GPS in Mobile Application
- 1. GPS - Base Station - RTKs Date: 14.09.2017 Presented by: Sonnet Xavier
- 2. OBJECTIVE AT THE END OF THIS SESSION, YOU WILL KNOW 2 Ⓒ 2017 QBurst Technologies | Confidential and Proprietary 1. GNSS 2. How does GPS work? 3. GPS errors and corrections 4. What is a base station? 5. What is an RTK? 6. GPS and construction equipments 7. Technical innovations in construction industry 8. AWARE
- 3. GNSS GLOBAL NAVIGATION SATELLITE SYSTEM 3 Ⓒ 2017 QBurst Technologies | Confidential and Proprietary
- 4. GNSS 4 What is Satellite Navigation? Ⓒ 2017 QBurst Technologies | Confidential and Proprietary ● Space Segment ● Control Segment ● User Segment ● GPS (NAVSTAR) - USA ● GLONASS - Russia ● Galileo - Europe Components: Examples: A satellite navigation or satnav system is a system that uses satellites to provide autonomous geo-spatial positioning.
- 5. GPS GLOBAL POSITIONING SYSTEM 5 Ⓒ 2017 QBurst Technologies | Confidential and Proprietary
- 6. 6 More satellites you find, More accurate your location ○ With 3 - Latitude & Longitude ○ With 4 - Altitude Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS THE MOST WIDELY USED GNSS IN THE WORLD How does GPS find you? It is not the GPS which finds you, it's you who find the GPS
- 7. 7 Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS HOW DOES GPS WORK? ● Satellite transmits signals ○ Accurate timestamps ○ Orbit details (Satellite position) ○ L1 & L2 (Carrier Signals) ● GNSS Receiver ○ Antenna ○ Processing Unit ● Antennas receive the signals from satellites and calculate the time difference. ● Distance = Time x Velocity
- 8. 8 Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS HOW DOES GPS WORK?
- 9. 9 Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS HOW DOES GPS WORK? Receiver should collect signals from at least 3 satellites so that it gets a precise position. Processing unit then translates its own position into an earth based coordinate system as ● Latitude ● Longitude ● Altitude We could pinpoint our location with ● 5 - 10 meter Typical accuracy ● Around 15 meter potential Error due to: ○ Satellite Clocks ○ Orbit Errors ○ Ionospheric Delay ○ Tropospheric Delay
- 10. 10 Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS GPS APPLICATIONS ● Ground Mapping ● Transportation ● Machine Control ● Port Automation ● Precision Agriculture ● Timing ● Construction ● Marine ● Mining ● Surveying
- 11. GPS ERRORS AND CORRECTIONS Ⓒ 2017 QBurst Technologies | Confidential and Proprietary 11
- 12. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS ERROR 12
- 13. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS ERROR IONOSPHERIC DELAY AND TROPOSPHERIC DELAY Multipath 13
- 14. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS ERROR CORRECTIONS In general the techniques to resolve the Errors can be described as: ● Averaging of repeated observations at the same location (the least efficient method). ● Modeling of the phenomenon that is causing the error and predicting the correction values. ● Differential Corrections (DGNSS). ○ RTK ○ Post-Processing 14
- 15. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS AND CONSTRUCTION FIELD ● Improves worker safety ● Reduces project delays ● Reduces fuel consumption ● Improves efficiencies at each stage of the project ● Also prevents theft or misplacement of construction equipment ● Provide real time monitoring for equipment maintenance In construction fields we require a very high level of accuracy. ● Normal - 30’ accuracy ● We would require < 1’ accuracy ● How to bring the 30ft GPS window to much smaller??????? ● Most widely used GPS Correction Methods: DGPS & RTK 15
- 16. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary ● Referred to as Differential GNSS / GPS ● GPS Error correction method ● In DGPS, two receivers are used, One receiver is located at accurately surveyed point referred to as “Base Station” ● A correction is calculated by the known location of the base station to the location determined by the GPS satellites ● The correction is then applied to the other receiver’s (referred to as “Rover”) calculated position. ● This result is much more accurate, in fact this accuracy is normally 1.5 - 15 f. ● DGPS uses Pseudo Random Code (PRC) from satellite signals to calculate the propagation delays and to calculate the underlying position. This is known as Code- based Positioning DGPS OR DGNSS 16
- 17. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary DGPS 17
- 18. BASE STATION AND ROVER Base Station Ⓒ 2017 QBurst Technologies | Confidential and Proprietary ● A base station is a GPS receiver at an accurately-known fixed location which is used to derive correction information for nearby portable GPS receivers. ● “Known position” - It has a high degree of accuracy using a surveyed location or by averaging its position over time (12-18 hours usually) Rover ● The rover is a GPS receiver is mounted on a pole, vehicle, marine vessel, or in a backpack, and is moved between the points that require measurement or Location. 18
- 19. BASE STATION AND ROVER Ⓒ 2017 QBurst Technologies | Confidential and Proprietary 19
- 20. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary RTK - REAL TIME KINEMATICS ● GPS Error Correction method ● RTK uses a similar set-up to the DGPS system (Base Station and Rovers) ● Unlike DGPS, RTK uses carrier-based ranging for its underlying position information ● The base station for the RTK setup transmits the phase of the signal that it observes and sends that information to the rovers who then compare that to the phase that they observe ● RTK gives very high level of accuracy, upto 1cm - 1ppm 20
- 21. RTK Ⓒ 2017 QBurst Technologies | Confidential and Proprietary 21
- 22. Fixed RTK Ⓒ 2017 QBurst Technologies | Confidential and Proprietary AMBIGUITY RESOLUTION RTK uses a complicated mathematical formula or algorithm to calculate the exact number of radio wavelengths between the satellites and the base station antenna and yield either a Fixed or Float solution. ● If a sufficient number of satellites are visible, RTK can provide a fixed position, within a fraction of an inch (0.01 - 0.1 f) ● In a fixed solution, the number of wavelengths is a whole number, or integer, and the algorithm is constrained to yield a whole number 22
- 23. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary AMBIGUITY RESOLUTION Float RTK In a float solution, the algorithm does not yield an acceptable fixed solution, so the ambiguity is allowed to be a decimal or floating point number ● A low number of visible satellites ● Poor satellite constellation geometry ● A poor radio link between the base station and the rover may prevent a fixed solution (< 1 f). 23
- 24. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS CORRECTION 1. Autonomous 30 - 45 ft 2. DGPS 1.5 - 15 ft 3. Float RTK < 1 ft 4. Fixed RTk 0.01 - 0.1 ft 24
- 25. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS AND CONSTRUCTION EQUIPMENT Man rovers in the field conduct topos on the site, measure stockpiles, layout the project and stake out pads, roads and other project elements 25
- 26. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS AND CONSTRUCTION EQUIPMENT On excavators, the GPS/GNSS antenna is usually mounted on near the counterweight 26
- 27. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary GPS AND CONSTRUCTION EQUIPMENT The antenna for machine rovers are typically moved on the blade and use the corrected GPS signals to guide the dozers or motor graders to the exact coordinates of the finished surface 27
- 28. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary SOLUTION PROVIDERS Trimble & Sitech (the distribution channel for Trimble products) ● SCS900 Site Controller Software ● SPS855 GNSS Modular Receiver ● SPS985 GNSS Smart Antenna 28
- 29. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary TRIMBLE - SPS985 GNSS SMART ANTENNA Features and Benefits: ● Rugged, All-in-one Solution ● Trimble xFill Technology ● Flexibility Applications: ● Wi-Fi Base Station ● Rover 29
- 30. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary CATERPILLAR DETECT FOR PERSONNEL Provide a technology to detect ground workers in an unsafe area behind the equipment. 30
- 31. TRIMBLE - SPS985 GNSS SMART ANTENNA Redpoint Ⓒ 2017 QBurst Technologies | Confidential and Proprietary ● Indoor GPS for Construction Safety ○ Using RTLS (Real Time Location System) ○ https://www.youtube.com/watch?v=Vi0WEQQmzPY Nextpoint ● NextPoint provides Construction Equipment GPS Tracking Systems for any type of small, medium or large commercial equipment or mobile asset. ● System can track every movement and event in real time. 31
- 32. AWARE WORK ZONE INTRUSIONS Ⓒ 2017 QBurst Technologies | Confidential and Proprietary 32
- 33. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary AWARE Oldcastle Materials Group along with QBurst & Artis are developing a system of sensors to help detect and prevent accidents caused by intrusions into mobile work zones nationwide. The system is called AWARE and involves a suite of devices designed to monitor traffic flow in and around mobile work zones. It was designed specifically to detect traffic incursions at the job site using GPS and provide advanced warning to all personnel, helping to prevent injury. The AWARE System has four main components:● A high tech sensor called the Raven ● A GPS-based worker alert unit called WorkTrax ● A visible and audible alert system for the traveling public (threat deterrent) ● An AWARE application that runs on an iPad or tablet. The devices and the application communicate with each other over a Digi network using BLE technology. 33
- 34. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary AWARE THIS IS OUR “WHY” The STATS: ● According to the National Highway Traffic Safety Administration (NHTSA), 80% of accidents and 60% of highway deaths are the result of distracted drivers. ● Vehicle Intrusions are the leading cause of worker fatalities with the road construction industry. In 2013, there were 67,523 crashes in work zones. In 2014, there were 669 fatalities from crashes in work zones 35
- 35. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary WHAT IS AWARE A system of sensors designed to detect work zone intrusions that includes radars, GPS sensors, motion sensors, optical sensors, and carefully tailored software. SYSTEM COMPONENTS 36 RAVEN WORKTRAX THREAT DETERRENT BASE STATION
- 36. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary Workers with WorkTrax AWARE Watch video 34
- 37. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary AWARE HOW DOES IT DETERMINE THE WORK ZONE BOUNDARIES? ● The GPS records where your machine has been ● The radar tracks where normal traffic is flowing ● Using both GPS and radar, we determine the boundary between traffic flow and active work (shown in red) 37
- 38. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary AWARE HOW DOES IT WORK? ● We track all vehicles as they approach within 600’ of the Raven ● The radar measures speed, position and trajectory. ● The system alerts drivers and workers in unsafe circumstances exist. ● 3 Basic applications 38
- 39. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary AWARE 3 BASIC APPLICATIONS Stationary Situation – Flagging Station, Maintenance Crews, Lone Worker Moving Merge – MOT (cone) Trucks, Striping Operations, Sweeping Operations, Road Rangers, School Buses Active Work Zones – Paving, Milling, or Construction Operations within (non-protected) lane closure 39
- 40. OLDCASTLE MATERIALS GROUP Ⓒ 2017 QBurst Technologies | Confidential and Proprietary 40
- 41. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary OLDCASTLE AN INDUSTRY LEADER COMMITTED TO SAFETY AND CUSTOMER SERVICE Oldcastle Materials is the leading vertically integrated supplier of aggregates, asphalt, ready-mix concrete, and construction and paving services in the United States. No. 1 Asphalt producer in North America No. 1 Asphalt paver in North America No. 2 Aggregates producer in North America No. 2 Cement producer in Canada No. 2 Ready-mix producer in North America 41
- 42. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary OLDCASTLE MATERIALS GROUP 1,500+ Locations 20,000+ Employees Product Position Asphalt RMC Aggregates No. 1 No. 3 No.3 42
- 43. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary HOW YOU KNOW US…… 43
- 44. Ⓒ 2017 QBurst Technologies | Confidential and Proprietary PART OF A BIGGER COMPANY +90,000 People 31 Countries 44
- 45. QUESTIONS ? Ⓒ 2017 QBurst Technologies | Confidential and Proprietary 45
- 46. THANK YOU Ⓒ 2017 QBurst Technologies | Confidential and Proprietary 45