POE EOC Review Notes

Global Engineering Concepts

• Engineering Ethical Dilemma: Assess ethical considerations in engineering scenarios.

• Engineering Design Process: Explain and justify the steps involved.

• Information Analysis: Collect, analyze, and interpret relevant information to support engineering decisions.

• Problem Definition: Synthesize ill-formed problems into well-defined ones.

• Solution Generation: Generate multiple potential solution concepts.

• Modeling and Testing: Develop models to represent design alternatives, generate data for decision-making, test alternatives, and demonstrate solutions.

• Solution Selection: Choose the best solution from multiple options.

• Investigation: Plan and execute investigations to collect valid quantitative data.

• Experimentation: Design and carry out experiments to investigate research questions and draw conclusions.

• Problem Decomposition: Break down data, problems, and processes into manageable parts.

• Abstraction: Apply abstraction to generalize problems and solutions.

• System Thinking: Consider how engineering problems and their solutions fit into broader systems.

Foundations of Math and Engineering Science

• Mechanical Systems: Measure forces and distances; calculate mechanical advantage, work, power, and efficiency.

• Electrical Circuits: Analyze parallel and series circuits for resistance, current, and voltage using Ohm’s law.

• Free-Fall Motion: Describe free-fall motion.

• Kinematics: Calculate distance, displacement, speed, velocity, and acceleration from data.

• Projectile Motion: Describe the location of a projectile in motion as a function of time.

• Free Body Diagrams: Draw free body diagrams, identifying all forces acting on an object.

• Structural Mechanics: Calculate moment of inertia, beam deflection, and moments or torques.

• Truss Analysis: Analyze and solve for external and internal forces on a truss.

• Tensile Force: Describe how formulas are applied to material loaded with a tensile force.

• Algorithms: Use algorithms to create solutions, with or without computer programs.

• Automation: Formulate solutions that use automation and programming to solve problems.

Engineering Design Principles

• Computational Thinking: Apply computational thinking to generalize and solve problems using computers.

• Simple Machines: Identify appropriate applications and examples of each of the six simple machines.

• Control Systems: Describe differences and advantages of open- and closed-loop systems. Predict the behavior of a control system and use a variety of methods for finding, identifying, and correcting bugs in a program.

• Fluid Power: Design hydraulic and pneumatic devices, calculating design parameters using Pascal’s Law.

• Energy Sources: Explore and document different energy sources and their uses.

• Robotics: Design a robotic system that solves an engineering design problem and meets required constraints and criteria.

• Automation and Robotics: Describe the purpose of automation and robotics and their effect on society.

• Modeling and Simulation: Develop models and simulations to represent information, processes, and/or objects to an appropriate level of abstraction for the intended purpose.

Engineering Design Process

• Define the Problem

  • Create a design brief including client, consumers, designers, problem statement, design statement, constraints and controls

  • Define success criteria

• Generate Concepts

  • Conduct research of current solutions

  • Brainstorm ideas

  • Create decision matrix to select idea

• Develop Solution

  • Justify solution

  • Create a detailed sketch or CAD model of solution

• Construct and Test

  • Build or create solution

  • Develop valid test to test your solution

  • Complete multiple trails of tests

  • Document results from your test

• Evaluate Solution

  • Reflect on design solution

  • Recommend improvements to design

  • Define further testing that may need to be conducted

  • Redesign the solution if needed

• Present Solution

  • Communicate the solution to others

Simple Machines

• Types:

  • Inclined plane

  • Wheel and axle

  • Lever

  • Pulley

  • Screw

  • Wedge

• IMA (Ideal Mechanical Advantage)

  • Based on design and distance

  • $IMA = DE / DR$

    • DE = Distance Effort

    • DR = Distance Resistance

• AMA (Actual Mechanical Advantage)

  • Based on actual forces

  • $AMA = FR / FE$

    • FR = Force Resistance

    • FE = Force Effort

• Can use IMA to determine ideal effort force by setting IMA equal to AMA equation

Gear Ratio

• Higher gear ratio indicates higher torque/lower speed
  Gear Ratio = teeth_in / teeth_out = diameter_in / diameter_out = rpm_out / rpm_in

Work, Power, and Efficiency

• Work: $Work = Force \cdot distance$

• Power: $Power = \frac{work}{time}$

• Efficiency: Efficiency = (power out / power in) x 100

Series Circuits

• Current is the same throughout.

• Resistance increases with more resistors: RT = R1 + R2 + R3

• Voltage for each resistor decreases with more resistors

• A break in the line shuts off all motors/lights, etc.

Parallel Circuits

• Voltage is the same throughout.

• Total resistance decreases with more resistors: (1/R_T) = 1/R₁ + 1/R₂ + 1/R₃ …

• Current increases as more resistors are added.

• A break in the line can allow other motors/lights, etc., to remain on.

Ohm's Law

• $V = IR$

  • V = Voltage (in volts)

  • I = Current (in Amps)

  • R = Resistance (in ohms)

Free Fall

• Objects fall with acceleration due to gravity (9.8 m/s² or 32.2 ft/s²).

• Gravity always causes objects to accelerate downward at a constant rate. If the object has an initial velocity upwards, it will slow down first, then change direction

Distance, Displacement, and Acceleration

• Distance is how far an object has traveled, regardless of direction.

• Displacement is a vector value. How far an object has traveled from where it started, includes a magnitude and direction.
  $Displacement = final \ location - initial \ location$

• Acceleration is the rate of change in velocity: a = (vf-vi)/t

Projectile Motion

• Objects have both x and y components of motion.

• If it starts and ends on the ground, the change in the y-direction is 0.

• Use kinematics equations for x and y components.

• The y-direction can be solved for time, then applied to the x component to determine horizontal displacement in many cases.

Free Body Diagram

• Arrows directed away from the object.

• All forces labeled and known values given.

• Can use to calculate net force.

• Objects that are not accelerating are in equilibrium, so all forces must cancel out.

Moment of Inertia

• Moment of Inertia is dependent on the shape of the object (equation varies by shape).

• A higher value indicates it is more difficult to begin rotating or stop rotating.

Moment of Torque

• $Moment = force \cdot perpendicular \ distance$

• Counterclockwise is positive, clockwise is negative.

• Non-moving object sum of the torques = 0.

Beam Deflection

• How much a beam/board bends when a force is placed on it.

• Dependent on layout, amount of force, moment of inertia, and length of the span.

Truss Calculations

• Static Determinacy - truss forces can be calculated.

• To determine: $2J = M + R$

  • J = number of joints

  • M = number of members

  • R = amount of reactionary forces

    • Roller = 1 reactionary force

    • Pin = 2 reactionary forces

• When in tension, member forces are directed toward the center of the member/beam.

• When in compression, member forces are directed away from the center of the member/beam.

Programming

• Be able to follow programming logic and flow charts, including if, if else, and else statements.

• Identify how to fix errors in code (indentation, punctuation, sequence of commands).

Open vs. Closed Loops

• Open loops do not respond to the environment/things around them and continue regardless of what is going on around them.

• Closed loops respond to the environment/things around them.

Hydraulics and Pneumatics

• Pressure change at any point in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere: F1/A1=F2/A2

• Hydraulics use liquids such as hydraulic fluid.

  • Hydraulics tend to be stronger and more precise but can be messier and slower to act.

• Pneumatics use air, which takes time to compress.

  • Pneumatics are faster-acting (once air is compressed) and cleaner but not as strong or precise.

Engineering and Business Ethics

• Be prepared for engineering and business ethical questions.

Engineering and business ethics are critical components of responsible practice in both fields. Engineers are often faced with decisions that have significant impacts on public safety, environmental sustainability, and overall welfare. Ethical guidelines provide a framework for navigating these complex situations, ensuring that engineers prioritize the well-being of society over personal or corporate gain. These guidelines often include principles such as honesty, impartiality, and a commitment to upholding professional standards.

In the business world, ethical conduct is essential for building trust with stakeholders, including customers, employees, and investors. Business ethics involve making decisions that are not only profitable but also morally sound and socially responsible. This can include issues such as fair labor practices, transparent financial reporting, and avoiding conflicts of interest. Companies that prioritize ethical behavior often find that it leads to long-term success and a positive reputation