GPS World, April 2016

INTEGER AMBIGUITY RESOLUTION IN MULTI EPOCH GPS INS ADVERTISER INDEX COMPANIES FEATURED IN THIS ISSUE APRIL 2016 WWW GPSWORLD COM GPS WORLD 49 UAV MULTIPLE LASER INERTIAL NAV INDOOR FLIGHT DEMONSTRATION RESULTS OF AN AUTONOMOUS MULTI COPTER USING MULTIPLE LASER INERTIAL NAVIGATION by Adam Schultz Russell Gilabert and Maarten Uijt de Haag Ohio University T his paper discusses aspects of autonomy on a smallsize multi copter UAS for challenging environments addresses in detail the modified proposed navigation algorithm its integration with the flight controller for autonomous flight and the actual implementation on the multi copter platform The paper includes flight test results of a multi copter UAS operating in an outdoor indoor environment and shows some navigation and mapping performance results Presented at ION ITM 2016 ADVERTISER PAGE S AUVSI 36 CAST NAVIGATION 5 CHC NAVIGATION 39 COMNAV TECHNOLOGY 21 GEO BUSINESS CONFERENCE 48 EUROPEAN NAVIGATION CONFERENCE 40 INSTITUTE OF NAVIGATION ION 29 41 KCS BV INSIDE BACK COVER KVH INDUSTRIES 7 ADVERTISER PAGE S MUNDOGEO 25 NOVATEL BACK COVER RACELOGIC 17 ROHDE SCHWARZ INSIDE FRONT COVER SBG SYSTEMS 15 SEPTENTRIO 13 SUZHOU FOIF CO 37 SWIFT NAVIGATION 9 35 TALLYSMAN 23 A novel integer ambiguity resolution approach over a time window of GPS IMU data enhances the reliability of obtaining high accuracy position estimation using carrier phase measurements even in challenging environments The method focuses on reducing computational cost The achievable savings should be on the order of 104 while 600 has been demonstrated The theoretical approach shows that the cost function can be decomposed into one part that determines the shape and vicinity of the trajectory but is insensitive to the carrier phase integers and a position shift vector and a second part that is sensitive to the carrier phase integer and can be solved to determine the required position shift so that the location of the trajectory is accurately known By Yiming Chen Sheng Zhao and Jay A Farrell University of California Riverside Pre sented at IEEE Transactions on Control Systems Technology 2015 illustration of the contemplative real time CRT window measurement timeline The window contains a prior for the initial state K GPS measurements and many IMU measurements between each pair of GPS measurements IMU measurement times are indicated as dots on the timeline All of these items yield constraints on the estimated trajectory ˆ X during the CRT window