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來自 University of California San Diego 的課程

Internet of Things: Sensing and Actuation From Devices

88 個評分

University of California San Diego

Internet of Things: Sensing and Actuation From Devices

88 個評分

Have you wondered how information from physical devices in the real world gets communicated to Smartphone processors? Do you want to make informed design decisions about sampling frequencies and bit-width requirements for various kinds of sensors? Do you want to gain expertise to affect the real world with actuators such as stepper motors, LEDs and generate notifications? In this course, you will learn to interface common sensors and actuators to the DragonBoard™ 410c hardware. You will then develop software to acquire sensory data, process the data and actuate stepper motors, LEDs, etc. for use in mobile-enabled products. Along the way, you’ll learn to apply both analog-to-digital and digital-to-analog conversion concepts. Learning Goals: After completing this course, you will be able to: 1. Estimate sampling frequency and bit-width required for different sensors. 2. Program GPIOs (general purpose input/output pins) to enable communication between the DragonBoard 410c and common sensors. 3. Write data acquisition code for sensors such as passive and active infrared (IR) sensors, microphones, cameras, GPS, accelerometers, ultrasonic sensors, etc. 4. Write applications that process sensor data and take specific actions, such as stepper motors, LED matrices for digital signage and gaming, etc.

從本節課中

Terminology/Cheat Sheet (Beginner)

In this course, you will see a lot of new words and acronyms you might not be familiar with. If you feel comfortable with your knowledge of tech terminology, feel free to skip these lessons since they will not affect the overall integrity of the course. If you see something that you want to know a little more about, feel free to watch the video to gain insight on some basic concepts. We do expect you to know the majority of this material before going into the next module, we would recommend going through the lessons as a quick brush up.

Introduction to Lesson 31:04

Breadboards5:52

A look back at Lesson 31:02

與講師見面

Ganz Chockalingam
Principal Engineer
Qualcomm Institute of Calit2, UC, San Diego
Harinath Garudadri
Associate Research Scientist
Qualcomm Institute of Calit2, UC, San Diego

Hey everyone.

Let's go ahead and get started with the supplemental material.

So the first thing we have on our place is Java,

which is a language we'll be using for Android development.

>> And so the first key feature about Java that always sticks out,

is it's object oriented.

And Object Oriented is a very revolutionary idea that makes every

programmer's life easier.

And, basically object oriented is centered around object as the name implies.

What is an object?

>> An object is basically, it's as the word implies in real life also,

it does something or it has a certain behavior.

So, in programming you're gonna have many different behaviors.

You're gonna wanna do many different things.

So you can just make an object for

each behavior you wanna do and encapsulate that.

>> So, what's object oriented programming?

All right, so with object-oriented programming we have certain advantages,

disadvantages.

We have code reuse and recycling, which means you can make one set of code and

apply it to many different uses.

We have encapsulation, which is basically privacy.

So, if you have one set of code, and if you have another set of code later on, and

if they're both interacting with each other,

you can control what one program knows about the other program.

Both programs are not completely vulnerable to the other.

And lastly, we have design benefits.

So, the first two points are basically things that combine to give

Java lots of flexibility and design benefits.

So, right there.

So, right there we have an example.

So, let's say we make an object called animal.

It's an animal class.

And then we're gonna have three other objects.

We're gonna have a dog, a cat and a parrot.

Now, both the dog and the cat, they're gonna have an age and

they're gonna have a size.

So instead of having separate implementations of age and

size inside a dog and a cat.

We can just have those implementations in animal.

And then inherit it into a dog and a cat.

>> This is because maybe you realize something, and

you had to change something for the age.

Age functions or whatever.

You'd have to go in every single, you'd have to go through the cat,

the dog to make all the changes.

But now you can just change the animals and it's changed for everything.

>> That's a very good point.

So if you have something that goes up to 100 different objects and

large scale programs.

You will have to do many different objects.

So by inheritance, you can just change one thing and it'll apply to all the others.

And second thing, when I said encapsulation, so

I talked about privacy there.

And basically what privacy is that a dog and

a cat that are raised similar in many ways but they are also different.

A dog is a canine and a cat is a feline.

So they're gonna have some functionalities that are different.

So although they can inherit a lot of the same functionalities,

a dog is gonna have certain functionalities that are different.

And so a cat doesn't need to know about what a dog can do.

And a dog doesn't need to know about what a cat can do.

So encapsulation basically allows data hiding and you can keep everything very

separate, very concise and that's what encapsulation does.

However the disadvantages of all this is that

>> We have large sizes because maybe

you'll end up with kind of an inheritance.

You'll have the cat having things from animal, and

maybe things from other things

>> Right >> And what not.

>> So it can make your program slower at times and such.

>> And Java's also an interpreted language, which means

it needs to go through an interpreter to change your language into more of

>> Compile code, machine code [CROSSTALK]

>> For assembler and whatnot.

Tends to lead to story programs as compared to say assembly.

>> Right exactly.

>> Oh yeah.

This is also covered more in depth in the page documents as well as

the previous course.

Course 2, module 1.

>> We go over these things more in detail in day two.

>> Yeah, where we go over the concept of object oriented programming.

Okay, so let's talk more about Java.

>> And so, Java can be, like Randy said in the very opening, it can be applied for

Android development >> So as we went over in the previous

course, we're gonna be using SDK, you're gonna be using Android Studio a lot.

Android Studio's completely run on Java.

And all your Android phones actually run on Java,

so that's one very good thing about Java.

>> And there's tons of libraries available.

You can look up anything.

There's a ton of documentation too.

So if you didn't know how say, a string worked in Java, you just type into Google,

type in String, Java, and it'll come up with some documentation,

tell you how you use it, what other functions or methods that are possible.

>> And it's a very common language,

so the more familiar you are with it, the better it's going to be.

>> Yeah, there's tons of resources out there, so look around, check out

documents, check out the previous course's >> [CROSSTALK].

Awesome.

And then we'll see you guys next time.

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