Despite its popularity, the development of an embedded real-time multisensor kinematic positioning and navigation system discourages many researchers and developers due to its complicated hardware environment setup and time consuming device driver development. To address these issues, this paper proposed a multisensor kinematic positioning and navigation system built on Linux with Real Time Application Interface (RTAI), which can be constructed in a fast and economical manner upon popular hardware platforms. The authors designed, developed, evaluated and validated the application of Linux/RTAI in the proposed system for the integration of the low cost MEMS IMU and OEM GPS sensors. The developed system with Linux/RTAI as the core of a direct geo-referencing system provides not only an excellent hard real-time performance but also the conveniences for sensor hardware integration and real-time software development. A software framework is proposed in this paper for a universal kinematic positioning and navigation system with loosely-coupled integration architecture. In addition, general strategies of sensor time synchronization in a multisensor system are also discussed. The success of the loosely-coupled GPS-aided inertial navigation Kalman filter is represented via post-processed solutions from road tests.
References
[1]
De Agostino, M.; Porporato, C. Development of an Italian low cost GNSS/INS system universally suitable for mobile mapping. In Proceedings of Position, Location and Navigation Symposium, 2008 IEEE/ION, Monterey, CA, USA, 5–8 May 2008; Volume 5, pp. 53–59.
Shin, E.H. Accuracy Improvement of Low-Cost INS/GPS for Land Application. M.Sc. Thesis, Geomatics Engineering Department, University of Calgary, Calgary, AB, Canada, December 2001.
[4]
Hide, C.; Moore, T.; Smith, M. Adaptive Kalman filtering algorithms for integrating GPS and low-cost INS. In Proceedings of 2004 IEEE/ION, Position, Location and Navigation Symposium, Monterey, CA, USA, 26–29 April 2004; Volume 4, pp. 227–233.
[5]
Hasan, A.M.; Samsudin, K.; Ramli, A; Azmir, R; Ismaeel, S. A review of navigation system (integration and algorithm). Aust. J. Basic Appl. Sci. 2009, 3, 943–959.
[6]
Flenniken, W.S. IV., Modeling Inertial Measurement Units and Analyzing the Effect of their Errors in Navigation Applications. M.Sc. Thesis, Auburn University, AL, USA, 16 December 2005.
[7]
Demoz, G.-E. Design and Performance Analysis of a Low-Cost Aided Dead Reckoning Navigator. Ph.D. Dissertation, Stanford University, Stanford, CA, USA, February 2004.
[8]
Park, M.; Gao, Y. Error Analysis of Low-Cost MEMS based accelerometers for land vehicle navigation. In ION GPS-2002; Portland, UT, USA, 2002.
[9]
El-Sheimy, N. Emerging MEMS IMU and Its Impact on Mapping Applications. Available online: http://www.ifp.uni-stuttgart.de/publications/phowo09/220El-Sheimy.pdf (accessed on 18 September 2012).
[10]
Marchand, A.; Plot, C.; Silly, M. Real-time mobile robot navigation with LINUX/RTAI. In Proceedings of The 2002 International Conference on Control and Automation, XiaMen, Fujian, China, 16–19 June 2002; Volume 6, p. 195.
[11]
Chen, Y.; Sun, K.; Wang, T.; Wei, H. Development and implementation of a real time embedded control system for machine tools. In Proceedings of the 2nd IEEE/ASME International Conference, Beijing, China, September 2006; Volume 8, pp. 1–5.
[12]
Barbalace, A.; Luchetta, A.; Manduchi, G.; Moro, M.; Soppelsa, A.; Taliercio, C. Performance comparison of VxWorks, Linux, RTAI, and Xenomai in a hard real-time application. IEEE Trans. Nucl. Sci. 2008, 55, 435–439, doi:10.1109/TNS.2007.905231.
[13]
Jones, M.T. Anatomy of Real-Time Linux Architectures from Soft to Hard Real-Time; IBM, 15 April 2008. 15 April 2008. Available online: http://download.boulder.ibm.com/ibmdl/pub/software/dw/linux/l-real-time-linux/l-real-time-linux-pdf.pdf (accessed on 25 May 2012).
[14]
Barabanov, M. A Linux Based Real-Time Operating System. M.Sc. Thesis, New Mexico Institute of Mining and Technology, Socorro, NM, USA, 1 June 1997.
[15]
Patrick Mourot (Alcatel, France). RTAI Internals Presentation. Available online: http://www.aero.polimi.it/~rtai/documentation/articles/patric_mourot_rtai_internal_presentation.html (accessed on 10 October 2011).
[16]
Aeolean Inc. Introduction to Linux for Real-Time Control. Available online: http://www.aeolean.com/html/RealTimeLinux/RealTimeLinuxReport-2.0.0.pdf (accessed on 15 January 2012).
[17]
RTAI API Documentation. Available online: https://www.rtai.org/documentation/magma/html/api/ (accessed on 1 September 2011).
[18]
Soetens, P. How to port your C++ GNU/Linux application to RTAI/LXRT. Available online: http://www.isr.uc.pt/~rui/str/rtai_porting.pdf (accessed on 27 February 2012).
[19]
Woodman, O.J. An Introduction to Inertial Navigation; Technical Report UCAM-CL-TR-696; University of Cambridge: Cambridge, UK, 2007.
[20]
Reis, J.; Sanguino, J.; Rodrigues, A. Impact of satellite coverage in single-frequency precise heading determination. In Proceedings of IEEE/ION PLANS 2010, Indian Wells, CA, USA, 4–6 May 2010; Volume 5, pp. 592–597.
[21]
NovAtel Inc. OEM4 Family User Manual, Volume 2, Command and Log Reference, Available online: http://www.novatel.com./Documents/Manuals/om-20000047.pdf (accessed on 15 January 2012).
[22]
Ding, W.; Wang, J.; Li, Y.; Mumford, P.; Rizos, C. Time synchronization error and calibration in integrated GPS/IMU (MEMS) systems. ETRI J. 2008, 30, 59–67, doi:10.4218/etrij.08.0106.0306.
[23]
Crossbow Technology, Inc. 440 Series User’s Manual; Document 7430-0131-01, Available online: http://www.moog-crossbow.com/_Assets/Literature/User_Manuals/440_Series_Inertial_Manual.pdf (accessed on 11 October 2011).
[24]
Crossbow Technology, Inc. DMU User’s Manual; Document 7430-0003-01, Rev A; Crossbow Technology, Inc.: San Jose, CA, USA, 2002.
[25]
Li, B. A cost effective synchronization system for multisensor integration. In Proceedings of the 17th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GNSS 2004), Long Beach, CA, USA, September 2004; Volume 9, pp. 1627–1635.
[26]
Lee, H.; Lee, J.; Jee, G. Calibration of time synchronization error in GPS/SDINS hybrid navigation. In Proceedings of the 15th IFAC Symposium on Automatic Control in Aerospace, Bologna/Forli, Italy, 2–7 September 2001; Volume 9, pp. 223–228.
[27]
Skog, I.; Handel, P. Time synchronization errors in loosely coupled GPS-aided inertial navigation system. IEEE Trans. Intel. Transp. Syst. 2011, 12, 1014–1023, doi:10.1109/TITS.2011.2126569.