Engineering Design

Lesson 1: What is the Engineering Design Process?

What Is the Engineering Design Process?

Materials

Group Size

2-3 students

Suggested Time

40-60 minutes

Background  

An engineer is any person who designs and builds things to solve practical problems. There are many types of engineers: civil, electrical, mechanical, software, aerospace, etc. There is a series of steps that all engineers follow when they’re trying to solve a problem. This process is called the engineering design process —— a systematic problem-solving strategy, with criteria and constraints, used to develop many possible solutions to a problem, so as to satisfy human needs and wants. The engineering design process is informed by many factors such as human values, available resources, environmental concerns, and trade-offs in order to reach an optimal solution to the problem. During the design process, engineers:

  1. identify the problem
  2. do background research
  3. imagine possible solutions
  4. plan by selecting a promising solution
  5. build a prototype
  6. test and evaluate the prototype
  7. improve and redesign as needed

The engineering design process is an iterative where multiple failures come before the final success. Engineers repeat the steps as many times as needed to make improvements and explore different possibilities, and that’s how great solutions are created.

Learning Objectives 

Students will be able to:  

  • Identify and explain the steps of the engineering design process
  • Invent a solution using the first few steps of the engineering design process

Standards Alignment

NGSS: HS-ETS1-2: Design a solution to a complex real-world problem by breaking it down into smaller, more manageable problems that can be solved through engineering.

  • Science and Engineering Practices: Constructing Explanations and Designing Solutions: Design a solution to a complex real-world problem, based on scientific knowledge, student-generated sources of evidence, prioritized criteria, and tradeoff considerations.
  • Disciplinary Core Ideas: ETS1.C: Optimizing the Design Solution: Criteria may need to be broken down into simpler ones that can be approached systematically, and decisions about the priority of certain criteria over others (trade-offs) may be needed.

CCSS: ELA-LITERACY.WHST.9-12.7: Conduct short as well as more sustained research projects to answer a question (including a self-generated question) or solve a problem; narrow or broaden the inquiry when appropriate; synthesize multiple sources on the subject, demonstrating understanding of the subject under investigation.

Basic Outline

Engage (Slides 3-4)

Tell students that an engineer is any person who designs and builds things to solve practical problems. There is a series of steps that all engineers follow when they’re trying to solve a problem. This process is called the engineering design process. Explain to students that during this class, they will identify the steps of the engineering design process and consider how to solve a problem using the first few steps of the process.

Explore (Slides 5-6)

Ask students to complete section one in their Lab Notes handout and think about why engineers should do things in order.

Students will:

  1. Sort the steps of the engineering design process.
  2. Determine which description corresponds with which step.
  3. Write out each description in the appropriate box.
Explain (Slides 7-17)
  1. Explain to students the engineering design process.
  2. Tell students that the steps of the engineering design process help support the design, construction, and refinement of a product or a system. The process is iterative. Engineers repeat the steps as many times as needed, making improvements along the way as they learn from failure and uncover new design possibilities to arrive at great solutions.
  3. Ask students to think about the way a prosthetic hand looked in the past compared to what it looks like now. Engineers had to come up with thousands of different ideas and designs to be sure the prosthetic hand can be used safely, effectively, and looks good. Show more examples to illustrate the engineering design process.
Elaborate (Slides 18-23)

Explain to students that during this activity, they will be asked to exercise their creative problem-solving skills using the first few steps of the engineering design process. Students will work as engineers and consider how to solve one of the problems below. To save time, students can do some preliminary evaluations without building a device.

Engineering problems:

    • Soda overflowing is surely annoying. When you open a can of the bottle during hot summer noon, the liquid just flows out because of expanding carbon dioxide. Now you not only have less soda to enjoy but also stain your clothes. Improve soda bottles or cans to prevent soda overflowing.
    • One of your friends is visually impaired. When your friend gets to the bus stop, it’s really hard for him/her to tell if the bus approaching the stop is the one he/she wants to take. Try to design a device to help your friend identify the bus route.
    • It is fun to build your tent during camping, but sometimes it can be tiring to build a tent after a long day of outdoor exercising. Design a tent that could be easily folded (without disassembly) to fit into the trunk of your car, and next time when you go camping, you don’t have to worry about building a tent.
    • GPS enhances the driving experience. It directs by telling the user how far ahead the next turn is, but sometimes a driver can still miss a turn or make a wrong turn. Think about under what situations would this most likely happen. Then create a system to better direct users. You can base your advancements on existing GPS.
    • You are going on vacation for a month and can’t find anyone to water your plants while you’re gone. You need a device that will give your plants the right amount of water – not too much and not too little.

Students will:

  1. Choose a problem.
  2. Do some research.
  3. Brainstorm ways to solve the problem and List several possible solutions.
  4. Choose one idea and draw a detailed picture of the solution.
  5. Explain the solution to class.
Evaluate

Students can be assessed by their designs and their contributions in class discussion.

Lesson 2: How Do I Engineer a Prototype?

What Updates Should I Consider?

Materials

Group Size

2-3 students

Suggested Time

40-60 minutes

Background

It is a long journey from starting to design a product to being ready for the market. Making a prototype is a key milestone in product development. A prototype is an early sample or model produced before the final product exists. It allows engineers to identify issues as early as possible within the development stage and before going to the manufacturing stage. A prototype provides a way for new ideas to be tested, evaluated, and then employed to improve a design. Most engineers test their prototypes over and over again. Generally, there are fundamental differences between a prototype and the final product. Prototypes may be made from different materials or manufactured in a different way compared to the final product. That’s because the final products are usually produced in a very large quantity which requires a very complex manufacturing process involving machines that are not available in the development process. For example, a common way to produce plastic parts is using injection molding, which requires molds that sometimes cost the same as a house. So in the development cycle, engineers use 3D printing to prototype the product, which is very fast and way cheaper. Prototypes are essential tools for design optimization before mass production: they are like scratch paper to mathematicians when contemplating the correct formula for the solution.

Learning Objectives 

Students will be able to:

  • Describe the role of a prototype and its difference from a real product
  • Recognize and explain the limitations of a device based on its intended purposes
  • Determine appropriate constraints for solutions and evaluate the solutions

Standards Alignment

NGSS: HS-ETS1-3: Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics as well as possible social, cultural, and environmental impacts.

  • Science and Engineering Practices: Constructing Explanations and Designing Solutions: Evaluate a solution to a complex real-world problem, based on scientific knowledge, student-generated sources of evidence, prioritized criteria, and tradeoff considerations.
  • Disciplinary Core Ideas: ETS1.B: Developing Possible Solutions: When evaluating solutions, it is important to take into account a range of constraints, including cost, safety, reliability, and aesthetics, and to consider social, cultural, and environmental impacts.
  • Crosscutting Concepts: Influence of Science, Engineering, and Technology on Society and the Natural World: New technologies can have deep impacts on society and the environment, including some that were not anticipated. Analysis of costs and benefits is a critical aspect of decisions about technology.

Basic Outline

Engage (Slides 3-8)
  1. Review the engineering design process and then ask students what the purpose of a prototype is for engineers. Tell students that the prototype allows engineers to evaluate their design before it is made widely available to the public. Students may be familiar with the alpha or beta-testing of video games and programs as an example of prototypes. Having a prototype allows engineers to make decisions about what materials to use, how to fix any design flaws, and whether any improvements can be made.
  2. Ask students how a prototype is different from the finished product. Tell students that the creation of prototypes will differ from creation of the final product in some fundamental ways such as material, process, and verification.
  3. Ask students how the designs of the Robotic Hand created by engineers simulate the movements of a human hand. Remind students that the Robotic Hand is structurally similar to a human hand, and the parts of the Robotic Hand are designed to function similarly to the corresponding parts of a human hand.
  4. Remind students that the Robotic Hand uses the same basic technology as BrainCo’s prosthetic hand, but that the functionality of the Robotic Hand is not the same as the prosthetic hand. For this reason, the Robotic Hand could be seen as a prototype for a prosthetic of the students’ design.
Explore, Part 1 (Slides 9-12)
  1. Explain to the students that during this lab, they will be working as engineers who are deciding what design updates to make to their “prototype prosthetic” (a.k.a. the Robotic Hand) by testing the prototype’s capabilities and deciding what design flaws or improvements could be made to improve the user’s quality of life.
  2. Ask students to consider their everyday activities that they use their hands for and record these activities in the table of the Lab Notes Handout; and then to note which of these activities the “prosthetic prototype” would and would not be able to perform.
  3. Ask students to operate the Robotic Hand and determine its limitations as a “prosthetic prototype”. Then, have the whole class discussion.

Students may note that the Robotic Hand:

    • is unable to feel temperature, so a user may not know they are holding something very hot.
    • cannot determine pressure applied to objects, so a user may break things.
    • cannot abduct (spread sideways) the fingers, so a user would not be able to play the piano.
    • cannot extend (pull open) the fingers, so a user would not be able to quickly release an object.
    • is left-handed, so a user needing a right hand prosthetic would not be able to use it.
    • has smooth surfaces, so a user may not be able to grip smooth or slippery objects.
    • is made of plastic, so a user will not be able to activate touch screens.
    • does not have an opposable thumb, so a user would not be able to play a video game with analog thumb sticks or give a thumbs-up.
Explore, Part 2 (Slides 13-14)
  1. Ask students to:
    Determine the constraints that any solutions for the design should abide by.
    Record these constraints in the Lab Notes Handout.

     

    • Students should include:
      • added cost of materials and sensors.
      • added weight of the prosthetic.
      • availability of materials or parts.
      • difficulty to assemble based on their own experiences from assembling the Robotic Hand.
      • additional time needed to assemble based on their own experiences from assembling the Robotic Hand.
  2. Have the students share their constraints on the “prototype prosthetic.” Compile these lists into a single list for the class. Based on the list of constraints, have the students discuss:
    • Why is each constraint important?
    • What would these constraints mean for the design solutions for the robotic hand?
Explain (Slides 15-17)
  1. After the discussion, remind the students that a good engineer will seek to make a device as useful for the user as possible. To do this, first the engineer must decide what are the most important tasks their device will be able to do. A good engineer will also take into account the constraints of a project before starting to work on the project.
  2. Show students more examples to illustrate the engineering prototypes.
Elaborate

Ask the students to complete the Lab Notes Handout. This can be completed as a homework assignment.

Evaluate

Students can be assessed by their homework or their contributions in class discussion.

Lesson 3: Introduction to 3D Printing

3D Printing Make Anything You Want

Materials

Group Size

2-3 students

Suggested Time

40-60 minutes

Background  

3D printing technology is also known as additive manufacturing. It was originally introduced in the 1980s as a method to quickly and cheaply produced near net shape parts, otherwise known as looks-like prototypes. It’s risen to global prominence in the last decade as machines have become more affordable, accessible, reliable, and more materials have become available.

3D printing is a process of making three dimensional solid objects from a digital file. The creation of a 3D printed object is achieved using additive processes. In an additive process, an object is created by laying down successive layers of material until the object is created. 3D printing is the opposite of subtractive manufacturing which is cutting out a piece of metal or plastic with for instance a milling machine.

In recent years, as a versatile option for manufacturing, 3D printing has rapidly evolved to not only print various polymers but also metals, ceramics, paper, biomaterials, etc., making 3D printing a versatile option for manufacturing. 3D printing has developed significantly in many applications such as manufacturing, medicine, architecture, custom art, and design. More information about 3D printing will be introduced in this lesson.

Learning Objectives

Students will be able to:

  • Recognize the principle and applications of 3D printing
  • Investigate new trends and future possibilities of 3D printing
  • Describe the benefits and limitations of 3D printing

Standards Alignment

NGSS: HS-ETS1-1: Analyze a major global challenge to specify qualitative and quantitative criteria and constraints for solutions that account for societal needs and wants.

  • Science and Engineering Practices: Asking Questions and Defining Problems: Analyze complex real-world problems by specifying criteria and constraints for successful solutions.
  • Disciplinary Core Ideas: ETS1.A: Defining and Delimiting Engineering Problems:
    – Criteria and constraints also include satisfying any requirements set by society, such as taking issues of risk mitigation into account, and they should be quantified to the extent possible and stated in such a way that one can tell if a given design meets them.
    – Humanity faces major global challenges today, such as the need for supplies of clean water and food or for energy sources that minimize pollution, which can be addressed through engineering. These global challenges also may have manifestations in local communities.
  • Crosscutting Concepts: Influence of Science, Engineering, and Technology on Society and the Natural World: New technologies can have deep impacts on society and the environment, including some that were not anticipated. Analysis of costs and benefits is a critical aspect of decisions about technology.

CCSS: ELA-LITERACY.WHST.9-12.8: Gather relevant information from multiple authoritative print and digital sources, using advanced searches effectively; assess the usefulness of each source in answering the research question; integrate information into the text selectively to maintain the flow of ideas, avoiding plagiarism and following a standard format for citation.

Basic Outline

Engage (Slides 3-21)
  1. Class Discussion:
    • What do you know about 3D printing?
    • Can you talk about the difference between a 3D printer and a regular printer?
    • Do you know how the 3D printer works?
  2. Explain to students what 3D printing is and how it works (Slides 5-11).
  3. Tell students that now smaller consumer-friendly 3D printers are bringing additive manufacturing to home and businesses. Show students some designs using small 3D printers (Slides 12-13).
  4. Take the Robotic Hand as an example. Show students some pictures and videos to explain how 3D printer works (Slides 14-20).
    • Here’s a simplified version of how the engineers create, test and manufacture the Robotic Hand:
      • First, the engineers use a CAD software to design the part. Then the engineers assemble individual parts in the computer to see how they fit.
      • Once the engineers think it fits the requirement, they put it into a software and transfer to a language that’s readable by 3D printers. Then the engineers print out the parts to see them in the real world.
      • Finally the engineers forward these design files to factories and produce them in large quantities. The material that the Robotic Hand uses is plastic.
  5. Introduce the materials in 3D printing. Tell students that the most common material used in 3D printing is plastic. Metals, concrete, ceramics, paper, biomaterials, and even food also can be used in 3D printing. These varieties of different material types are also supplied in different states such as powder, filament, pellets, granules, and resin. The use of different materials allows for the creation of some pretty amazing products beyond simple tools and toys (Slide 21).
Explore (Slide 22)

Ask students to investigate new trends and future possibilities of 3D printing. Students will work in pairs or small groups to choose a topic regarding 3D printing and conduct a simple research on the topic.

Explain (Slides 23-28)
  1. Each group will take turns to present their findings to the class.
  2. According to the needs of teaching, play some videos or show more pictures to illustrate 3D printing applications. Explain to students that the possibilities of 3D printers are endless. There are many different shapes and sizes of 3D printers. You can print houses, complex bridges, prosthetics, etc. You can also use a 3D printer to print another 3D printer. In the medical world, doctors are testing bio-materials for regenerative medicine. By using a patient’s cells, doctors could 3D print small body parts like ears and noses. Some surgeons have even tested 3D printed organs for transplants.
Elaborate (Slides 29-32)

Ask students to discuss in a smaller group first, then have the whole class discussion.

  • Based on what you’ve learned about 3D printing, what are the benefits and limitations of 3D printing?
  • 3D Printers are becoming more and more widespread in our everyday lives. Could you talk about how 3D printers make a positive impact on our society?

Here are some points that may help:

   Benefits & Value

  • Customisation    
  • Complexity
  • Tool-less
  • Sustainable / Environmentally Friendly
  • Efficient Prototyping

   Limitations 

  • Speed of Large Production Runs
  • Cost of Large Production Runs
  • Materials
  • Accuracy
Evaluate

Students can be assessed by their presentation or their contributions in class discussion.

Lesson 4: Introduction to Circuits and PCBs

What Controls the Fingers of a Robotic Hand?

Materials

Group Size

2-3 students

Suggested Time

40-60 minutes

Background

An electric circuit works by providing a closed-loop to allow current to flow through a system. In its most simple form, an electrical circuit consists of three fundamental parts: a source of electrical energy, a load that has electrical resistance, and conductors to connect the source to the load. A circuit often includes other components such as switches, resistors, capacitors, fuses, etc. There are two common types of electric circuits: series circuit and parallel circuit. In a series circuit, there is only one path for the electrons to flow. In a parallel circuit, the different parts of the electric circuit are on several different branches.

IR sensors are generally used for designing remote control technology. The IR remote sends infrared signals, and then the IR receiver receives the signals and sends them to a control circuit inside the device after decoding them. The controller will then perform the necessary action. Servo motors are self-contained electrical devices that output motion under closed-loop control, allowing for precise control of angular position. The Servo motor comprises of three wire system known as Power, Ground, and Signal. Arduino Uno is an open-source microcontroller board, and anyone can modify and optimize the boards for better functionality. Programs can be loaded on to it from the easy-to-use Arduino computer program (Arduino IDE).

Learning Objectives

Students will be able to:

  • Identify the electronic components (servo motors, IR sensors, Arduino Uno, etc.) and understand their functions
  • Draw the basic electric circuit diagram of the control box of the Robotic Hand

Standards Alignment

NGSS: HS-PS3-3: Design, build, and refine a device that works within given constraints to convert one form of energy into another form of energy.

  • Science and Engineering Practices: Constructing Explanations and Designing Solutions: Design, evaluate, and/or refine a solution to a complex real-world problem, based on scientific knowledge, student-generated sources of evidence, prioritized criteria, and tradeoff considerations.
  • Disciplinary Core Ideas:
    – PS3.A: Definitions of Energy: At the macroscopic scale, energy manifests itself in multiple ways, such as in motion, sound, light, and thermal energy.
    – PS3.D: Energy in Chemical Processes: Although energy cannot be destroyed, it can be converted to less useful forms—for example, to thermal energy in the surrounding environment.
    – ETS1.A: Defining and Delimiting Engineering Problems: Criteria and constraints also include satisfying any requirements set by society, such as taking issues of risk mitigation into account, and they should be quantified to the extent possible and stated in such a way that one can tell if a given design meets them.
  • Crosscutting Concepts: Energy and Matter: Changes of energy and matter in a system can be described in terms of energy and matter flows into, out of, and within that system.

CCSS: ELA-LITERACY.RST.9-12.4: Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific or technical context relevant to grades 9-12 texts and topics.

Basic Outline

Engage (Slides 3-13)
  1. Discuss with students the fundamentals of an electrical circuit. Tell students that in the most simple form, an electrical circuit consists of three fundamental parts, including a power source, a conductor, and a load. A circuit often includes other components such as switches, resistors, capacitors, fuses, etc.
  2. Guide students to recall the two basic types of electrical circuits: series circuit and parallel circuit. In a series circuit, all components are connected end-to-end, forming a single path for current flow. In a parallel circuit, all components are connected across each other, forming exactly two sets of electrically common points. A combination circuit involves the dual use of series and parallel connections in a circuit. Show students examples to illustrate the common types of connections made in electric circuits.
  3. Introduce students to the essential electronic components in the Robotic Hand.
    • Servo Motor: Servo motors are most commonly used in closed-loop systems. It is a self-contained electrical device that rotates parts of a machine with high efficiency and with great precision. A servo motor has three wires: power, ground, and signal. The power wire is typically red (GND, battery negative terminal); the ground wire is typically black or brown (Vservo, battery positive terminal); the signal pin is typically yellow, orange, or white (servo control signal line). Servos come in many sizes and types. The Robotic Hand uses SG90 micro servo, which is small, cheap, and easy to connect.
    • IR Sensor: Infrared technology addresses a wide variety of wireless applications. IR sensors are generally used for designing remote control technology. The IR remote is based on the principle of using infrared light as the medium of communication. A simple IR remote is also called an IR transmitter, which looks like a regular LED but emits Infrared Light. An IR receiver is an electronic device that receives information from an IR remote, decodes the signal, and sends it to another device like a Microcontroller (e.g., Arduino UNO). TSOP1738, a very common and popular IR receiver, is used in the Robotic Hand. It consists of three pins namely: power, ground, and output. The demodulated output of the TSOP1738 IR receiver can be directly decoded by a microcontroller.
    • Arduino Uno: Microcontrollers are widely used in embedded systems and make devices work according to our needs and requirements. There are many versions of Arduino boards introduced in the market. Arduino Uno is the most popular electronic platform for interactive projects and prototypes. Arduino Uno is a microcontroller board developed by arduino.cc and based on the Microchip Atmega328. It is an open-source platform, which means the boards and software are readily available and anyone can modify and optimize the boards for better functionality. Arduino UNO is programmed via type B USB connector mounted on board.
Explore (Slide 14)

Students will draw a block diagram to illustrate the relationship between the battery, servo motors, a controller (UNO Board), and IR sensor in an electric circuit.

Explain (Slides 15-16)

Hold a class discussion and then show students the diagram. Explain to students that the battery supplies electric power to all of the electrical system components. Arduino Uno plays an important role in electric circuits. The UNO board reads inputs—the signal of the IR sensor— and then turns it into an output, activating a motor, so servo motors are able to move according to the button pressed on IR remote.

Elaborate (Slides 17-19)
  1. Ask students to draw a schematic diagram according to the diagram they draw in Activity 1. The presentation of the interconnections between circuit components in the schematic diagram does not necessarily correspond to the physical arrangements in the control box of the Robotic Hand. This activity can be completed as a homework assignment.
  2. Show students the answer to the circuit diagram. Remind students that the circuit diagram they drew is not the actual circuit diagram of the control box. It’s a general circuit diagram; the logic behind the electric circuits is the same but the circuit of the control box of the Robotic Hand is more complicated. For detailed information, they can refer to the Assembly Guide.
Evaluate (Slides 20)
  1. After-class activity: students can build some simple circuits based on their abilities. Here are some examples:
    • Level 1: design a circuit that lights up a LED light bulb.
      Level 2: design a circuit that lights up LED lights with certain blinking patterns.
      Level 3: design a circuit that powers a Servo motor.
      Level 4: design a remote-control system for the Servo using IR sensors.
  2. Students can be assessed by their assignments, their contributions in class discussions, and their ability to follow directions.

Lesson 5: Introduction to Manufacturing

How Are Things Made?

Materials

Group Size

2-3 students

Suggested Time

40-60 minutes

Background  

Humans have been manufacturing things for centuries, from simple tools to complex robots. Manufacturing is the process of converting raw materials into physical goods. Everything we use in our daily lives is made of material or a combination of materials, including metals, ceramics, polymers, semiconductors, and composites. Manufacturing processes include mainly six categories: forming, casting, molding, joining, machining, and additive manufacturing. Each one contains a large number of different manufacturing techniques:

  • Forming: forging, extrusion, rolling
  • Casting: die casting, sand casting, investment casting
  • Molding: injection molding, compression molding, blow molding
  • Joining: welding, soldering, fastening
  • Machining: turning, drilling, reaming
  • Additive: 3D printing, laser sintering, vat photopolymerization

A lot of factors need to be considered when selecting the right manufacturing process such as the material you are working with, the geometry of the object, the number of parts you are producing, the cost of tool and material, and required levels of automation.

Learning Objectives

Students will be able to:

  • Understand a number of different manufacturing techniques and the pros and cons of each technique
  • Evaluate how and why manufacturing has changed over time.

Standards Alignment

NGSS: HS-ETS1-3: Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics as well as possible social, cultural, and environmental impacts.

  • Science and Engineering Practices: Constructing Explanations and Designing Solutions: Evaluate a solution to a complex real-world problem, based on scientific knowledge, student-generated sources of evidence, prioritized criteria, and tradeoff considerations.
  • Disciplinary Core Ideas: ETS1.B: Developing Possible Solutions: When evaluating solutions, it is important to take into account a range of constraints, including cost, safety, reliability, and aesthetics, and to consider social, cultural, and environmental impacts.
  • Crosscutting Concepts: Influence of Science, Engineering, and Technology on Society and the Natural World: New technologies can have deep impacts on society and the environment, including some that were not anticipated. Analysis of costs and benefits is a critical aspect of decisions about technology.

Basic Outline

Engage (Slides 3-30)
  1. Ask students what manufacturing is and then invite students to describe manufacturing. Explain to students that common definitions of manufacturing have five main characteristics, including design and engineering, materials science, process technology, quality, and management. The first characteristic (Design and Engineering) has been introduced in Lesson 1.
  2. Explain to students that everything we use in our daily lives is made of material or a combination of materials. Manufacturers evaluate different kinds of materials to identify their properties and their suitability for different purposes.
  3. Explain to students that there are six main categories of manufacturing processes, which are forming, casting, molding, joining, machining, and additive manufacturing. Each one of these categories contains a large number of different manufacturing techniques. Guide students to look through each of the six categories in detail and give students an overview of the pros and cons of each. More information is available on the slides.
    • Forming involves applying forces or pressure and plastically deforming the material to produce the desired shape. It is typically used for metals. Three common forming processes are forging, extrusion, and rolling.
    • Casting involves pouring molten metal into a mold and allowing it to solidify. Casting is most commonly used for metals. Three common types of casting are die casting, sand casting, and investment casting.
    • Molding involves shaping a liquid or pliable material using a mold. Most of the time molding is used for forming plastics. Typical molding processes are injection molding, compression molding, and blow molding.
    • Machining is a material removal process, where a tool is used to remove material from a larger object. It is often used for secondary shaping. Machining can be used for a wide range of materials, including metals, plastics, and wood. Examples of machining include drilling, turning, and reaming. Much of modern-day machining is carried out by computer numerical control (CNC).
    • Joining involves combining multiple separate components into a larger assembly. Joining is a secondary process. Welding, riveting, brazing, soldering, and fastening are all different types of joining processes.
    • Additive manufacturing involves adding material to build up the desired object, typically one layer at a time. 3D printing, selective laser sintering, and vat polymerization are examples of additive manufacturing techniques.
  4. Ask students what factors designers and engineers should consider when selecting the appropriate manufacturing process. Explain that there are a lot of different factors that need to be considered when selecting the right manufacturing process. This includes material, object geometry, number of parts, tool and material costs, and required levels of automation.
Explore (Slides 31-35)
  1. Show students some media reports and ask them to explore “The Manufacturing Journey of iPhone”.
    • Video: iPhone Manufacturing process in Factory
    • Article: How&Where iPhone is made
  2. Think:
    • What are the differences between these iPhones?
    • Why do you think these changes were made?
    • What factors have influenced these changes?
Explain (Slide 36)

Explain to students that manufacturing changes in production and engineering over time based on changes in society, engineering, and technology. The assembly line is important during this time due to its purpose in mass production. The whole point of an assembly line is that the parts or processes for a product are completed in a sequence by individual workers. No single worker is responsible for the entire finished product. Each worker or machine does one part and then the parts are put together to make the finished object. With this approach, the product is made much more quickly and efficiently.

Elaborate (Slide 37)
  1. Ask students what manufacturing looks like today.
  2. After students share their ideas, explain to them that these days assembly lines are made up of robots and machines. A person is only necessary to either oversee the whole thing or make sure the product is put together correctly at the end. The use of machines has changed everything. Manufacturers no longer need as many skilled workers to put products together; instead, they need people who understand technology to program and troubleshoot the computers and machines that do all the heavy lifting. These computer experts have replaced the skilled workers who used to work on the assembly line.
Evaluate
  1. Ask students to summarize what they learned about manufacturing and record the conclusions in their Lab Notes handout. This can be completed as a homework assignment.
  2. Students can also be assessed by their contributions in class discussion.

Lesson 6: Documentation Project

Design a Prosthetic Hand

Materials

Group Size

2-3 students

Suggested Time

40-60 minutes

Background  

Product design consists of many components. An engineer starts with recognizing proper design questions regarding the designated functionality of the device. Then, the engineer gathers the required knowledge and formulate solutions to these questions. Some key information to keep in consideration includes materials, aesthetics, ergonomics, sustainability, etc. Simultaneously, the engineer may also perform market research. Always remind oneself with these questions: what’s the significance of the product and who are the potential users. Involving users’ needs in the designing process helps an engineer to better design the appearance and the reliability of the product, which would improve the user experience. Finally, one shall always estimate the cost of the product and keep track of the budget.

Equally critical is the documentation of the thought and work process of designing. This not only serves for demonstrating purposes but also helps for any further adjustment for the product. Engineers need to constantly review the device’s functionality and analyze the advantages and disadvantages of the product. Appropriate documentation of one’s work provides a foundation for future improvements.

Learning Objectives

Students will be able to:

  • Apply an understanding of the engineering design process to design a prosthetic hand
  • Present a written design report and an oral design presentation

Standards Alignment

NGSS:

HS-ETS1-2: Design a solution to a complex real-world problem by breaking it down into smaller, more manageable problems that can be solved through engineering.

  • Science and Engineering Practices: Constructing Explanations and Designing Solutions: Design a solution to a complex real-world problem, based on scientific knowledge, student-generated sources of evidence, prioritized criteria, and tradeoff considerations.
  • Disciplinary Core Ideas: ETS1.C: Optimizing the Design Solution: Criteria may need to be broken down into simpler ones that can be approached systematically, and decisions about the priority of certain criteria over others (trade-offs) may be needed.

HS-ETS1-3: Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics as well as possible social, cultural, and environmental impacts.

  • Science and Engineering Practices: Constructing Explanations and Designing Solutions: Evaluate a solution to a complex real-world problem, based on scientific knowledge, student-generated sources of evidence, prioritized criteria, and tradeoff considerations.
  • Disciplinary Core Ideas: ETS1.B: Developing Possible Solutions: When evaluating solutions, it is important to take into account a range of constraints, including cost, safety, reliability, and aesthetics, and to consider social, cultural, and environmental impacts.
  • Crosscutting Concepts: Influence of Science, Engineering, and Technology on Society and the Natural World: New technologies can have deep impacts on society and the environment, including some that were not anticipated. Analysis of costs and benefits is a critical aspect of decisions about technology.

CCSS: ELA-LITERACY.WHST.9-12.7: Conduct short as well as more sustained research projects to answer a question (including a self-generated question) or solve a problem; narrow or broaden the inquiry when appropriate; synthesize multiple sources on the subject, demonstrating understanding of the subject under investigation.

Basic Outline

Engage (Slides 3-4)
  1. Explain to students that smart engineering decisions are based on research on anticipating user, societal and technological trends. A proactive engineer creates products and systems that are appropriate, effective, fail-resistant, and economically successful.
  2. Tell students that during this class they will put the engineering design process into practice by designing their own version of a prosthetic hand. Students will work collaboratively to complete a design project. Each group is required to make a public oral presentation during the class and submit a written design report at the end of the class.
Explore (Slide 5)
  1. Students will identify a problem that needs to be solved and use the “Product Design Checklist” to clarify directions for their designs.
  2. Students will design the prosthetic hand individually. Then, group members will evaluate each other’s design to determine which one to build. Depending on student ability levels, teachers can decide whether students build the prototype.
Explain/Presentation (Slide 6)

Each group will make a public oral presentation to explain their designs.

Elaborate/Review (Slide 7)
  1. Ask students to display their designs around the room and leave a copy of the Gallery Walk Feedback Form with their project. Students will walk around to the other groups’ designs and provide commendations and considerations.
  2. Students will use the Gallery Walk Feedback Form and think about what further work would need to be done.
Evaluate (Slide 8)
  1. Each group is required to submit a written design report. Students can be evaluated on their reports. This report can include, but not limited to:
    • Final design: What does it look like? How does it work? Product features?
    • Target Market
    • Engineer Details: Materials Choice, Mechanism, Cost, Tech, etc.
  2. A simple Design Rubric is provided.