1

Mission DetailsAA241x - Design, Construction, and Testing of Autonomous Aircraft

Lecture 3April 8, 2013

Juan J. AlonsoRoberto BungeWade SpurlockDepartment of Aero & AstroStanford UniversityStanford, CA 94305, U.S.A.

Personnel

• Instructor:– Prof. Juan J. Alonso, Durand 252, x3-9954,

jjalonso@stanford.edu

• Course Assistants (CAs):– Robbie Bunge (lead CA), Durand 464 / 353 /

055, rbunge@stanford.edu– Wade Spurlock, Durand 353 / 055,

wadespur@stanford.edu

2

Communications

• General announcements:– aa241x-class@lists.stanford.edu

• Course website for lecture notes, rosters, useful links, code.google.com, etc:– http://adl.stanford.edu/groups/aa241x

• All Q&A through Piazza site• Each team must have its own website by

the Due Date of PS1

3

Team Websites

• You will be required to have a team website that contains:– Team members, contact information,

responsibilities– All technical details of your design, controls,

mission planning (it is up to you how you want to organize it…but it must be kept current: we will check it regularly to gauge progress)

– Presentations / data– Pictures, videos, etc. documenting work

4

5 Teams

• Game of Drones

• Pegasus

• Planet Express

• Infinity Eye

• Chimera

5

Mission – Search & Rescue

• This year’s mission is inspired by search & rescue missions

• As every year, this is a competition: one winner. Which team will it be? There is a prize for the top 2 teams…

• “Find” and “locate” three targets (stranded people) in Lake Lagunita

• Two components for “mission score”:– Time to first “sight” all 3 targets: tsight in seconds

– Reported location of each target: (distances in meters)

• Total score, J, with a = 300 m, =2,000 b sec, g = 3 m:

6

i

Lake Lagunita – Aerial View7

Allowable area

✖

✖

✖

✖Target

Camera Field of View (FOV) = f(h)

Target position estimate, R = g(h)

Estimated location

Important Parameters• Total score, J, with a = 300 m, =2,000 b sec, g = 3 m:

• FOV:– Diameter = 100 m @ 400 ft altitude (max altitude permitted)– Diameter = 50 m @ 100 ft altitude (min altitude permitted)– Linear variation in between

• Target position estimate (TPE), R:– Diameter = 25 m @ 400 ft altitude– Diameter = 10 m @ 100 ft altitude

• Battery life is not unlimited! Target 600 mAh, 2 cell LiPo, but can vary!

8

“Camera” API• snapshot mySnapShot = takeASnapShot();

will return:– bool targetInPic[3] with True/False for each of the targets 0,

1, and 2– float targetLat[3], targetLong[3], targetRadius[3]

containing (for targetInPic[i] == True) the latitude and longitude of the center of the TPE, and its radius

• TPE has its center at the location of the actual target + noise

• Noise in center of TPE is drawn from a uniform distribution (in lat and long) between –R/2 and R/2

• Remember, R(h)

9

Tentative Syllabus• April 1: Introduction, team make-up discussion• April 3: Teams finalized, Performance Estimation,

hardware handed out• April 8: Introduction to ArduPilot Mega 2.5• April 10: Electric propulsion, propeller performance,

motor/propeller matching.• April 15: Performance estimation, PS1 Due• April 17: Airfoil and Wing analysis / design• April 22: Intro to S&C, aircraft stability & control• April 24: S&C, basic PID control ideas, other • April 29: Vortex Lattice program/s intro & capabilities• May 1: Lab time, PS2 Due

10

Tentative Syllabus (II)• May 6: Mission planning• May 8: Mission planning continued (if needed)• May 13: Lab time• May 15: Lab time• May 20: Lab time, PS3 Due• May 22: Final flight discussions• May 27: Lab time• May 29: Lab time• Jun 3 & 5: FLIGHT TRIALS!!!!• Jun 10: Possible flight trials.• June 12: Final reports due• Jun 13: Grades due

11

Some Final Thoughts• Flight test procedures

– See “Do & Do Nots” on course webpage– Please be careful, exercise judgment, and minimize

risks!• Damaged, broken, missing equipment:

– Your team is responsible for the equipment you are issued– Your team is responsible for replacing the equipment that has

been damaged– We may have spare parts that you can borrow immediately, but

your team is responsible for ordering and re-stocking the damage parts

– We want you to think about what you are doing, before you are doing it.

12

Some Help…• Sign up for Stanford AA’s very own UAV club for help

with flying R/C and others goodies

• Mailing list can be found at: uav-students@lists.stanford.edu

13