Three-dimensional Position Research Articles

Validity of Spatio-Temporal Gait Parameters in Healthy Young Adults Using a Motion-Sensor-Based Gait Analysis System (ORPHE ANALYTICS) during Walking and Running.

Motion sensors are widely used for gait analysis. The validity of commercial gait analysis systems is of great interest because calculating position/angle-level gait parameters potentially produces an error in the integration process of the motion sensor data; moreover, the validity of ORPHE ANALYTICS, a motion-sensor-based gait analysis system, has not yet been examined. We examined the validity of the gait parameters calculated using ORPHE ANALYTICS relative to those calculated using conventional optical motion capture. Nine young adults performed gait tasks on a treadmill at speeds of 2−12 km/h. The three-dimensional position data and acceleration and angular velocity data of the feet were collected. The gait parameters were calculated from motion sensor data using ORPHE ANALYTICS, and optical motion capture data. Intraclass correlation coefficients [ICC(2,1)] were calculated for relative validities. Eight items, namely, stride duration, stride length, stride frequency, stride speed, vertical height, stance phase duration, swing phase duration, and sagittal angleIC exhibited excellent relative validities [ICC(2,1) > 0.9]. In contrast, sagittal angleTO and frontal angleIC demonstrated good [ICC(2,1) = 0.892−0.833] and moderate relative validity [ICC(2,1) = 0.566−0.627], respectively. ORPHE ANALYTICS was found to exhibit excellent relative validities for most gait parameters. These results suggest its feasibility for gait analysis outside the laboratory setting.

Investigation of Medium Range Order Defects in CuxZr100-x (x = 50, 56, 60, 64) Metallic Glasses Using Reverse Monte Carlo Modeling

The identification of glassy defects in amorphous materials is a long-standing but imperative problem which hinders our deep understanding of the structural origin of mechanical behavior in metallic glasses (MGs). Here, a combination of experiments and numerical simulations were used to reconstruct the atomic packing of MGs. Using the integration of synchrotron X-ray diffraction (XRD) datasets, ab initio molecular dynamics simulations, as well as reverse Monte Carlo simulation, we determined the three-dimensional atomic positions of a series of binary MGs CuxZr100-x (x = 50, 56, 60, 64). Then we uncovered the connection of short-range clusters as well as the nature of the medium range order (MRO). It turns out that full icosahedral tend to connect to each other forming the back bones, with dimensions positively correlated with the Cu content. By quantifying the discontinuity of full icosahedral networks, we identified the MRO defects which were found to be highly influenced by the macroscopic chemical contents. Here, the density of MRO defects is growing with the decrease of Cu contents. These results suggest the reason for the stable kinetic properties and good glass forming ability of the Cu64Zr36 system, which is rich in full icosahedral clusters <0,0,12,0> but a lack of MRO defects.

Research on Indoor 3D Positioning Algorithm Based on WiFi Fingerprint

Indoor 3D positioning is useful in multistory buildings, such as shopping malls, libraries, and airports. This study focuses on indoor 3D positioning using wireless access points (AP) in an environment without adding additional hardware facilities in large-scale complex places. The integration of a deep learning algorithm into indoor 3D positioning is studied, and a 3D dynamic positioning model based on temporal fingerprints is proposed. In contrast to the traditional positioning models with a single input, the proposed method uses a sliding time window to build a temporal fingerprint chip as the input of the positioning model to provide abundant information for positioning. Temporal information can be used to distinguish locations with similar fingerprint vectors and to improve the accuracy and robustness of positioning. Moreover, deep learning has been applied for the automatic extraction of spatiotemporal features. A temporal convolutional network (TCN) feature extractor is proposed in this paper, which adopts a causal convolution mechanism, dilated convolution mechanism, and residual connection mechanism and is not limited by the size of the convolution kernel. It is capable of learning hidden information and spatiotemporal relationships from the input features and the extracted spatiotemporal features are connected with a deep neural network (DNN) regressor to fit the complex nonlinear mapping relationship between the features and position coordinates to estimate the 3D position coordinates of the target. Finally, an open-source public dataset was used to verify the performance of the localization algorithm. Experimental results demonstrated the effectiveness of the proposed positioning model and a comparison between the proposed model and existing models proved that the proposed model can provide more accurate three-dimensional position coordinates.

A New Machine Vision Method for Target Detection and Localization of Malleable Iron Pipes: An Experimental Case

Malleable iron pipes are widely used in construction, manufacturing, aerospace, and many other fields. Cast malleable iron pipes need to be treated flat to meet the needs of different shapes and sizes. This process is usually completed manually, which is low efficiency and is subject to potential safety risks. To solve this problem, a machine vision method is proposed to detect and localize malleable iron pipes. Point cloud images of malleable iron pipes are obtained by the Random Sample Consensus (RANSAC) algorithm, and precise matching is completed by the Iterative Closest Point (ICP) algorithm to obtain more accurate positions, so as to realize robot grasping. The grasping experiments of malleable iron pipes with the same and different specifications were carried out using a specially designed experimental platform. The results show that malleable iron pipes can be identified effectively and that the corresponding grasping success rate is more than 85 %. The target detection and localization method can obtain the three-dimensional (3D) position of malleable iron pipes to improve grasping efficiency, which provided a certain theoretical basis and guiding significance to improve production efficiency in practice.

Model-based deconvolution for particle analysis applied to a through-focus series of HAADF-STEM images.

This paper presents an approach for determining the sizes and three-dimensional (3D) positions of nanoparticles from a through-focus series of high-angle annular dark-field scanning transmission electron microscopy images. By assuming spherical particles with uniform density, the sizes and 3D positions can be derived via Wiener deconvolution using a series of kernels prepared by the convolution of the 3D point spread function of the electron beam and the 3D density distribution of spheres with different radii. This process is referred to as a model-based deconvolution. Four 3D datasets with a volume size of 148 × 148 × 560 nm3 were obtained from the four sets of 256 high-angle annular dark-field scanning transmission electron microscopy images of 256 × 256 pixels taken from the same field of view under the through-focus condition. The 3D positions and radii of 14 particles in each 3D dataset were derived using the model-based deconvolution for ∼8 min. The observation errors of the 3D position were estimated as σx ≅ σy ≅ 0.3 nm and σz < 1.6 nm.

Development of Intraoperative Plantar Pressure Measurement System Considering Weight Bearing Axis and Center of Pressure

To prevent postoperative complications in corrective surgery for foot deformities such as hallux valgus and pes planus, it is critical to quantitatively predict the postoperative standing-position plantar pressure distribution during the operation. The authors have previously proposed an intraoperative plantar pressure measurement system (IPPM) that allows for the measurement of a supine patient’s plantar pressure distribution that is equivalent to that in the standing position. This system consists of an IPPM device comprising of a force plate and pressure distribution sensor, an optical three-dimensional position measurement device, a navigation monitor, and a PC. The plantar pressure distribution in the standing position is reproduced by navigating the operator, as he or she presses the IPPM device against the patient’s sole so that the weight-bearing axis (floor reaction force vector) and femoral head center are as close to each other as possible. However, in our previous study, the reproducibility of the standing position plantar pressure distribution was insufficient. Therefore, in the present study, we add a navigational function that can be used to bring the centers of pressure in the standing position and under measurement, as well as to correct the IPPM’s self-weight in the measured force. The improved device was used in an experiment with nine healthy subjects, and the similarity of the plantar pressure distribution in the standing and supine positions was evaluated using normalized cross-correlation, yielding an average of 0.90. Furthermore, in an evaluation experiment with ten orthopedic surgeons, it was observed that using the system reproduced the plantar pressure distribution significantly better than when the system was not used. These results indicate that the present system can predict the plantar pressure distribution in the standing position. We believe that this system can contribute to reducing complications after foot surgery.

Design and Implementation of 3-D Measurement Method for Container Handling Target

In the process of automatic container terminal loading and unloading, the three-dimensional attitude of the container affects the security of loading and unloading operations, so the three-dimensional attitude positioning of the container is very important. In this paper, a visual non-contact measurement method is used to realize the real-time orientation of the three-dimensional attitude of the container. First, the container corner is coarsely positioned by a small-scale deep learning network. Secondly, the precise position of the container keyhole is obtained by the secondary positioning of the container corner through the traditional image processing algorithm, and the container posture is measured in three dimensions by combining the physical motion model of the container during loading and unloading. After testing, unlike previous measurement methods, the measurement accuracy of this method met the requirements of automatic loading and unloading of container terminals, and the measurement time met the requirements of real-time measurement.

Genetics of three-dimensional tooth inclination and angulation in orthodontic patients with Class I Occlusion: A cross-sectional study

This cross-sectional study aimed to utilize quantitative polymerase chain reaction (qPCR) to investigate the influence of genetic variance over teeth inclination and angulation in orthodontic patients with Class I occlusion. DNA was extracted from adolescent patients seeking orthodontic treatment in a single institution (from July 2018 to April 2020), who had CBCTs taken as part of initial standardized records. Patients had permanent dentition, Class I skeletal and dental classifications, with normal vertical and transverse skeletal dimensions, normal incisors inclination, no to mild crowding or spacing. qPCR was performed using genetic markers for candidate genes EPB41, TGFβ3, GHR and PAX9. Three-dimensional teeth inclinations (TI) and angulations (TA) were evaluated using Invivo6 software and correlated with genotypes. Reliability of TI and TA was assessed using intraclass correlation coefficients (ICC). Mixed models and multiple linear regression analyses were used to assess the association between each single nucleotide polymorphisms (SNP) with tooth inclination (TI) and with tooth angulation (TA). The results were evaluated at the significance level of P<0.05. Twenty four adolescent patients with mean age of 13.4±2.4 years were included in the study. ICC showed adequate intra-examiner reliability for TI and TA (0.806<r<0.988, P<0.001). Multiple linear regression analysis showed a significant association between TI and homozygous-T polymorphism for PAX9 (P=0.028) and homozygous-G polymorphism for GHR (P=0.028). Also, a significant association between TA and homozygous-A polymorphism for EPB41 (P=0.019) and homozygous-G polymorphism for GHR (P=0.001) was evident. Autosomal recessive patterns of inheritance for PAX9 and GHR with TI and for EPB41 and GHR with TA were shown. This study offers insight toward the hierarchical nature of epigenetic interactions between heredity and the environment in determining the three-dimensional positions of teeth in orthodontic patients with Class I occlusion.

Comparison of skin and shoe marker placement on metatarsophalangeal joint kinematics and kinetics during running

This study investigated the effects of marker placement (skin- vs shoe-mounted) on metatarsophalangeal joint (MTP) kinematics and kinetics during running. Fifteen trained men ran on a 15-m track at 10 and 13 km/h with three (low, standard and high stiffness) shoe longitudinal bending stiffnesses (LBS). Reflective markers were fixed on the shoe upper, and on the skin using holes cut in the shoe. Three-dimensional marker positions and ground reaction forces were recorded at 200 and 2000 Hz, respectively. Kinematic and kinetic parameters were analyzed using one-dimensional metrics (statistical parametric mapping). MTP joint was less dorsiflexed at midstance ([57% to 100%] of braking phase and [0% to 48%] of pushing phase), and the MTP joint plantarflexion moment was higher ([22% to 55%] of pushing phase) with the shoe markerset in comparison with the skin markerset. The effect of LBS on MTP angle was found to be significant for a larger percentage of each stride using the shoe markerset compared to the skin markerset. However, the effect of LBS on plantarflexion moment was significant with the shoe markerset only. The effect of running speed on MTP angle was significant for a larger percentage of each stride with the skin markerset. This study demonstrates that the placement of markers influences the measurement of MTP kinematics and kinetics and that these effects are mediated by other variables such as LBS or running speed. It is concluded that the shoe markerset does not fully reflect the movement of the MTP joint.

Three-dimensional position changes of unopposed molars before implant rehabilitation: a short-term retrospective cohort analysis

ObjectiveTo investigate the spatial changes of unopposed molars within the period between the antagonist extraction and the final implant restoration using data from cone beam computed tomography.MethodsA total of 59 patients with 68 unopposed molars were included in this study. Three-dimensional models reconstructed from cone beam computed tomography data before and after loss of the antagonist were superimposed to measure the spatial changes. The overeruption and tipping of target teeth were calculated by coordinate values.ResultsThe result of overeruption over the study period (9.2 ± 4.3 months) was expressed by two values: the mean overeruption of molar cups (0.432 mm) and the maximum overeruption of cusps (0.753 mm), which were statistically significant compared to the baseline level (p < 0.001). The average tipping was 1.717 degrees in the buccal direction.ConclusionsUnopposed molars displayed overeruption throughout the study period (9.2 ± 4.3 months), which indicates that the clinicians should pay attention to the possibilities of overeruption and make appropriate interventions in their clinical practice. The establishment of three-dimensional measuring methods using cone beam computed tomography data helps analyze spatial changes.

Multivehicle 3D Cooperative Positioning Algorithm Based on Information Geometric Probability Fusion of GNSS/Wireless Station Navigation

With the rapid development of large urban agglomerations and the increasing complexity of urban roads, the high-precision positioning of vehicles has become the cornerstone for the application of vehicle core technologies such as automatic driving. The real-time positioning accuracy of satellite navigation is easily affected by urban canyons, and its stability is poor; thus, how to use the information of the internet of vehicles to achieve satellite navigation fusion has become a difficult problem of multivehicle cooperative positioning. Aiming at this problem, this paper proposes a multivehicle 3D cooperative positioning algorithm based on information geometric probability fusion of GNSS/wireless station navigation (MVCP-GW), which creatively converts various navigation source information into an information geometric probability model, unifies navigation information time–frequency parameters, and reduces the impact of sudden error. Combined with the Kullback–Leibler algorithm (KLA) fusion method, it breaks off the shackles of the probabilistic two-dimensional model and achieves multivehicle three-dimensional cooperative positioning. Compared with the existing cooperative positioning algorithms in the performance of accuracy stability, applicability, obstruction scenarios, and physical verification, the simulation results and physical verification show that the MVCP-GW algorithm can effectively improve real-time vehicle positioning and the stability of vehicle positioning, as well as resist the impact of obstructed environments.

Astrometric observations of water maser sources toward the Galactic Center with VLBI

AbstractThe Central Molecular Zone (CMZ) in the Galactic Center region shows outstanding non-circular motion unlike the Galactic disk. While several models describing this non-circular motion have been proposed, a uniform kinematic model of the CMZ orbit has not yet emerged. To uncover the dynamics of the Galactic center region, we conducted VLBI astrometric observations of 22GHz water maser sources towards the Galactic center using VERA. By measuring parallaxes and proper motions, we can determine whether each source is actually located in the CMZ or not, and identify the three-dimensional positions and velocities in the non-circular orbit if the source is indeed located in the CMZ. We present the results of our astrometric study for several maser sources associated with molecular clouds towards the Galactic center. The astrometric observations toward Sgr B2(M) indicated that Sgr B2 complex is moving toward the positive Galactic longitude relative to Sgr A*.

A New Intraoral Six-Degrees-of-Freedom Jaw Movement Tracking Method Using Magnetic Fingerprints.

We proposed a novel jaw movement tracking method that can measure in six degrees of freedom. The magnetic field generated by a permanent magnet paired with a small, low-power-consumption Hall effect magnetic sensor is used to estimate the relative distance between two objects-in this instance, the lower and upper jaws. By installing a microelectromechanical system (MEMS) orientation sensor in the device, we developed a mouthpiece-type sensing device that can measure voluntary mandibular movements in three-dimensional orientation and position. An evaluation of individuals wearing this device demonstrated its ability to measure mandibular movement with an accuracy of approximately 3 mm. Using the movement recording feature with six degrees of freedom also enabled the evaluation of an individual's jaw movements over time in three dimensions. In this method, all sensors are built onto the mouthpiece and the sensing is completed in the oral cavity. It does not require the fixation of a large-scale device to the head or of a jig to the teeth, unlike existing mandibular movement tracking devices. These novel features are expected to increase the accessibility of routine measurements of natural jaw movement, unrestricted by an individual's physiological movement and posture.

Sub-voxel identification of gamma-ray interaction positions within a pixelated CZT detector through signal analysis

Cadmium zinc telluride (CZT) detectors are well suited for use in gamma-imaging applications thanks to their room-temperature operation, excellent energy resolution, and three-dimensional sensitivity to positions of gamma-ray interactions. In many of these applications, the position resolution with which gamma-interactions can be determined is crucial for high quality imaging. Finer pixelisation may provide improved position resolution but at the cost of increased fabrication cost and degradation of spectral performance. This work sets out to instead investigate and quantify the three-dimensional position resolution achievable using pulse shape analysis applied to digital signals, arising from interactions in a CZT detector pixelated into 2 × 2 × 5 mm3 voxels. The signal response of a 3 × 3 pixel cluster has been characterised as a function of gamma-ray interaction position using collimated 57Co and 137Cs sources. Simple pulse shape analysis algorithms using the transient image and charge collection signals have been developed and applied to achieve a sub-voxel position resolution of better than 0.65 × 0.69 × 1.26 mm3 at 122 keV and of 1.06 mm through 5 mm depth at 662 keV, not accounting for divergence of the collimated beam used to evaluate performance. Assessment of the contribution of the diverging gamma-beam placed a lower bound on the achievable positions resolution in 5 mm thickness at 122 keV of 290μm.

3D Visible Light-Based Indoor Positioning System Using Two-Stage Neural Network (TSNN) and Received Intensity Selective Enhancement (RISE) to Alleviate Light Non-Overlap Zones.

The high precision three-dimensional (3D) visible light-based indoor positioning (VLIP) systems have gained much attention recently for people or robot navigation, access tracking, etc. In this work, we put forward and present the first demonstration, up to the authors' knowledge, of a 3D VLIP system utilizing a two-stage neural network (TSNN) model. The positioning performance would degrade when the distance between the light emitting diode (LED) plane and the receiver (Rx) plane increases; however, because of the finite LED field-of-view (FOV), light non-overlap zones are created. These light non-overlap zones will produce high positioning error particularly for the 3D VLIP systems. Here, we also propose and demonstrate the Received-Intensity-Selective-Enhancement scheme, known as RISE, to alleviate the light non-overlap zones in the VLIP system. In a practical test-room with dimensions of 200 × 150 × 300 cm3, the experimental results show that the mean errors in the training and testing data sets are reduced by 54.1% and 27.9% when using the TSNN model with RISE in the z-direction, and they are reduced by 39.1% and 37.8% in the xy-direction, respectively, when comparing that with using a one stage NN model only. At the cumulative distribution function (CDF) P90, the TSNN model with RISE can reduce the errors by 36.78% when compared with that in the one stage NN model.

Identification of non-dimensional density distribution of concrete structures based on self-attention using hammering response data

The aging of concrete structures has become a serious problem in Japan, and periodic maintenance is essential for preventing accidents caused by structural aging. In this study, a method for estimating defects in concrete using data from hammering tests on a concrete plate using machine learning was developed. A neural network based on self-attention (SAN) to estimate the three-dimensional position and size of the defects was constructed. Moreover, a dataset was created from the topology of the internal defects and the acceleration response waveform when a concrete plate was struck. The entire plate was represented as a non-dimensional density matrix. The SAN used scalograms of the acceleration responses as the input. Furthermore, two types of data augmentation (‘Flip’ and ‘Rotate’) were proposed. The use of both data augmentation techniques achieved the highest accuracy. By setting an appropriate number of rotations, the model was able to estimate all defects in the dataset.

Robot–patient registration for optical tracker-free robotic fracture reduction surgery

Background and objectiveImage-guided robotic surgery for fracture reduction is a medical procedure in which surgeons control a surgical robot to align the fractured bones by using a navigation system that shows the rotation and distance of bone movement. In such robotic surgeries, it is necessary to estimate the relationship between the robot and patient (bone), a task known as robot–patient registration, to realize the navigation. Through the registration, a fracture state in real-world can be simulated in virtual space of the navigation system. MethodsThis paper proposes an approach to realize robot–patient registration for an optical-tracker-free robotic fracture-reduction system. Instead of the optical tracker which is a three-dimensional position localizer, X-ray images are used to realize the robot–patient registration, combining the relationship of both the robot and patient with regards to C-arm. The proposed method consists of two steps of registration, where initial registration is followed by refined registration which adopts particle swarm optimization with the minimum cross-reprojection error based on bidirectional X-ray images. To address the unrecognizable features due to interference between the robot and bone, we also developed attachable robot features. The allocated robot features could be clearly extracted from the X-ray images, and precise registration could be realized through the particle swarm optimization. ResultsThe proposed method was evaluated in phantom and ex-vivo experiments involving a caprine cadaver. For the phantom experiments, the average translational and rotational errors were 1.88 mm and 2.45°, respectively, and the corresponding errors in the ex vivo experiments were 2.64 mm and 3.32° The results demonstrated the effectiveness of the proposed robot–patient registration. ConclusionsThe proposed method enable to estimate the three-dimensional relationship between fractured bones in real-world by using only two-dimensional images, and the relationship is accurately simulated in virtual reality for the navigation. Therefore, a reduction procedure for successful treatment of bone fractures in image-guided robotic surgery can be expected with the aid of the proposed registration method.

Effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens

BackgroundTo investigate the effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens (ICL V4c).MethodsThis observational study recruited 62 eyes of 31 myopia patients underwent ICL V4c implantation. Anterior segment optical coherence tomography (AS-OCT) assessed the anterior chamber depth (ACD), ACD-ICL (distance from the corneal endothelium to anterior surface of the ICL V4c), vault (distance between the posterior ICL V4c surface and anterior crystalline lens surface), and crystalline lens tilt under various lighting conditions and accommodation relative to the corneal topographic axis at one year after ICL V4c implantation. Baseline was defined as the scotopic condition, which was also the non-accommodative stimulus condition. The ICL V4c tilt was analyzed using MATLAB. The significance level was set at P < 0.05.ResultsThe ACD-ICL values were similar under various lighting conditions (P = 0.978) but decreased during accommodation (P < 0.001). The vault was significantly smaller under mesopic and photopic conditions than the baseline (P = 0.044 and P < 0.001, respectively) but remained unchanged during accommodation (P = 0.058). The inferotemporal proportion of ICL V4c (88.7%, 55 eyes) and crystalline lens (74.2%, 46 eyes) tilts were not significantly different (P = 0.063). Crystalline lens under various lighting conditions and accommodation exhibited similar tilts. The vertical tilt of ICL V4c was significantly larger under photopic conditions than the baseline (P = 0.038). The horizontal and total tilts were significantly decreased during accommodation (P = 0.043 and 0.013, respectively).ConclusionsThe axial position of ICL V4c in the anterior chamber was stable under various lighting conditions. Lighting conditions and accommodation may influence vertical, horizontal and total tilts of ICL V4c.

3D indoor positioning with spatial modulation for visible light communications

In this paper, a novel three-dimensional (3D) indoor visible light positioning (VLP) algorithm is proposed based on the spatial modulation (SM) and its error performance assessed as compared to the conventional received signal strength (RSS)-based 3D VLP systems. As contrasted to the traditional VLP system, the proposed SM-based 3D VLP system first estimates the optical channel gain between the transmitting light-emitting diodes (LEDs) and the two photo detectors (PDs) attached to the user by a pilot-based channel estimation technique. Then, unknown 3D positions of the receiver are determined by the trilateration algorithm with distances computed from the estimates of the channel gains. Consequently, the 3D VLP system achieves an interference-free transmission with increased spectral efficiency and without the need for a demultiplexing process at the receiving end. The algorithm’s performance is evaluated regarding positioning error by applying the SM over four LEDs and the number of pilots selected as a function of the environmental signal-to-noise ratios (SNRs). The computer simulation results show that the positioning errors are obtained in an order of magnitude smaller than RSS-based techniques in an indoor industrial environment. This is mainly because the distances involved in determining the 3D positions can be determined more precisely by the pilot-aided channel estimation method without creating any data rate problem in transmission due to the higher spectral efficiency of the SM.

A one-time sampling method for the real-time measurement of bunch-by-bunch three-dimensional positions in storage rings

Bunch-by-bunch (BbB) technique, which allows accelerator physicists to monitor beam information on finer timescales, is an efficient tool for studying longitudinal and transverse beam dynamics. However, the real-time measurement in BbB technique can only monitor one beam parameter, thus focusing only on the longitudinal phase or transverse positions of bunches. Therefore, to solve this issue, we put forward a one-time sampling method (OSM) to evaluate the longitudinal phase and transverse positions of bunches simultaneously, taking as one way of the real-time measurement for BbB three-dimensional (3D) positions. And we carried out related experiments in Hefei Light Source II and Shanghai Synchrotron Radiation Facility. As a result, experiments show that OSM obtains 12 μm of x-direction resolution, 10 μm of y-direction resolution, 0.57 ps of z-direction resolution at Hefei Light Source II, and 10 μm of x-direction resolution, 10 μm of y-direction resolution, 0.35 ps of z-direction resolution at Shanghai Synchrotron Radiation Facility. All these experimental results reveal that OSM is feasible to measure the BbB 3D positions.