ME08

Enduring Understandings
Robots are mechanical devices that can autonomously accomplish routine tasks. In doing so, they incorporate a variety of simple machines, which combine to form a compound machine. Robots typically use an electrical motor, but that motor can multiply the force of the motor or multiply its speed, depending on how it is connected. In each case, there is a tradeoff between the force and the speed, i.e., both cannot be multiplied simultaneously. Many forms of technology, like robots, combine these simple machines into a compound machine. In this section, you will learn to find them and study their purpose in the workings of the device.

Learning Objectives: Students will be able to...

 * Design or evaluate simple technological or natural systems that incorporate the principles of force and motion (e.g., simple machines, compound machines).
 * Calculate the mechanical advantage for moving an object by using a simple machine.
 * Identify elements of simple machines in compound machines.
 * Calculate the efficiency of a simple machine.

Working Draft Learning Learning Activities/Strategies/Technologies

 * Simple Machine Experiments
 * Simple Machines Lab Kits
 * Online Gear Simulations
 * Rube Goldberg Project
 * Online Rube Goldberg Simulations
 * Calculating Mechanical Advantage
 * Online Mechanical Advantage Simulations
 * Calculating Efficiency

Supplemental Resources:
Cox Lesson #1 : Lever Arm Concept--Lever Investigation Cox Lesson #2 : Mechanical Advantage--Notes, Calculations Cox Lesson #3 : Six Machines (MA)--Notes, Demos (Stations) Cox Lesson #4 : TMA/AMA/Efficiency--Notes, Calculations Cox Lesson #5 : Compound Machines--VCR Investigation Cox Lesson #6 : Engineering Challenge--Gear/Car Kits Newhart Lesson: Simple Machine Scavenger Hunt Other Resources: On the hs-data drive, I placed a jeopardy game and chapter test I used with my honors students. http://science.howstuffworks.com/robot.htm http://science.howstuffworks.com/gear.htm http://science.howstuffworks.com/pulley.htm http://www.rubegoldberg.com/ http://www.youtube.com/watch?v=q8DjQ2DXs7s http://www.scienceyear.com/under11s/index.html?page=/under11s/levers/index.html -Great Lever Explanation! http://www.popularmechanics.com/outdoors/adventures/3886757.html Trebuchet Plans Text Science Spectrum Ch 8.1 & 8.2 Simple Machines & MA; CH 8.4 Energy [|Gear Activity] Gear Ratio Car Kits [|Toys] http://www.ieee.org/web/education/preuniversity/tispt/lrobotarm.html [|Great online RGD ( link courtesy of J. Kellett)] http://www.steelcitysfinest.com/HondaAccordAd.htm http://www.cosi.org/files/Flash/simpMach/sm1.swf http://scifiles.larc.nasa.gov/kids/Problem_Board/problems/pulleys/sim1.swf http://pbskids.org/zoom/games/goldburgertogo/index.html
 * [|Robot Arm Simulation]
 * Gear Ratio Car Investigation

Instructional Objectives: Students will be able to...
//Simple Machines (Force/Distance Tradeoff)// //Mechanical Advantage (Multiplying speed or force)// Ch 8.1 //Energy & Efficiency (First & Second Law of Thermodynamics) Ch 8.4// //Compound Machines// (only page 262 defined) //Flowcharts of Energy Transfer//
 * identify and measure the input and output forces of simple machines.
 * identify and measure the input and output distances of simple machines.
 * describe the effect of increasing output distance or input distance on the output force of a simple machine.
 * Calculate the mechanical advantage of moving an object using a simple machine.
 * Evaluate the elements of a simple machine in terms of their ability to multiply force or speed.
 * explain the operation of a simple machine in terms of energy conservation.
 * identify parts of a simple machine that result in inefficiency.
 * Identify elements of simple machines in compound machines.
 * Design a compound machine that incorporates a variety of simple machines.
 * create a flowchart showing the energy transformations in a compound machine.

**Prior Learning (from S8 Anchors):**
S8.C.3.1 Describe the effect of multiple forces on the movement, speed, or direction of an object.
 * S8.C.3.1.1 Describe forces acting on objects (e.g., friction, gravity, balanced versus unbalanced).
 * S8.C.3.1.2 Distinguish between kinetic and potential energy.
 * S8.C.3.1.3 Explain that mechanical advantage helps to do work (physics) by either changing a force or changing the direction of the applied force (e.g., simple machines, hydraulic systems).