Development: Server Vehicle Rendezvous

Transcription

1 United States Out-of-Water Test Methods to Accelerate Implementation of Autonomous Rendezvous in the NPS ARIES AUV CAPT J.W. Nicholson, Ph.D. United States

2 Development: Server Vehicle Rendezvous Target, 1 m/s Pursuit, 1.2 m/s Prop Nav, 1.2 m/s Direct, 1 m/s Meters North Chaser Initial Position Target Initial Position Meters East

3 Challenges (As Always) Significant software changes requiring Significant debugging Limited time, money, in-water opportunities

4 ARIES Software Modifications ARIES Main Control Loop (8 Hz) Execution Process (RExec) Finite State Machine - Monitor/initiate comms - Mission sequencing - Initiate planning - Initiate replanning - Initiate activation Queue Manager Function Rdvz Queue Mission Activation Function Active Mission RExec Shared Memory Modem Shared Memory Proxy Trigger Planning Shared Memory Rdvz Mission File (RdvzTrack.out) Loiter Mission File (Track.out) Modem Process (Rfm) Acoustic Modem Mission Planning Process (RPlan) Target Target Mission Target Mission Target Data Mission Data Mission Data Data Existing functions Terminate Mission File (TerminateTrack.out)

5 ARIES State Machine Rdvz comms complete (CC) Loiter Track.out Rdvz in queue Mission infeasible Plan Msn Mission feasible New target posit / GPS fix / Replanning timeout Closing RdvzTrack.out Arrival Init Rdvz Comms Start Timeout Comms Start (CS) Rdvz Query Posit Timeout New target posit Query Posit Mission timeout Terminate TerminateTrack.out

6 ARIES Control Architecture STATE MACHINE (Strategic Level) MISSION CONTROL (Tactical Level) AUTOPILOTS (Execution Level)

7 Solution: Laboratory Test Program Hardware-in-loop software development / debugging Install the capability to run missions in laboratory (dry) Benefits Time efficient Cheap Enhanced ability to monitor vehicle operation Shortened run-debug cycle Barriers Vehicle protective functions (abort signals: prop speed, minimum altitude) Risk of equipment damage, inadvertent loss of protective functions Providing simulated sensor inputs

8 Overcoming the Barriers to Lab Testing Control all modifications with a common, reliably set and cleared signal Block unnecessary protective signals Reduce prop speed by factor of 10 Inject simulated X-Y position and GPS reception data

9 Original ARIES Software Architecture FreeWave Login Mission Script File Exec 8 Hz Exec Rec SM Modified zone Exec SM fm SM QNXE QeR 16 Hz Way Point File QNXT 10Base2 Ethernet Connection fm (Acoustic Modem) Asynch. QtS 16 Hz Nav 8 Hz Nav SM Bob II (Video Overlay) 1 Hz Indicates Direction of Data Flow BOB SM RDI SM Mot Pak SM GPS SM Analog SM HMR SM RDI (Vel / Alt) ~2 Hz MotPak (IMU) 8 Hz GPS 1 Hz Analog (Depth, etc) 8 Hz HMR (Compass) ~7 Hz

10 Initial (Stand-alone) Software Testing Acoustic modem Minor modification of existing software and shared memory Test on ARIES using actual modem software / hardware / inputs State machine and queue manager function Logic intensive operations, but little math Exhaustive testing of inputs versus states Embed into existing function (Exec.c) PC (MATLAB), translate into C on ARIES Mission planning module Math / optimization / shared memory intensive Could develop on PC, but translation to C and integration in ARIES would involve a second round of significant debugging ARIES (C)

11 Integrated Software Testing Set-up Target Track and Way Points 6 7 Meters North ARIES Loiter For In-Water Runs Start Point for Laboratory Runs Meters East

12 Time-Optimal In-Lab Track Meters North Rendezvous Point (900,500.9) Programming ARIES rendezvous behavior Target Position at Request (900,664) Start Final Course / Speed Change (881.5,515.1) Finite state machine representation of rendezvous process End of Initial Course / Speed Change (703.3, 501.5) ARIES Initial Position (690,500) Meters East

13 Replanned Time-Optimal Track Final Rendezvous Point (900.0, 490.3) Original Rendezvous Point (900.0,500.9) 4 Meters North Start Final Course / Speed Change (881.8,504.8) Programming ARIES rendezvous behavior ARIES Expected Position (759.1, 505.7) ARIES GPS Position (750,500) Meters East

14 First In-water Run: Time-optimal Rendezvous Target Position at Request 1 2 Rendezvous 0 3 Target Track Programming ARIES Replan rendezvous behavior Finite state machine representation of rendezvous process Closing Return to Loiter ARIES Loiter

15 Summary Significant savings in time / effort / money Several hundred runs, in days (vice months) Enhanced fault diagnosis, rapid correction Simulated sensor inputs need not be complete set, or high fidelity (judgment / trade-offs) Care in blocking / restoring / retesting abort and other protective functions Power down unnecessary vehicle components to avoid wear and tear (nav / comms equipment) Nominal performance first time in the water

16 Questions CAPT Jack Nicholson, USN United States

17 Back-up Slides

18 RENDEZVOUS SHARED MEMORY RExec Shared Memory Rfm Shared Memory Outgoing Message Flag Outgoing Message ARIES X Coordinate ARIES Y Coordinate ARIES Course Read by Rfm Read by RExec New Data Flag Message Command Target Number Way Point Progress ARIES Speed Time Stamp Set Drift Optimization Objective/Check Sum Current Target Number Current Way Point Current Progress Current Time Stamp Current Optimization Objective/Check Sum Clock Time Read by RPlan Read by RExec RPlan Shared Memory Proxy ID Plan Ready Flag Plan Feasible Flag

19 Target Vehicle RENDEZVOUS TRAJECTORY Rendezvous Point (X 3,Y 3 ) (X 2,Y 2 ) GPS Fix Final Course/Speed Change (X 1,Y 1 ) (X i,y i ) Initial Course/Speed Change ARIES

20 ADVANCE, TRANSFER AND PATH LENGTH Start Turn Advance Transfer Parameterization of turn characteristics 50 Turn Complete Advance Transfer Path Length 30 Meters 25 Used to compute spatial and temporal turn effects Course Change (Radians)

21 SET OF REACHABLE STATES t=t 1 Target Vehicle Initial Position t=t 2 Earliest Possible Rendezvous Target Track Chaser Vehicle Set of Reachable Positions t=t 1 Chaser Vehicle Set of Reachable Positions t=t 2 Chaser Vehicle Initial Position

22 TIME-OPTIMAL RENDEZVOUS POINT Target Vehicle Find (X 3,Y 3 ) such that distance = u max x(t 2 -t 1 ) (X 1,Y 1,t 1 ) (X i,y i ) (X 2,Y 2, t 2 ) Initial Course/Speed Change ARIES Rendezvous Point (X 3,Y 3 ) Final Course/Speed Change

23 ENERGY-OPTIMAL RENDEZVOUS POINT Target Vehicle Refine u such that distance = u(t 2 -t 1 ) (X 1,Y 1,t 1 ) (X 2,Y 2, t 2 ) Sampled Rendezvous Points (X 3,Y 3 ) Minimum Energy Rendezvous Point (X i,y i ) ARIES

24 IN-LAB RUNS Rendezvous request: RVS,REQ,0,5,120,30,+/-155

25 ENERGY-OPTIMAL IN-LAB TRACK Candidate Rendezvous Points 5 Target Position at Request (900,664) Rendezvous Point (900,420) Meters North 800 Target Target Way Point ARIES ARIES Initial Position (690,500) Meters East

26 ENERGY-OPTIMAL CALCULATIONS 9 x Energy (Joules) Candidate Rendezvous Y Coordinate

27 CONTROLS AND STATES 2 Rendezvous Request Rendezvous Heading (deg) Rudder (deg) u (m/s) u com (m/s) Programming ARIES rendezvous behavior Finite state machine representation of rendezvous process Time (sec)

28 ENERGY-OPTIMAL IN-WATER TRACK Programming ARIES rendezvous 9 behavior Replan Target Track Target Position at Request 6 7 Finite state machine representation of rendezvous process 8 Candidate Rendezvous Points Closing ARIES Loiter

29 WORK TO BE DONE MAGNETIC SWITCH PANEL DEPTH CELL TRANSDUCER BOW SECTION LEAK DETECTOR VIDEO CAMERA RDI DOPPLER SONAR BENTHOS ACOUSTIC MODEM DIGITAL VIDEO RECORDER HONEYWELL HMR3000 COMPASS MODULE SYSTRON-DONNER MOTION PAK IMU FORWARD BALLAST TANK DUAL QNX PENTIUM COMPUTERS + CONTROL BOARDS + HARD DRIVES +DC/DC POWER SUPPLIES AFT BALLAST TANK CISCO WIRELESS LAN/AMPLIFIER ASHTEC GPS RECEIVER STERN SECTION LEAK DETECTOR WIRELESS LAN ANTENNA DC/DC POWER SUPPLIES 2 TECHNADYNE MODEL 520 THRUSTERS) KEARFOTT RATE GYRO BENTHOS MODEM ELECTRONICS BOB II VIDEO CARD PC104 SENSOR PROCESSOR 12 VOLT BATTERY (6) MID SECTION LEAK DETECTOR DC/DC POWER SUPPLIES MAIN POWER RELAY CURRENT SENSOR MULTI-PURPOSE ANTENNA FREEWAVE RADIO VEHICLE TO SHORE COMM. LINK FREEWAVE RADIO DGPS LINK GPS ANTENNA FIN SERVO (6) THRUSTER CONTROL BOARD Configuration: May 2004