, requiring separate stator and rotor fixing devices, and they have a low space utilization rate, making them unsuitable for driving joint rotation of robotic arms. To address these issues, a novel stator-rotor integrated piezoelectric actuator is proposed in this paper, which uses the piezoelectric vibrator as both the driving vibration source and the rotor, simplifying the overall structure of the rotary actuator. By using in-plane longitudinal and out-of-plane bending vibration, the actuator achieves high-precision rotation along the diameter of a circular ring, while also providing a hollow structure for optical fibers and wires. Through parametric scanning finite element analysis, the size parameters of the annular rotor are determined. The contact conditions of stator and rotor is analyzed, and an intermittent contact model between stator and rotor is established. The experimental results show that the prototype motor weighs 52 g, has a rotation speed of 1470 deg/s, can bear a load of 63 mN m, and has a minimum resolution of 72 μrad. This research demonstrates the great potential of this rotating actuator for use in space optical instruments and aerospace applications.

Validation of direct CT measurement of malrotation in femoral neck fractures: A bone model study.

While postoperative malrotation in the subtrochanteric region is a well-known problem, malrotation after osteosynthesis in proximal femoral fractures has not been extensively studied. In this context, many methods for perioperatively assessment of femoral torsion have been described, but none of them is applicable in the basicervical region of the proximal femur. As an important difference in femoral neck fractures, the discontinuous neck fails to serve as a significant "pointer" for measurements and malfunctions to be placed in relation to the condylar plane. Considering postoperative maltorsion at any location as a substantial negative effect on patients' outcome and functional expectations, precise and patient-friendly rotation measurement standards in femoral neck fractures are desired in clinical practice. Recently, a novel computed tomography (CT) based geometric technique was described named "direct measurement" with promising results covering this diagnostic disparity, but still requires validation. Thus, we aimed to validate the previously described technique using a controlled range of displacement in a femoral neck fracture Sawbone® model. A goniometer was designed to set retro- and anteversion of the proximal femur in a reproducible manner. Prospectively, all femurs underwent a CT scan and were measured 3D for displacement. The interclass correlation between the CT measurements and the goniometer measurements was calculated and was found to be very high (1.00, 95% confidence interval: 0.99-1.00; p < 0.001). For the mean of all measurements, the Pearson's correlation was 1.00 (p < 0.001). No significant differences in the measurements of both investigators were observed, with 20° of retroversion not significant (-1.20 ± 1.71; 95% confidence interval: -2.43-0.03; p = 0.054). This CT-based 3D measurement technique may allow for perioperative malrotation assessment in basicervical femoral neck fractures and appears to be feasible in femoral neck fractures when it comes to rare cases of osteosynthesis. Further investigations are still needed to define the thresholds of malrotation provoking functional impairment after osteosynthesis in basicervical femoral neck fractures.

Acoustic rotation of non-spherical micro-objects: Characterization of acoustophoresis and quantification of rotational stability

Acoustic radiation force and torque arising from wave scattering have the potential to perform the biocompatible, contact-free, and precise translation and rotation of micro-objects. Controllable rotation of objects mainly relies on the use of sophisticated transducer arrays, while it is limited by the spatial Rayleigh limitation and would be costly to miniaturize the array for manipulated objects on the micron scale. Here, we make use of the shape asymmetry of an object and achieve micro-object trap and rotation using a simple standing wavefield. The conformal transformation approach is employed to map an axisymmetric, non-spherical object into a sphere, allowing fast analysis for design or real-time computer-controlled manipulation. A low-cost, simple rotational tweezing system is built, which confirms the theoretical prediction that micro-particles are trapped in the pressure nodes and remotely rotated by the action of the actuator boundaries. The rotational dynamics are guided by two stabilization modes, and Lyapunov stability analysis reveals that at least one mode leads to a stable equilibrium state. We demonstrate the significance of our approach in stably and controllably rotating micron-scale objects. The robustness and versatility of the new handy design hold promise for clinical applications and microscopic research such as drug delivery and microsurgery.