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Title: Penn State


1
Penn State Autonomous System Navigation, Driver
Augmentation Engineering Project Kickoff March
03, 2008
2
Kickoff Agenda
  • Introduction to the Project
  • Overview of project steps
  • Modeling and Simulation
  • CONOPS (CONcept of OPerationS) Development
  • Requirements Development
  • Concept Generation
  • Concept Development
  • Concept Presentation
  • Summary
  • Appendices Back-up material
  • Questions and Discussion

3
(No Transcript)
4
Project Statement
  • Problem statement
  • In the US, Motor vehicle accidents are the
    leading cause of death for people between 1 to 34
    years old. (National Vital Statistics report,
    September 2002.)
  • In spite of advanced structural design of
    automobiles, crumple zones, air bags, etc., the
    death rate has reached a non-zero asymptote.
  • WHY?
  • The answer lies in the fact that current
    technology fielded is reactive and not
    pre-emptive.
  • Devices react to the accident, they do not
    prevent the accident from occurring in the first
    place.
  • More warning time and intervention on the part of
    a driver assist system can prevent accidents or
    provide additional warning time to, in fact,
    implement better safety devices.
  • This problem is particularly acute for certain
    situations. Consider
  • Convoy duty requires close vehicle spacing at
    high speeds often on damaged or unimproved road
    surfaces.
  • Drivers are often called upon to maintain
    position during periods of high stress.
  • When under attack, during black conditions, or
    during high speed maneuvering.
  • Reaction time is compromised by external
    distractions.
  • A system which detects and regulates a vehicles
    position as well as monitoring road conditions
    when traveling at high speed could result in a
    significant reduction in accidents and serious /
    fatal injury.
  • Frees up the crew to concentrate on all mission
    aspects.
  • This technology is directly applicable to modern
    highway driving.

5
Project Statement
  • Objective
  • Develop a method to detect and avoid obstacles
    while maintaining formation.
  • Define technique to be utilized, I.e. radar,
    ladar, thermal imaging, spectroscopy, etc.
  • Design system to detect presence of vehicle,
    determine range, velocity, position and maintain
    formation during convoy operations.
  • Display warning and suggested collision avoidance
    method to driver.
  • Detect on-coming traffic and factor into decision
    process.
  • Background
  • Your team is employed by a specialty engineering
    firm
  • The firm has been contracted to develop Driver
    Assist concepts for convoy vehicles.
  • The customer has awarded several contracts to
    competing firms and will ultimately select the
    best concept for a lucrative development,
    production, and fielding contract.
  • HMMWV upgrade
  • This is a real problem with real impact in
    todays world
  • Direct leverage into commercial markets.
  • BMW, Mercedes, GM, Ford, Toyota are all invested.
  • Solving it literally makes people safer on the
    road
  • There are many other practical application areas
    for this technology.

6
Project Statement Of Work (SOW)
  • Tasks Your firm will need to
  • Perform a customer needs assessment based on your
    interpretation of the problem scope.
  • Develop an initial Concept Of Operations (CONOPS)
  • The CONOPS is essential and defines how your
    system will actually operate.
  • Your CONOPS will evolve as your system
    architecture matures.
  • Develop a draft of your system specification.
  • This will evolve as your system architecture
    develops
  • Research sensor types currently available.
  • Some data on typical sensors is provided for a
    reference
  • Dont forget the display type for the driver and
    how the system integrates the human in the loop
  • Perform trade studies on the type and quantity of
    sensors, type and quantity of vehicles required,
    how the vehicles are employed, and information
    provided versus cost.
  • Design a system using the results of the trade
    studies including optimal sensor placement,
    integration with the vehicle, etc.
  • Calculate size and mass properties impact of the
    sensor system (including the display).
  • Check out the DARPA Urban Grand Challenge
    project. This provides an excellent overview of
    the ultimate robotic driving problem today and
    the complexities you will face.
  • Fortunately your problem is much less complex!
  • Remember that you cant displace the passengers
    or cargo completely and you must integrate the
    driver into the picture.
  • Develop the cost to field the system. I.e.,
    number and type of vehicles, number of sensors,
    etc.

7
Project Approach
  • This project will lead you through a disciplined
    systems engineering approach to engineering
    concept development
  • Perform a customer needs assessment.
  • Understand the problem via hand analysis,
    modeling, and simulation
  • Develop the requirements for your system concept
  • Generate ideas for the Driver Assist system
    concept
  • Refine the ideas through concept development
  • Select your best concept and develop it in detail
  • Develop your CONcept of OPerationS (CONOPS)
  • Assess your systems strengths and weaknesses
  • Sell your final idea to the customer
  • Tools you will use Mathematics, physics,
    spreadsheets, brainstorming, trade studies, CAD,
    presentation SW
  • The tools support your creative process

A-1
Additional Information on Project Approach is
provided in Appendix
8
Driver Assist Problem Statement
  • Requirements
  • Maintain formation of three HMMWVs under
    blackout conditions.
  • Determine the best method of station keeping and
    obstacle avoidance.
  • The obstacle is a large crater in the road
    capable of inflicting damage to the lead and
    following vehicles.
  • Crater dimensions 1 meter wide and deep, 2
    meters in procession direction. Aligned with
    passenger roadside.
  • You must detect the crater and maneuver around it
    in time.
  • Assume convoy velocity is 50 km/hr
  • There may be on-coming traffic so you must detect
    and declare / decide before you maneuver.
  • Must determine total time to complete avoidance
    maneuver for entire procession
  • You must notify driver using method of your own
    design
  • Alert following vehicles of impending maneuver
  • Can not throw occupants from vehicle
  • Must calculate accelerations induced on occupants
    from avoidance maneuver

Crater
9
HMMWV Information
  • HMMWV High Mobility Multipurpose Wheeled
    Vehicle
  • M998 Variant
  • Replacement for venerable M151 JEEP
  • Turning radius 8.07 meters
  • Maximum g load during turn 1.3 gs
  • Maximum longitudinal acceleration 0.17 gs

http//www.globalsecurity.org/military/systems/gro
und/hmmwv.htm
10
HMMWV Operational Configuration
A-2
Additional data on HMMWV is provided in Appendix
11
DARPA Grand Challenge Configurations
Filling the entire vehicle with sensors is
unacceptable for a variety of reasons
The 2005 Mitre Sponsored Car for the Darpa
Challenge
The 2005 Stanford Racing Teams Car, Winner of
2005 DARPA Challenge
The 2007 Carnegie Mellon Urban Challenge Vehicle
The 2007 MIT Urban Challenge Vehicle
http//www.darpa.mil/GRANDCHALLENGE/overview.asp
12
Notional Project Schedule
  • Illustrated below is an example task breakdown
    for this project.
  • Your faculty advisor will tailor / facilitate
    your specific tasking and scheduling

Week
1
2
3
4
5
6
7
8
Modeling and Simulation
CONOPS Development
Requirements Development
Concept Generation
Concept Analysis/Selection
Concept Presentation
13
Modeling and Simulation
Week
1
2
3
4
5
6
7
8
Modeling and Simulation
  • Outputs
  • Parametric planar vehicle model
  • Maneuver definition
  • Sensor coverage using defined FOV
  • Physical understanding of problem

CONOPS development
Requirements development
  • Inputs
  • HMMWV Background Info
  • Sensor Information
  • Obstacle avoidance maneuver
  • Modeling approach
  • Modeling equations
  • Model inputs (constants)
  • Self-check tools

Concept Generation
Concept Analysis/Selection
Concept Presentation
14
Modeling and Simulation Scenario
  • Apply Newtonian physics to develop a
    mathematical, parametric model of the HMMWV
    convoy over the terrain and the maneuver required
  • Kinematics is the general class of physics that
    will be applied
  • Modeling Objectives
  • Determine maneuver required to avoid obstacle.
  • Calculate forces on crew and vehicle
  • Determine which sensors best meet your mission
    needs in terms of obstacle detection and warning
    / maneuver initiation
  • Your CONOPS will be critical to the modeling and
    may change / evolve based upon your results
  • Gain a physical understanding of the sensor
    coverage requirements.

Hint approximate your road and vehicle model as
a set of straight line segments then define your
maneuver path. Use this to calculate sensor
requirements
8 m
8 m
2.16 m
1 m
5 m
2 m
4.57 m
TBD m
5 m
4.57 m
4.57 m
15
Mathematical modeling
  • Develop model using kinematics equations,
    constants, variables, and desired outputs
  • Constants
  • Values that will not change for the model
  • Road dimensions
  • Obstacle parameters
  • Vehicle physical dimensions
  • Provided in Appendix
  • Outputs
  • Values that you will determine via the model
  • Quantity of sensors required, sensor type
    employed.
  • Will be determined as a function of the input
    variables
  • i.e. Range to obstacle vs. time, velocity,
    acceleration, etc.

A-3
  • Equations
  • Kinematics equations provided in Appendix
  • Variables
  • Values that you will vary over a range to
    determine flyout times
  • Vehicle velocity
  • Centripetal acceleration
  • Sensor type
  • Detection range
  • Provided in Appendix

A-5
A-4
16
Model development
What I cannot create, I do not understand."
Richard Feynman, theoretical physicist
  • Step 1 Work the problem a few times
  • by hand
  • Treat it like a homework assignment
  • For example How many sensors are required to
    detect the obstacle? What coverage do they
    provide, what type of sensor overlap is required,
    are you going to mix sensor types to optimize
    coverage, does the total system meet your cost
    expectations?
  • How will I model the system to verify
    performance?
  • Make sure that the relationships make sense in
    terms of your trade space.
  • Dont forget that detecting the obstacle is not
    the only requirement.
  • Remember the following vehicles.
  • Step 2 Put the equations (or assumptions) into a
    computer tool so you can vary the inputs over a
    range and plot relationships
  • Tools Custom computer program, Excel, MatLab,
    MathCad, etc.
  • Now the variables become ranges of values
  • The answer is the plotted relationships and a
    physical understanding of the maneuver dynamics

A-6
Additional suggestions to Model development are
provided in Appendix
17
Sample Preliminary Hand Analysis
Discretized maneuver, blue, solid
  • Consider a hypothetical radar based solution
  • Need to calculate number of radar sensors
    required and basic maneuver requirements
  • Must consider sensor field of view
  • Simple geometric approximations will suffice
  • Remember complexities may be subtle
  • For example, suppose you chose a really
    inexpensive short range sensor. Do you exceed
    the maneuver limits of the HMMWV?
  • Clearly the ground track (and resulting
    acceleration requirements), must be approximated
    as a series of straight line segments using
    simple geometric relationships.
  • During your model build up remember
  • This is tied directly to your CONOPS
  • May Consider multiple types of sensors to solve
    problem
  • Must consider vehicle parameters
  • Use model to determine type, and quantity of
    sensors, speed reduction of vehicles (if
    necessary), maneuver loads and cueing for next
    vehicle in procession.

S9
S8
S7
S6
  • 9 segments in this example.
  • Calculated angles based on encounter geometry
    determines required sensor field of view
  • Velocity of convoy and radius of curvature sets
    acceleration.
  • Best approach will fuse multiple sensor
    modalities.

S5
S4
S3
S2
S1
A-7
Additional information on sample model outputs
are provided in Appendix
A-8
Tips on model/simulation are provided in Appendix
18
CONOPS Development
Week
1
2
3
4
5
6
7
8
Modeling and Simulation
  • Outputs
  • Definition of your approach for system operation
  • Preliminary list of required operational
    capabilities

CONOPS Development
Requirements development
  • Inputs
  • Sensor equipment parameters
  • Vehicle parameters
  • Maneuver approach concept
  • Brainstorming technique resource

Concept Generation
Concept Analysis/Selection
Concept Presentation
19
Requirements Development
Week
1
2
3
4
5
6
7
8
Modeling and Simulation
  • Outputs
  • Tables/graphs
  • Response performance for given sensor embodiment

CONOPS Development
Requirements Development
Concept Generation
  • Inputs
  • HMMWV Operational Parameters
  • Sensor parameters

Concept Development
Concept Presentation
20
Development Process
  • The customer is primarily concerned with convoy
    obstacle avoidance techniques which do not
    compromise vehicle speed
  • Your driver assist system must detect and monitor
    road conditions and trailing vehicle position
  • Developing the timeline requirements means
    filling in this table using your model
  • Outputs
  • Show Range of Times to Respond by using
    Table/Graph

A-9
Tips on development process (e.g. establishing
system timeline) are provided in Appendix
21
Concept Generation
Week
1
2
3
4
5
6
7
8
Modeling and Simulation
  • Outputs
  • Complete list of brainstormed concepts (25
    items)
  • Initial refinement of list (5 items)

CONOPS Development
Requirements Development
Concept Generation
  • Inputs
  • Response-time/maneuver requirements for HMMWV
  • Brainstorming technique resources
  • Sensor equipment and timelines

Concept Development
Concept Presentation
22
Your Job!
  • Basic obstacle detection model is applicable to
    all types of sensor implementations. Use it to
    help define system and refine CONOPS.
  • Detect obstacle
  • Issue Warning
  • Calculate time to go
  • Develop and implement maneuver
  • Assess Next Action
  • Customer has specified a variety of detection
    sensors for your use
  • Can be used in any quantity and configuration at
    the expense of cost, size, weight and power
  • See Appendix for sensor system
    selection guidelines
  • See Appendix for sensor parameter
    information
  • Option available to select your own sensors. Not
    limited by information provided within this
    document but must be based on actual performance.
  • Your job is to come up with the actual obstacle
    detection system approach and concept of
    operations

A-10
A-11
23
Engineering Creativity
  • Apply group creative techniques to develop a rich
    set of possible solutions
  • See resource material on brainstorming and other
    creative techniques, Appendix

"The way to get good ideas is to get lots of
ideas and throw the bad ones away." Linus
Pauling, chemist Nobel Prize Winner
A-12
  • Session 1 Develop a large set of possible
    solutions (25). At this point, dont critique -
    just record the ideas.
  • Session 2 Cull the list down to 4 or 5 solutions
    as a group
  • Use your understanding of the engagement to
    eliminate the weakest solutions
  • Tip Consider the type of detect/cueing sensor(s)
    that will be needed for each obstacle avoidance
    system concept (i.e. a very cheap simple sensor
    may require a vast number but may still be less
    expensive than a smaller number of sophisticated
    sensors.) Consider system level impacts, e.g.,
    maneuver loads on vehicle.

24
Concept Development
Week
1
2
3
4
5
6
7
8
Modeling and Simulation
  • Outputs
  • Selected obstacle avoidance system approach
  • Rationale for selection
  • Analysis of performance
  • Sketches/description of concept

CONOPS Development
Requirements Development
  • Inputs
  • Short list of candidates
  • Trade study technique resources
  • Model/analysis tools
  • CAD resources

Concept Generation
Concept Development
Concept Presentation
25
Engineering Selection
  • Selection of the optimal obstacle avoidance
    system requires that you further develop each
    idea on the short list
  • Further development should focus on answering the
    key questions
  • Will it be effective?
  • How big will it be, what will it weigh, how much
    power does it take?
  • What type and quantity of sensors are required?
  • How much will it cost?
  • Is it feasible?
  • Use CAD to sketch your concepts and visualize
    installation
  • Use your model (possibly with modifications) to
    determine the effectiveness

26
Trade Studies
  • Once you have sufficiently developed the
    alternatives, conduct an engineering trade study
    to select the optimal approach
  • Trade studies promote objective review and
    selection of the best alternative
  • Frequently used in industry
  • See online resources regarding engineering trade
    studies, Appendix
  • Potential trade study criteria
  • Physical
  • Power, weight, size, quantity, FOV
  • Feasibility
  • Unique technical challenges
  • Cost
  • Performance
  • What implementation stresses the vehicle and
    occupants the least?

A-13
Out of clutter, find simplicity. From discord,
find harmony. In the middle of difficulty lies
opportunity." Albert Einstein
27
Sample Technique Trade Study
  • Approach Single sensor modality for detection
    and avoidance
  • Recognize obstacle and declare.
  • Minimize time line to maneuver.
  • Minimize sensor quantity and type.
  • Secondary functional performance
  • All weather capability, etc.
  • Tabularize sensor performance and assign metrics
    to evaluate
  • Select based on performance and suitability to
    CONOPS

28
Concept Presentation
Week
1
2
3
4
5
6
7
8
Modeling and Simulation
  • Outputs
  • Self-assessment
  • Customer briefing
  • Marketing Brochure

CONOPS Development
Requirements Development
Concept Generation
  • Inputs
  • Selected concept design
  • Self-assessment techniques
  • Sample Customer briefing and marketing brochure

Concept Development
Concept Presentation
29
Final Deliverables
  • Final design briefing
  • This is your opportunity to sell your concept
    to your customer
  • Walk them through your whole process, present
    your chosen concept in detail
  • Will require further CAD work and refinement
  • Physical models are an option
  • The briefing should answer the customers
    questions, see Appendix
  • Brochure
  • Develop a fold-out brochure for your customer to
    take with them
  • Example brochures will be provided
  • Remember thorough engineering solid
    presentation SOLD! Anticipate issues your
    customer may have - incorporate risk mitigation
    factors into your design briefing. See Appendix

A-14
A-15
30
Summary
  • You will use the systems engineering techniques
    presented to propose a solution to a significant,
    real-world problem
  • You will use many relevant engineering tools and
    techniques to facilitate your creative process
  • This briefing provides a kickoff, links, some
    buried hints, and a framework for the project
  • Refer to it and the other course material
    frequently
  • A few tips
  • Take it one step at a time, focus on whats
    currently due
  • You will probably start to have concept ideas
    immediately, write them down, keep your mind open

31
Appendix
32
A-1 Additional Info on Approach
  • The Goal is to determine a way to perform the
    following
  • Design a system which
  • Detects the presence of obstacles directly in
    your path and avoids them. (Options given.)
  • This includes on-coming traffic in the event
    avoidance maneuver crosses lanes.
  • Determine how much time is available to react.
    (Analysis, modeling and simulation.)
  • Determine the proper number and type of sensors
    to employ. (Design.)
  • Based on your calculations of the maneuver
    profile required, sensor coverage, and effective
    warning time.
  • Determine if the system concept was effective.
    (Assessment.)
  • Develop a marketing brochure which highlights
    specific features of the design approach using a
    CAD model of the system.
  • Include a statement of system effectiveness in
    obstacle detection and avoidance.
  • The system design should use building blocks
    provided for specific functions such as obstacle
    detection.
  • Concentrate on the actual system design.
  • Hint Timing and field of view are going to be
    key parameters so focusing on calculating
    parameters related to
  • HMMWV motion path
  • If the HMMWV maintains a certain path, can the
    sensor suite detect obstacles and on-coming
    traffic over a wide enough path to effectively
    maneuver out of the way. Is braking the best
    option under certain scenarios?
  • If the lead vehicle detects an obstacle
    successfully, how will the rest of the convoy be
    notified?
  • Time to go, i.e., how long from detection to
    obstacle impact? This timeline will define the
    system response requirements that must be met.
  • Are multiple solution branches accommodated by
    your system? Where is this logic accounted for?
  • Perhaps under certain conditions maneuvering is
    not possible. Do you have adequate situational
    awareness to tell the difference?.

33
A-2 Additional HMMWV Data
  • The High Mobility Multi-purpose Wheeled Vehicle
    is a light, highly mobile, diesel-powered,
    four-wheel-drive vehicle that uses a common 4,400
    lb payload chassis. Using common components and
    kits, the HMMWV can be configured to become a
    troop carrier, armament carrier, S250 shelter
    carrier, ambulance, TOW missile carrier, and a
    Scout vehicle. The 4,400 lb variant was developed
    as the prime mover for the light howitzer, towed
    VULCAN system, and heavier shelter carriers. It
    is a tri-service program that also provides
    vehicles to satisfy Marine Corps and Air Force
    requirements.

34
A-3 Defined Constants
  • Roadway Divided, 8 m / side, no lighting
  • Obstacles
  • Crater 2 x 1 x 1 meters
  • Oncoming vehicles 45 mi/hr, 0.05, 0.1, 0.25, 1
    km distant.
  • Standard day conditions (density, temperature,
    pressure)
  • Assume
  • Multiple scenarios in terms of oncoming traffic
  • Remember to convert dimensions so they are
    consistent

35
A-4 Variables
  • HMMWV parameters are all variable
  • Forward velocity
  • Turn radius (up to specified limit)
  • Longitudinal acceleration (up to specified limit)
  • Mix / qty of sensors can be tailored to your
    CONOPS
  • Method of notification of following vehicles is
    your option
  • Recommend parametrically varying each of these
    parameters ? 10 while holding the others
    constant in order to assess the effect on your
    system design.

36
A-5 Helpful Equations
  • The following may prove useful and are basic
    planar equations of motion found in your physics
    text
  • Vx Vx0 axt
  • Vy Vy0 ayt
  • X X0 Vx0t ½ axt2
  • Y Y0 VY0t ½ aYt2
  • C (a2 b2)1/2
  • ? tan-1(a/b)
  • ? V/R
  • a V2/R
  • Notes
  • Limit maximum acceleration to 1.3 gs
  • Consider only planar geometry
  • Use Euclidian geometry to discretize terrain

37
A-6 Suggestions to Model Development
  • In order to calculate the HMMWV trajectory, the
    equations (provided in A-5) may be used in a
    simple commercial software (such as Excel,
    MatLab, MathCad, Fortran, or C) to calculate all
    necessary geometry and timing parameters
    associated with the ground track.
  • Once the basic simulation is running, the
    equations can be further built up and more can be
    added to model any specific approach to include,
    for example,
  • Effect of multiple oncoming traffic
  • Effect of convoy velocity changes.
  • Timing studies to optimize number and type of
    sensors.
  • The basic equations provided can be modified to
    include all vehicles in the convoy and can be run
    parametrically (automated using user defined rule
    set) until the desired operational profile and
    mix of sensors is achieved.

38
A-7 Sample Model Outputs (Continued)
  • Consider multiple sensor modalities
  • FOV 0.14 radians (from sensor table)
  • V 50 km/hr
  • Step 1 Calculate ground track check against
    model
  • Step 2 Calculate maneuver loads impressed on
    vehicle
  • Step 3 Calculate timing for trailing HMMWVs in
    procession
  • Step 4 Examine sensor field of view implications
    for your planned implementation
  • Ask yourself, what does this tell me?
  • Ex Spatial gaps during driving due to timing
    must be filled through addition of sensors
  • Can I detect adjacent vehicles with this
    embodiment for the spacing specified
  • Remember, your model must match your hand
    calculations.

39
A-8 Tips on Model/Simulation
  • If your code is running correctly, the maneuver
    track, timing, and sensor coverage vs. time can
    now be determined.
  • The simulation can also be used to perform trade
    studies designed to optimize your system design
    and response.
  • In order to check the code, try calculating the
    time to cover a straight ground track without any
    maneuver and comparing the X, Y, and timing
    against your hand calculations.
  • Then set the maneuver to a very small offset.
    The results should compare with the timing being
    slightly longer due to the increased path length.
  • An additional suggested check of the simulation
    is to verify that the units of all calculations
    are consistent and the results are expressed
    correctly.
  • Use dimensional analysis for this.
  • At the conclusion of the modeling and simulation
    stage of the project, the following questions and
    milestones should be met
  • A simple, X-Y planar, parametric model of the
    HMMWV trajectory enabling physical trade studies
    to be performed should be available.
  • Given that the detection of the obstacle is
    assured (I.e., zero false alarm rate.)
  • Based on selection of the detection sensors,
    what is the time line for location, notification,
    and avoidance maneuver implementation?
  • Suggestion use timing chart supplied as a
    template and fill in using data generated with
    model.
  • Determine if the system functions in the presence
    of oncoming traffic or if further modifications
    to the convoy procession are required.
  • If so, what changes to formation are required
  • What changes to system response time could
    improve performance.
  • I.e., what is the functional time allocation to
    the various parts of the system design and is it
    correct.
  • Do you need more than a single type of sensor?
  • What type of accuracy is needed and what is the
    cost impact?

40
A-9 Basics of HMMWV Obstacle Avoidance System
Timeline
  • In order to design an effective obstacle
    avoidance system, an understanding of basic
    functional requirements, for example timing, is
    required. You will have to modify the function
    listing based on system design however this forms
    a minimal requirement set.
  • Typical time from detection of the obstacle for a
    range of ? km is between ? and ? seconds for the
    proposed geometry
  • Preliminary allocation of time line based on a
    threshold value of ? sec and a goal of ? sec can
    be used to estimate approach viability / develop
    functional requirements.
  • Function Threshold Goal
  • Detect declare obstacle --------- ----
  • Issue warning --------- ----
  • Calculate time to maneuver --------- ----
  • Initiate maneuver --------- ----
  • Assess Next Action Leave out of timeline, but
    consider
  • implications of next actions, e.g. acquire
    and track a second obstacle.

41
A-10 Obstacle Avoidance System Guidelines
  • The chart in Appendix A-11 provides data on
    potential sensor systems available to you as the
    designer.
  • Assume that the following functions are performed
    by any of the system options given on the chart.
    The system will
  • Identify and calculate direction of obstacles
    within limits prescribed.
  • Issues warning of obstacle and sends message to
    your command post.
  • Ideal false alarm rate ? Pfa 0.0
  • Cost includes integrated electronics to fuse
    sensor, ID function, and transmitter.
  • Rules
  • For RADAR and IR Sensor better angular
    accuracy, if required, can be achieved with
    addition of more sensors (electronics) at
    increased cost and volume. Assume 15 increase
    in , 10 increase in weight, 2x sensors qty
    for each doubling in angular accuracy. Assume no
    penalty in detection time or track development
    due to internal system architecture.
  • Use of multiple sensor types is allowed.
  • Acoustic sensors do not provide bearing to
    intruder, only presence in hemisphere defined by
    diameter equivalent to maximum detection range.
  • Increasing the scanned area by the LIDAR requires
    the addition of multiple units at a 1/1 cost,
    weight, and volume penalty for each unit
    employed.
  • UV Sensors provide hemispherical coverage at the
    elevation angle defined.

42
A-11 Sensor Systems Provided by Customer
43
A-12 Creativity Resources
To have a great idea, have a lot of them."
Thomas A. Edison
  • Some web resources on creative techniques
  • http//www.brainstorming.co.uk/tutorials/tutorialc
    ontents.html
  • A comprehensive tutorial on brainstorming and
    other creative techniques
  • http//www.effectivemeetings.com/teams/participati
    on/brainstorming.asp
  • A pragmatic summary of how to setup and run a
    brainstorming session
  • http//www.promato.com/brainstorm/bslinks.htm
  • A free trial download of a brainstorming and
    selection facilitation program

44
A-13 Trade Study Examples
  • Trade study examples on the web
  • http//www.faa.gov/asd/SystemEngineering/SEM3.0/fo
    ur_six20.pdf
  • A very detailed look at the systems engineering
    process and at conducting trade studies (Starts
    on line 27)
  • http//www.losangeles.af.mil/Tenants/SCEA/CAIV18M/
    reqtrade40.ppt
  • A presentation of a simple CAIV (Cost As an
    Independent Variable) trade study, a lot of
    acronyms, most of the good stuff starts on pg 8

45
A-14 Key customer questions
  • Key Customer questions
  • How did you arrive at your timeline and what is
    it?
  • Simplifying assumptions you made why are they
    valid?
  • What was your creative process?
  • Present all of your brainstormed ideas and the
    context of your brainstorming session?
  • Why did you select the chosen design?
  • Have you presented the results of key trade
    studies conducted?
  • Have you provided evidence that the concept is
    effective?
  • Which obstacle avoidance scenarios can be met
    successfully?
  • Which ones present risk? (How does oncoming
    traffic effect implementation?
  • Is your solution realizable, affordable,
    realistic?
  • Can your system react to more than one obstacle
    simultaneously?
  • Are there any safety related effects from your
    obstacle detection system design, for example,
    LIDAR eye safety?
  • Human life, property?
  • What ethical issues have been considered?
  • How long from start to develop and field your
    solution?
  • Will it work in a range of outdoor environments?
  • hot, cold, snow, sand, rain, etc.?

46
A-15 Assessing Your Offering
  • You will need to perform a critical
    self-assessment of your offering -
  • before your customer does. Here are some
    questions to consider
  • Available technologies.
  • What type of technologies can be utilized? Need
    to be utilized?
  • Does it exist and how can it be adapted to this
    problem?
  • Enabling technologies requiring further
    development
  • What needs to be invented?
  • Is it physically possible?
  • Cost prohibitive?
  • What is the system configuration?
  • Is it compatible with the intended user.
  • Size, cost, etc.
  • Does the system specified meet the goal of
    detecting the target?
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