Augmented Marker Tracking for Peri-acetabular Osteotomy Surgery: A Cadaver Study

Purpose. To validate a small, easy to use and cost-effective augmented marker-based hybrid navigation system for peri-acetabular osteotomy surgery.Methods. A cadaver study including 3 pelvises (6 hip joints) undergoing navigated PAO was performed. Inclination and anteversion of two navigation systems for PAO were compared during acetabular reorientation. The hybrid system consists of a tracking unit which is placed on the patient’s pelvis and an augmented marker which is attached to the patient’s acetabular fragment. The tracking unit sends a video stream of the augmented marker to the host computer. Simultaneously, the augmented marker sends orientation output from an integrated inertial measurement unit (IMU) to the host computer. The host computer then computes the pose of the augmented marker and uses it (if visible) to compute acetabular orientation. If the marker is not visible, the output from the IMU is used to update the orientation. The second system served as ground truth and is a previously developed and validated optical tracking-based navigation system.Results. Mean absolute difference for inclination and anteversion (N = 360) was 1.34 degrees and 1.21 degrees, respectively. The measurements from our system show a very strong correlation to the ground-truth optical tracking-based navigation system for both inclination and anteversion (0.9809 / 0.9711).Conclusion. In this work we successfully demonstrated the feasibility of our system to measure inclination and anteversion during acetabular reorientation.

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An Improved and Efficient Algorithm for SINS/GPS/Doppler Integrated Navigation Systems

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.245.323 ◽

2012 ◽

Vol 245 ◽

pp. 323-329 ◽

Cited By ~ 4

Author(s):

Muhammad Ushaq ◽

Jian Cheng Fang

Keyword(s):

Kalman Filter ◽

Navigation System ◽

Inertial Navigation System ◽

Inertial Sensor ◽

Inertial Navigation ◽

Measurement Unit ◽

Navigation Systems ◽

Integrated Navigation ◽

Efficient Manner ◽

Position Errors

Inertial navigation systems exhibit position errors that tend to grow with time in an unbounded mode. This degradation is due, in part, to errors in the initialization of the inertial measurement unit and inertial sensor imperfections such as accelerometer biases and gyroscope drifts. Mitigation to this growth and bounding the errors is to update the inertial navigation system periodically with external position (and/or velocity, attitude) fixes. The synergistic effect is obtained through external measurements updating the inertial navigation system using Kalman filter algorithm. It is a natural requirement that the inertial data and data from the external aids be combined in an optimal and efficient manner. In this paper an efficient method for integration of Strapdown Inertia Navigation System (SINS), Global Positioning System (GPS) and Doppler radar is presented using a centralized linear Kalman filter by treating vector measurements with uncorrelated errors as scalars. Two main advantages have been obtained with this improved scheme. First is the reduced computation time as the number of arithmetic computation required for processing a vector as successive scalar measurements is significantly less than the corresponding number of operations for vector measurement processing. Second advantage is the improved numerical accuracy as avoiding matrix inversion in the implementation of covariance equations improves the robustness of the covariance computations against round off errors.

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Improving registration accuracy during total hip arthroplasty: a cadaver study of a new, 3-D mini-optical navigation system

Hip International ◽

10.5301/hipint.5000533 ◽

2017 ◽

Vol 28 (1) ◽

pp. 33-39 ◽

Cited By ~ 7

Author(s):

Michael B. Cross ◽

Ran Schwarzkopf ◽

Theodore T. Miller ◽

Eric A. Bogner ◽

Jeffrey M. Muir ◽

...

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Navigation System ◽

Cadaver Study ◽

Mean Difference ◽

Reference Plane ◽

Absolute Difference ◽

Registration Error ◽

Total Hip ◽

The Mean

Introduction: Maintaining accuracy of component placement is an important step in ensuring the long-term stability of components during total hip arthroplasty (THA). Computer-assisted navigation has improved accuracy but errors associated with the registration process are known to impact the accuracy of final measurements. The purpose of this cadaver study was to determine the registration error associated with a novel mini-navigation system. Methods: 3 board-certified orthopaedic surgeons performed 4 THA procedures each via the posterolateral approach on 6 cadavers (12 hips) using the mini-navigation tool. Pre- and post-operative radiographs and post-operative computed tomography (CT) images were obtained. Image analysis was performed by 2 radiologists not involved in the surgical procedures. During registration, surgeons aligned the alignment rod with the anterior pelvic plane (APP) to provide a reference plane for comparison with traditional navigation. Cup position from the device was compared with measurements gathered from post-op imaging. Results: The mean difference between CT and device measurements for inclination was -1.7° (standard deviation [SD] 4.9°), while the mean absolute difference was 4.2° (SD 3.2°). The mean difference between anteversion angles calculated from CT scans and from the device was -3.5° (SD 4.5°), with an absolute difference of 4.0° (SD 4.0°). 100% (12/12) of inclination measurements and 92% (11/12) of anteversion measurements fell within both the clinical and statistical limits of agreement when analyzed via the Bland-Altman technique. Conclusions: This study demonstrates that the registration error associated with this new mini-navigation system compares favourably with the known registration error associated with traditional navigation systems.

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Multiple Model Adaptive Rank Estimation for Integrated Navigation During Mars Entry

Journal of Navigation ◽

10.1017/s037346331600059x ◽

2016 ◽

Vol 70 (2) ◽

pp. 291-308 ◽

Cited By ~ 2

Author(s):

Qiang Xiao ◽

Huimin Fu ◽

Zhihua Wang ◽

Yongbo Zhang

Keyword(s):

Navigation System ◽

Uncertain System ◽

Measurement Unit ◽

Filter Method ◽

Navigation Systems ◽

Integrated Navigation ◽

Multiple Model ◽

Integrated Navigation System ◽

Rank Estimation ◽

Three Degree Of Freedom

Accurate navigation systems are required for future pinpoint Mars landing missions. A radio ranging augmented Inertial Measurement Unit (IMU) integrated navigation system concept is considered for the Mars entry navigation. The uncertain system parameters associated with the Three Degree-Of-Freedom (3-DOF) dynamic model, and the measurement systematic errors are considered. In order to improve entry navigation accuracy, this paper presents the Multiple Model Adaptive Rank Estimation (MMARE) filter of radio beacons/IMU integrated navigation system. 3-DOF simulation results show that the performances of the proposed navigation filter method, 70·39 m estimated altitude error and 15·74 m/s estimated velocity error, fulfill the need of future pinpoint Mars landing missions.

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Enhanced Accuracy Navigation Solutions Realized through SINS/GPS Integrated Navigation System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.332.79 ◽

2013 ◽

Vol 332 ◽

pp. 79-85

Author(s):

Outamazirt Fariz ◽

Muhammad Ushaq ◽

Yan Lin ◽

Fu Li

Keyword(s):

Kalman Filter ◽

Navigation System ◽

Inertial Navigation System ◽

Inertial Sensor ◽

Inertial Navigation ◽

Measurement Unit ◽

Navigation Systems ◽

Integrated Navigation ◽

Position Errors ◽

Strapdown Inertial Navigation

Strapdown Inertial Navigation Systems (SINS) displays position errors which grow with time in an unbounded manner. This degradation is due to the errors in the initialization of the inertial measurement unit, and inertial sensor imperfections such as accelerometer biases and gyroscope drifts. Improvement to this unbounded growth in errors can be made by updating the inertial navigation system solutions periodically with external position fixes, velocity fixes, attitude fixes or any combination of these fixes. The increased accuracy is obtained through external measurements updating inertial navigation system using Kalman filter algorithm. It is the basic requirement that the inertial data and data from the external aids be combined in an optimal and efficient manner. In this paper an efficient method for integration of Strapdown Inertial Navigation System (SINS), Global Positioning System (GPS) is presented using a centralized linear Kalman filter.

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A Low-Cost Method of Improving the GNSS/SINS Integrated Navigation System Using Multiple Receivers

Electronics ◽

10.3390/electronics9071079 ◽

2020 ◽

Vol 9 (7) ◽

pp. 1079 ◽

Cited By ~ 2

Author(s):

Di Liu ◽

Hengjun Wang ◽

Qingyuan Xia ◽

Changhui Jiang

Keyword(s):

Navigation System ◽

Low Cost ◽

Field Tests ◽

Measurement Unit ◽

Filter Method ◽

Navigation Systems ◽

Integrated Navigation ◽

Integration System ◽

Integrated Navigation System ◽

Multiple Receivers

GNSS (global navigation satellite system) and SINS (strap-down inertial navigation system) integrated navigation systems have been the apparatus for providing reliable and stable position and velocity information (PV). Commonly, there are two solutions to improve the GNSS/SINS integration navigation system accuracy, i.e., employing GNSS with higher position accuracy in the integration system or utilizing the high-grade inertial measurement unit (IMU) to construct the integration system. However, technologies such as RTK (real-time kinematic) and PPP (precise point positioning) that improve GNSS positioning accuracy have higher costs and they cannot work under high dynamic environments. Also, an IMU with high accuracy will lead to a higher cost and larger volume, therefore, a low-cost method to enhance the GNSS/SINS integration accuracy is of great significance. In this paper, multiple receivers based on the GNSS/SINS integrated navigation system are proposed with the aim of providing more precise PV information. Since the chip-scale receivers are cheap, the deployment of multiple receivers in the GNSS/SINS integration will not significantly increase the cost. In addition, two different filtering methods with central and cascaded structure are employed to process the multiple receivers and SINS integration. In the centralized integration filter method, measurements from multiple receivers are directly processed to estimate the SINS errors state vectors. However, the computation load increases heavily due to the rising dimension of the measurement vector. Therefore, a cascaded integration filter structure is also employed to distribute the processing of the multiple receiver and SINS integration. In the cascaded processing method, each receiver is regarded as an individual “sensor”, and a standard federated Kalman filter (FKF) is implemented to obtain an optimal estimation of the navigation solutions. In this paper, a simulation and a field tests are carried out to assess the influence of the number of receivers on the PV accuracy. A detailed analysis of these position and velocity results is presented and the improvements in the PV accuracy demonstrate the effectiveness of the proposed method.

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A Multimodality Navigation System for Endoscopic Fetal Surgery: A Phantom Case Study for Congenital Diaphragmatic Hernia

Surgical Innovation ◽

10.1177/1553350618813244 ◽

2018 ◽

Vol 26 (1) ◽

pp. 27-36 ◽

Cited By ~ 1

Author(s):

Hariprashanth Elangovan ◽

Wei Yao ◽

Kypros Nicolaides

Keyword(s):

Congenital Diaphragmatic Hernia ◽

Diaphragmatic Hernia ◽

Navigation System ◽

Fetal Surgery ◽

Optical Tracking ◽

Navigation Systems ◽

Surgical Equipment ◽

Extensive Experience ◽

Robotic Instruments ◽

Navigation Software

This article presents a multi-modality tracking and navigation system achieved by merging optical tracking and ultrasound imaging into a novel navigation software to help in surgical pre-planning and real-time target setting and guidance. Fetal surgeries require extensive experience in coordination of hand-eye-ultrasound-surgical equipment, knowledge, and precise assessment of relative anatomy. While there are navigation systems available for similar constrained working spaces in arthroscopic and cardiovascular procedures, fetal minimally invasive surgery does not yet have a dedicated navigation platform capable of supporting robotic instruments that can be adapted to the set of unique procedures. This article discusses the testing of the novel multi-modality navigation system in a phantom environment developed for this purpose. The outcomes suggest that the subjects demonstrated an increase in average reaching accuracy by about 60% and an overall reduction in time taken by 33.6%. They also showed higher levels of confidence in reaching the targets, which was visualised from the pattern of trajectory of movements during the procedure. To evaluate the navigation system, a phantom surgical environment was found necessary. Therefore, the article also discusses the details of the development of a fetal phantom environment for congenital diaphragmatic hernia for surgical testing, evaluation, and training. A surgical procedure was conducted on the phantom using the proposed tracking navigation system and using only ultrasound.

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A Parameter Self-Calibration Method for GNSS/INS Deeply Coupled Navigation Systems in Highly Dynamic Environments

Sensors ◽

10.3390/s18072341 ◽

2018 ◽

Vol 18 (7) ◽

pp. 2341

Author(s):

Zang Chen ◽

Jizhou Lai ◽

Jianye Liu ◽

Rongbing Li ◽

Guotian Ji

Keyword(s):

Navigation System ◽

Tracking Error ◽

Coupled System ◽

Calibration Method ◽

Dynamic Environments ◽

Coupled Systems ◽

Measurement Unit ◽

Present System ◽

Navigation Systems ◽

Self Calibration

The GNSS/INS (Global Navigation Satellite System/Inertial Navigation System) navigation system has been widely discussed in recent years. Because of the unique INS-aided loop structure, the deeply coupled system performs very well in highly dynamic environments. In practice, vehicle maneuvering has a big influence on the performance of IMUs (Inertial Measurement Unit), and determining whether the selected IMUs and receiver parameters satisfy the loop dynamic requirement is still a critical problem for deeply coupled systems. Aiming at this, a new parameter self-calibration method based on the norm principle is proposed which explains the relationship between IMU precision and the velocity error of the system; the method will also provide a detailed solution to calculate the loop steady-state tracking error, so it will eventually make a judgment about the stability of the tracking loop under present system parameter settings. Lastly, a full digital simulation platform is set up, and the results of simulations show good agreement with the proposed method.

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Comparison of the accuracy of CT- and accelerometer-based navigation systems for cup orientation in total hip arthroplasty

Hip International ◽

10.1177/1120700020904940 ◽

2020 ◽

pp. 112070002090494 ◽

Cited By ~ 1

Author(s):

Tomonori Tetsunaga ◽

Kazuki Yamada ◽

Tomoko Tetsunaga ◽

Takayuki Furumatsu ◽

Tomoaki Sanki ◽

...

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Navigation System ◽

Pelvic Tilt ◽

Lateral Decubitus Position ◽

Absolute Difference ◽

Navigation Systems ◽

Total Hip ◽

Navigation Group ◽

Lateral Decubitus

Background: The accuracies of various navigation systems in total hip arthroplasty (THA) have been described; however, the accuracy of cup orientation with an accelerometer-based navigation system has not been reported. The purpose of this study was to compare the accuracies of computed tomography (CT)- and accelerometer-based navigation systems for cup orientation in THA. Methods: In this prospective study, 30 patients who underwent cementless THA via anterolateral approach in the lateral decubitus position were analysed. A CT-based navigation system (30 hips) and an accelerometer-based navigation system (30 hips) were used simultaneously. The accuracy of cup orientation (absolute difference between intraoperative vs. postoperative measurements) was compared between the navigation systems using postoperative CT. Results: The accuracy of cup inclination was 3.2 ± 2.4° in the CT-based navigation group and 4.1 ± 3.7° in the accelerometer-based navigation group ( p = 0.3035). The accuracy of cup anteversion was 3.0° ± 2.5° in the CT-based navigation group and 6.8° ± 4.8° in the accelerometer-based navigation group. Cup anteversion was significantly more accurate with the CT-based navigation system than with accelerometer-based navigation ( p = 0.0009). Multiple regression analysis demonstrated that the malposition in cup anteversion was positively correlated with the change in pelvic tilt and loosening of the reference antenna. Conclusions: Although, these results are only true for this specific accelerometer system, cup positioning was significantly more accurate with the CT-based navigation system than an accelerometer-based navigation in the lateral decubitus position. This is because of considerable discrepancies in the sagittal pelvic tilt, resulting in variability in cup anteversion angle with the use of an accelerometer-based navigation system.

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Endoscopic Augmented Reality Navigation System for Endonasal Transsphenoidal Surgery to Treat Pituitary Tumors: Technical Note

Neurosurgery ◽

10.1097/00006123-200206000-00038 ◽

2002 ◽

Vol 50 (6) ◽

pp. 1393-1397 ◽

Cited By ~ 23

Author(s):

Takakazu Kawamata ◽

Hiroshi Iseki ◽

Takao Shibasaki ◽

Tomokatsu Hori

Keyword(s):

Augmented Reality ◽

Navigation System ◽

Transsphenoidal Surgery ◽

Tracking System ◽

Three Dimensional ◽

Pituitary Tumors ◽

Optical Tracking ◽

Navigation Systems ◽

Optical Tracking System ◽

Light Emitting

Abstract OBJECTIVE Endoscopes have been commonly used in transsphenoidal surgery to treat pituitary tumors, to compensate for the narrow surgical field. Although many navigation systems have been introduced for neurosurgical procedures, there have been few reports of navigation systems for endoscopic operations. This report presents our recently developed, endoscopic, augmented reality (AR) navigation system. METHODS The technology is based on the principles of AR environment technology. The system consisted of a rigid endoscope with light-emitting diodes, an optical tracking system, and a controller. The operation of the optical tracking system was based on two sets of infrared light-emitting diodes, which measured the position and orientation of the endoscope relative to the patient's head. We used the system during endonasal transsphenoidal operations to treat pituitary tumors in 12 recent cases. RESULTS Anatomic, “real,” three-dimensional, virtual images of the tumor and nearby anatomic structures (including the internal carotid arteries, sphenoid sinuses, and optic nerves) were superimposed on real- time endoscopic live images. The system also indicated the positions and directions of the endoscope and the endoscopic beam in three-dimensional magnetic resonance imaging or computed tomographic planes. Furthermore, the colors of the wire-frame images of the tumor changed according to the distance between the tip of the endoscope and the tumor. These features were superior to those of conventional navigation systems, which are available only for operating microscopes. CONCLUSION The endoscopic AR navigation system allows surgeons to perform accurate, safe, endoscope-assisted operations to treat pituitary tumors; it is particularly useful for reoperations, in which midline landmarks may be absent. We consider the AR navigation system to be a promising tool for safe, minimally invasive, endonasal, transsphenoidal surgery to treat pituitary tumors.

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Application of Discrete Cross-Correlation Function for Observational-Comparative Navigation System

Annual of Navigation ◽

10.1515/aon-2017-0004 ◽

2017 ◽

Vol 24 (1) ◽

pp. 49-65

Author(s):

Jan Matuszewski ◽

Wojciech Grzywacz

Keyword(s):

Correlation Function ◽

Navigation System ◽

Cross Correlation ◽

Digital Camera ◽

Cross Correlation Function ◽

Computer Application ◽

Measurement Unit ◽

Navigation Systems ◽

Integrated Navigation ◽

Matlab Programming

Abstract The article presents navigation system project operating on the principle scene matching area correlation (SMAC), using a digital camera, an MEMS e-compass sensor and an ultrasonic ranging module. Systems of this type are used as a component of advanced integrated navigation systems in view of its autonomy and capability of localizing aircrafts with high accuracy and precision. Steering and display of information are implemented using a computer application designed in Matlab programming environment. The object’s location is fixed, using discrete cross-correlation function through matching of the registered terrain image to digital orthophotomap. The article describes operations directly related to digital image processing, its implementation methods, a structural system design with explanations of each of the functional elements and presents devices used to build a complete integrated measurement unit model. It was used for the effectiveness measurement of determining the location of an object depending on the changes of angle and height of the flight as well as the luminance and noise level in a registered image. The measurements methodology was described which also includes an analysis of the results, an effectiveness evaluation and potential development directions of the designed system.

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