Autonomous Vehicle GNC

Transcription

1 Autonomous Vehicle Global issues for autonomous vehicles (Mikel - 20 min) ION Robotic Lawn Mower (Jade 40 min) Miami University s Approach A Global (Carrie and Casey 1 hour) at de Universite de Cocody (30 min) 1

2 ION Robotic Lawn Mower: Miami RedBlade 2

3 Competition Rule Evolution Known object 10 m 15 m Safety zone Unknown object 3

4 Red Blade Design Components Position Velocity Heading Sensors Obstacles Safety Emergency System Control Controller Control Algorithms Path Planning Obstacle avoidance Base Mower Actuators Mechanical Platform Remote Monitoring Simulator Position Velocity Heading Sensors Control Controller Control Algorithms Path Planning Obstacle avoidance Obstacles Base Mower Actuators Mechanical Platform 4

5 RedBlade I: Hardware Garmin GPS16 2 * $145 Hall Sensor $40 HRM3200 Compass $350 (Donation) PH Servos $1200 (Donation) Freewave Modem $3000 (Donation) Snapper Mower $5000 (Donation) 5

6 RedBlade I: Custom DGPS Mask Angle 0 Degrees West (x 0, y 0, z 0 ) Lcosθ θ L (x s, y s, z s ) ΔN: Integer carrier cycle difference East 6

7 RedBlade I: Custom DGPS Carrier phase measurement: φ = r I + T si Single difference: sj Δφ = φ φ r 0 r m (t 0 ) y r m (t) m Double difference: Δφ = Δφ si + c s ( δt δt ) + Nλ + ε u = Δr + cδt + ΔNλ + ε 0 mo m0 Δφ sj = Δr + ΔNλ + ε Measurements (x,y) Initialization Δr(t) m0 Δr(t 0 ) (x,y) Solution: 2cm accuracy x 7

8 Control Architecture PC Path Planning PID Control Path Execution Communication Drivers RTK Mower Compass Servos Magnets GPS 8

9 Control Algorithm Path n Endpoint Path n Segment 2 Endpoint Path n Segment 1 Endpoint Current Mower Location n2 n1 Path n+1 Endpoint Mower driving to path n endpoint. Path n length =10 m Breaks path n into 2 segments: n1, n2 Given current GPS location, drive 5 meter North, stop, Take new GPS reading and continues to n2 goal goal. 9

10 PID Control Generate Desired Distance Hall Sensor DGPS inputs Mower Heading - d dt Kp Ki Kd Kp + Motor Controller Setting Desired Mower Heading - d dt Ki Kd + 10

11 RedBlade II: Platform Re-design New base design Hybrid battery/gas power generation system Multi-layered shelves Electric motors 11

12 RedBlade II: Platform Re-design New base design 12

13 RedBlade II: New Electronics 2 on-board NovAtel Superstar II RX: mower heading Optical encoder Roboteq motor controller Systronix Saje Processor Programmed in Java Multi-threaded execution, dynamic class loader 13

14 RedBlade III: Obstacle Avoidance Sonar (Parallax) Scanning Laser (Sick) Stereo Vision (Unibrain) Range < 3m Over a range of 12m, the ranging error <5%. 14

15 RedBlade III: Dynamic Path Planning 15

16 RedBlade III: An Example Path Layout 16

17 Final Two Days We left campus in this shape. Mechanical support problem Laser problem IMU problem. Two days later. 17

18 RedBlade IV: Everything All Over Again New Platform 18

19 RedBlade IV: New Gadgets Topcon Hiper Lite+ IMU Edge Trimmer 19

20 RedBlade IV: Control Simulator Obastable Mower Variables: Field layout Obstacle control Sensor error model Sensor update rates Mower response time 20

21 It is raining, lightening, and thundering, but we are not ready yet. 21

22 Sample Designs from Competition Florida State CWRU Cedarville Ohio University University Evansville University of Waterloo Wright State University École de technologie supérieure 22