Ribs increase the bending stiffness of a part. Without ribs, the thickness has to be increased to increase the bending stiffness. Adding ribs increases the moment of inertia, which increases the bending stiffness. Bending stiffness = E (Young's Modulus) x I (Moment of Inertia)
The rib thickness should be less than the wall thickness-to keep sinking to a minimum. The thickness ranges from 40 to 60 % of the material thickness. In addition, the rib should be attached to the base with generous radiusing at the corners.
At rib intersections, the resulting thickness will be more than the thickness of each individual rib. Coring or some other means of removing material should be used to thin down the walls to avoid excessive sinking on the opposite side.
The height of the rib should be limited to less than 3 x thickness. It is better to have multiple ribs to increase the bending stiffness than one high rib.
The rib orientation is based on providing maximum bending stiffness. Depending on orientation of the bending load, with respect to the part geometry, ribs oriented one way increase stiffness. If oriented the wrong way there is no increase in stiffness.
Draft angles for ribs should be minimum of 0.25 to 0.5 degree of draft per side.If the surface is textured, additional 1.0 degree draft per 0.025 mm (0.001 inch) depth of texture should be provided.
Living hinges are thin sections of plastic that connect two segments of a part to keep them together and allow the part to be opened and closed. Typically these are used in containers that are used in high volume applications such as toolboxes, fish tackle boxes, CD boxes etc.
The materials used to make a living hinge are usually a very flexible plastic such as polypropylene and polyethylene. These can flex more than a million cycles without failure.
Besides meeting the design guidelines, the hinges have to be processed properly. The molecules have to be oriented along the hinge line for the hinge to have acceptable life.
As molded the fibers of the plastic are somewhat random in orientation. In order to orient the fibers to aid in prolonging the hinge life, some or all of the following practices should be followed:
The gate location should be such as to allow the plastic to flow across the hinge for maximum strength.
As the part comes out of the mold, it needs to be flexed a minimum of 2 times while it is still hot, for optimum strength
Coining is often done to give the hinge, enhanced properties. The coining process compresses the hinge to a pre-determined thickness. The strain induced is greater than the yield stress of the plastic. This will plastically deform the hinge (i.e. place it outside the elastic range into the plastic range). The amount of coining (compression) should be less than the ultimate stress, to keep the hinge from fracturing.
The finished thickness after coining should be from 0.25 to 0.5 mm (0.010 to 0.020 inch). This keeps the stress in the outer fibers from exceeding the yield strength when being flexed.This process can also be done by heating the hinge or the coining tool to a temperature below the glass transition tempertature of the plastic. This allows for easier coining and somewhat enhanced properties, as the plastic "flow" easier when being heated.
What is your project named? my-app Would you like to use TypeScript? No / Yes Would you like to use ESLint? No / Yes Would you like to use Tailwind CSS? No / Yes Would you like to use `src/` directory? No / Yes Would you like to use App Router? (recommended) No / Yes Would you like to customize the default import alias (@/*)? No / Yes What import alias would you like configured? @/*
아두이노 Uno, Mega2560 등의 보드에 꽂아서 사용하는 컬러 터치 LCD입니다. 동봉된 터치펜으로 손가락보다 정밀한 입력도 가능하며 예제 소스코드로 손쉽게 구동할 수 있습니다. MicroSD카드소켓이 있어 저장된 이미지 또는 데이터를 표시하는 등의 응용이 가능합니다. 추가 reset버튼이있어 기존 버튼을 가리더라도 불편이 없습니다. ※아두이노보드가 포함되어있지 않은 제품입니다.
화면크기 : 48.96mm×36.72mm(2.4inch) 전체크기 : 72.20mm×52.70mm 해상도 : 320×240 pixel (QVGA) 지원색상 : RGB 지원보드 : Arduino Uno Arduino Due Arduino Mega2560 Arduino Mega ADK Arduino Leonardo 드라이버IC : ILI9341 화면 인터페이스 : 8bit parallel data bus 외부 인터페이스 : microSD 소켓 구성품 : TFT LCD 쉴드, 터치펜
This project uses on off-the-shelf capacitive touch shield or module to provide touch-sensitive pads for a 12 (recommended for beginners) to 48 (advanced) note “piano”.
These are the key Arduino tutorials for the main concepts used in this project:
As you can see one is a shield for the Arduino Uno with crocodile clip friendly connections. The other is a generic breakout board with headers for using with a solderless breadboard and any microcontroller of your choice.
For an alternative, if you search for MPR121 on popular auction sites or Chinese suppliers you will find a number of breakout boards that look very similar to the now discontinuedSparkfun Capacitive Touch Sensor Breakoutboard, again designed for use with solderless breadboards and any microcontroller you fancy. The one I found looks like this:
I have an Adafruit shield and several cheap ebay modules, so I’m basing the rest of this project around those.
Using a Single Module – 12 Inputs
By the far the simplest thing is to use one of these modules to provide 12 inputs. In the case of the Adafruit shield, just plug in the shield and you are ready to go!
In the case of the non-Adafruit modules, the following connections are required:
Arduino 3.3V --- 3.3V or VIN
Arduino GND --- GND
Arduino SDA or A4 --- SDA
Arduino SCL or A5 --- SCL
One key feature worth noting is that the MPR121 chip itself is a 3.3V device not 5V. The Adafruit boards include an on-board regulator which happily takes care of the power conversion. The non-Adafruit devices do not, they have to be powered from the 3.3V supply of the Arduino or you will damage the boards.
Now all the circuits and tutorials I’ve seen imply that as long as you power the module from the 3.3V pin of the Arduino, then you can link up SDA and SCL to the Arduino and it just works. But this means that you are using 5V logic at the Arduino end to talk to 3.3V logic at the MPR121 end. This might be ok – the MPR121 datasheet wasn’t very illuminating on the topic. In practice this does seem to work, but I don’t know for how long.
Extending to Multiple Modules – up to 48 Inputs
All of these modules use one of the built-in communication busses of the Arduino for communications – in this case the I2C interface (which stands for Inter-Integrated Circuit) which is a serial protocol using a data signal (SDA), a clock (SCL), power and ground. I’ll not go into the details of how I2C works here, but it is worth noting that every device connected to I2C has an address to uniquely identify it to the Arduino.
All of these boards allow you to choose one of four addresses. By default, its address is 0x5A (that is 5A in hexadecimal). By linking the ADDR (or ADD) pin to one of 3.3V, SDA or SCL it is possible to change the default and choose 0x5B, 0x5C or 0x5D. This means a single microcontroller than support up to 48 capacitive touch inputs using these modules.
I have to say, the Adafruit modules are very simple to change address – just patch the ADDR pin to one of 3.3V, SDA or SCL, or leave it unconnected (it is linked to GND by default). The Sparkfun based boards are more complication in that they need you to cut a track between a jumper that will default to connecting ADD(R) to ground or you risk shorting the board.
At the very least, I found that the address selection using SDA or SCL doesn’t work when using 5V levels.
The solution, if you are using one of these boards with no on-board regulator, is to use a bi-directional level shifter that takes 5V on one side and converts it to 3.3V on the other. This can be used for the SDA/SCL signal pins. Mine looks like this.
IMPORTANT: Recall that there is a jumper that has to be cut to allow ADDR to be linked to another pin for second and subsequent boards. For my module, this is on the underside as shown here.
To resort back to the default setting, the link between ADDR and GND must be re-established either by a solder joint here or linking the external pin to GND.
The final circuit for me, supporting several of these MPR121 breakout boards looks like this.
In summary, the Adafruit modules are much easier to use, in fact the shield is very easy to setup! The Adafruit module is easier if you plan to use several modules linked together, but the non-Adafruit modules can be made to work ok and can be found very cheaply online if you look.
The Code
Regardless of which module you chose, Adafruit have provided an Arduino library for the MPR121 which works really well with any module based around the MPR121 chip. You need to install it using the library manager – just search for MPR121 and you’ll see “Adafruit_MPR121”. The provided example code is a quick way to test that your module is working using simple “one-module” connections as described above.
I have taken the basic code from the Arduino Touch Pianoand updated it to use the Adafruit library.
Now, I want to support up to four of these modules, which will therefore support up to 48 capacitive inputs – that is enough for four octaves! So I’ve used the ToneMelody pitches.h file once again to define frequencies for the Arduino tone() function for the range C3 up to B6.
The Adafruit library links up to the MPR121 using a Adafruit_MPR121 programming object, so to support four devices I include four of these objects (called cap1 to cap4).
// It is possible to have up to four of these connected.
// But it needs the "addresses" to be set correctly.
Adafruit_MPR121 cap1 = Adafruit_MPR121();
Adafruit_MPR121 cap2 = Adafruit_MPR121();
Adafruit_MPR121 cap3 = Adafruit_MPR121();
Adafruit_MPR121 cap4 = Adafruit_MPR121();
In the code I look for devices at each of the four I2C bus addresses (0x5A, 0x5B, 0x5C, 0x5D) and record any I find using the “numcaps” variable. Note that I actually use the lowest four bits to record which modules are found, so the first module (at 0x5A) is indicated by the lowest bit (i.e. numcaps = 1) and the others by bits 2, 3 and 4 (or values of 2, 4, and 8 respectively). This means I am able to work out which of the boards are present later in the code by examining the bits of numcaps.
Then in the main loop() function I scan any found devices (by examining the bits of numcaps) and read the 12 inputs for each one.
// Loop through all possible cap devices
for (int c=0; c<4; c++) {
// Get the currently touched pads for all found cap devices
uint16_t currtouched;
if (numcaps & (1<<c)) {
switch (c) {
case 0:
currtouched = cap1.touched(); break;
case 1:
currtouched = cap2.touched(); break;
case 2:
currtouched = cap3.touched(); break;
case 3:
currtouched = cap4.touched(); break;
}
...
I then use this as the basis for which note to play via the tone() function. The code will always “play” the highest note detected and will keep playing until either the note changes or no notes are detected.
If you turn on the Arduino serial monitor, there is a continual feed of debug output that tells you which sensors have been read at any one time which can be handy for fault finding.
The standard 220Ω resistor-to-speaker circuit is added from pin 12 and GND for the audio output to complete the module.
These modules make it relative easily to do a “diy” version of theInstant Touch Music. With a bit of work it can be seen that many more inputs are possible. These modules certainly take much of the complication of capacitive sensing away from the code compared todoing it all by hand.
Now that I’ve introduced the idea of communicating with off the shelf modules using one of the built-in IO busses from the Arduino, there are many more modules that have musical potential that could be looked at.
실행 중인 편집기를 닫고 패치의 압축을 푼 다음 HMIFORM.dll 및 hmitype.dll 두 파일을 Windows 폴더 "Program Files (x86)\USART HMI\"에 복사하고 편집기를 시작합니다.현재 버전에 대한 업데이트를 선택하지 마십시오.패치가 자동으로 적용되며 편집기는 영어로 표시됩니다.링크를 클릭하면 중국어 페이지로 연결될 수 있다는 점에 유의하세요.
- 충전/방전을 반복함으로써 불안정한 전원을 잡아주기 위해 사용 - 직류를 통과시키지 않고 교류만 통과시키게 함 - 다이오드와 정류회로를 구성하여 교류를 직류로 만듬 - 콘덴서의 충전시간을 이용해서 펄스의 시간지연을 만듬 - 저항과 함께 구성하여 여러 신호들 중에서 저주파 또는 고주파 신호만을꺼냄 - 노이즈를 제거하기 위한 방법으로 사용 - IC(집적회로)의 안정된 작동을 위해 사용.
typedef 선언은 typedef를 스토리지 클래스로 사용하는 선언입니다. 선언자는 새 형식이 됩니다. typedef 선언을 사용하여 C에서 이미 정의된 형식이나 사용자가 선언한 형식에 대한 보다 짧거나 의미 있는 이름을 생성할 수 있습니다. typedef 이름을 사용하면 변경될 수 있는 구현 정보를 캡슐화할 수 있습니다.
typedef 선언은 변수 또는 함수 선언과 같은 방식으로 해석되지만, 선언에 형식이 지정되었다고 가정하는 대신 식별자가 형식의 동의어가 됩니다.
What’s the difference between ESP32 and ESP8266? Should you use the ESP32 or the ESP8266 in your projects? In this article, we’ll compare the ESP32 with the ESP8266 and cover the pros and cons of each board.
The ESP32 and ESP8266 are cheap Wi-Fi modules perfectly suited for DIY projects in the Internet of Things (IoT) and Home Automation fields.
Both chips have a 32-bit processor. The ESP32 is a dual-core 160MHz to 240MHz CPU, whereas the ESP8266 is a single-core processor that runs at 80MHz.
These modules come with GPIOs that support various protocols like SPI, I2C, UART, ADC, DAC, and PWM. The best part is that these boards come with wireless networking included, which makes them apart from other microcontrollers like the Arduino. This means that you can easily control and monitor devices remotely via Wi-Fi or Bluetooth (in the case of ESP32) for a very low price.
Alternatively, if you don’t need to use its wireless capabilities, you can use the ESP32/ESP8266 to control inputs and outputs as you would do with an Arduino. However, you should take into account that whereas the Arduino works with 5V logic, the ESP32 and ESP8266 work at 3.3V.
Both boards are cheap, but the ESP32 costs slightly more. While the ESP32 can cost around $6 to $12, the ESP8266 can cost $4 to $6 (but it really depends on where you get them and what model you’re buying).
The following table shows the main differences between the ESP8266 and the ESP32 chips (table adapted from AMICA_IO).
ESP8266ESP32
ESP8266
ESP32
MCU
Xtensa Single-core 32-bit L106
Xtensa Dual-Core 32-bit LX6 with 600 DMIPS
802.11 b/g/n Wi-Fi
HT20
HT40
Bluetooth
X
Bluetooth 4.2 and BLE
Typical Frequency
80 MHz
160 MHz
SRAM
X
✓
Flash
X
✓
GPIO
17
34
Hardware /Software PWM
None / 8 channels
None / 16 channels
SPI/I2C/I2S/UART
2/1/2/2
4/2/2/2
ADC
10-bit
12-bit
CAN
X
✓
Ethernet MAC Interface
X
✓
Touch Sensor
X
✓
Temperature Sensor
X
✓(old versions)
Hall effect sensor
X
✓
Working Temperature
-40ºC to 125ºC
-40ºC to 125ºC
Price
$ (3$ - $6)
$$ ($6 - $12)
Where to buy
Best ESP8266 Wi-Fi Development Boards
ESP32 Development Boards Review and Comparison
Using ESP32 or ESP8266 bare chips is not easy or practical, especially when testing and prototyping. Most of the time, you’ll want to use ESP32 and ESP8266 development boards. These boards come with all the needed circuitry to power the chip, connect it to your computer, a circuit to upload code easily, pins to connect peripherals, built-in power and control LEDs, and other useful features.
The ESP32 and ESP8266 development boards we use more often are the ESP32 DEVKIT DOIT Development board and the ESP8266 ESP-12E NodeMCU Kit and these are the ones we recommend for beginners. However, there are many other models of development boards that you can choose from. We recommend that you read the following guides:
The ESP32 has more GPIOs than the ESP8266, and you can decide which pins are UART, I2C, SPI—you need to set that on the code. This is possible due to the ESP32 chip’s multiplexing feature that allows you to assign multiple functions to the same pin.
If you don’t set them on the code, they will be on the pins defined by default, as shown in the following figure (this is an example for the ESP32 DEVKIT V1 DOIT board (version with 36 GPIOS)—the pin location can change depending on the manufacturer).
To learn more about the ESP32 GPIOs and how to use them, read:
You can set PWM signals in any GPIO with configurable frequencies and duty cycle set on the code.
When it comes to the analog pins, these are static, but the ESP32 supports measurements on 18 channels (analog-enabled pins) versus just one 10-bit ADC pin on the ESP8266. The ESP32 also supports two 8-bit DAC channels.
Moreover, the ESP32 contains 10 capacitive sensing GPIOs, that detect touch and can be used to trigger events, or wake-up the ESP32 from deep sleep, for example.
There are many ways to program the ESP32 and ESP8266 boards. Both boards can be programmed with the Arduino core using the Arduino IDE or other IDEs (like VS Code with the PlatformIO extension).
These are good news, especially for those used to program the Arduino board and are familiar with the Arduino “programming language”.
Getting started with the ESP32 or ESP8266 using Arduino IDE and have your first project running is very simple. You can follow these guides:
Although you can program both boards using Arduino IDE, they might not be compatible with the same libraries and functions. Some libraries are just compatible with one of the boards. This means that most of the time, your ESP8266 code will not be compatible with the ESP32. However, usually, you need to make a few modifications.
We have a dedicated list of free tutorials and projects for the ESP32 and ESP8266 boards using the Arduino IDE that you might found useful:
Another popular way of programming the ESP32 and ESP8266 boards is using MicroPython firmware.
MicroPython is a re-implementation of Python 3 targeted for microcontrollers and embedded systems. MicroPython is very similar with regular Python. So, if you already know how to program in Python, you also know how to program in MicroPython.
In MicroPython, most Python scripts are compatible with both boards (unlike when using Arduino IDE). This means that most of the time, you can use the same script for ESP32 and ESP8266.
You can get started with MicroPython firmware on the ESP32 and ESP8266 very quickly by following our free guides:
So, at this point you may be wondering: Should I get an ESP8266 or an ESP32?
It really depends on what you want to do. There is space for both boards, and both have pros and cons.
The ESP8266 is cheaper than the ESP32. Although it doesn’t have as many functionalities, it works just fine for most simple DIY IoT projects. However, it has some limitations in the GPIO mapping, and it might not have enough pins for what you intend to do. If that’s the case, you should get an ESP32.
The ESP32 is much more powerful than the ESP8266, comes with more GPIOs with multiple functions, faster Wi-Fi, and supports Bluetooth. However, many people think that the ESP32 is more difficult to deal with than the ESP8266 because it is more complex. On the contrary, in our opinion, it is as easy to program the ESP32 as the ESP8266, especially if you intend to program it using the “Arduino language” or MicroPython.
The ESP32 has some cons too. The ESP32 is more expensive than the ESP8266. So, if you’re building a simple IoT project, the ESP8266 might do the trick for a lower price. Additionally, because the ESP8266 is “older” than the ESP32, some libraries and features are better developed for the ESP8266, and you’ll find more resources (forums, people with the same issues, and how to solve them, etc.). However, as time goes by, the ESP32 is being widely adopted, and these differences in terms of development and libraries won’t be noticeable.
My personal experience: in 2021, I use almost exclusively the ESP32 for IoT projects. It is more versatile, and it comes with much more functionalities like Bluetooth, different wake-up sources, many peripherals, and much more. Additionally, the price difference is not a big deal, in my opinion. Once you move to the ESP32, you won’t want to go back to the ESP8266.
Wrapping Up
We hope you’ve found our analysis ESP32 vs ESP8266 useful.
Just to wrap up the main differences between the ESP32 and ESP8266:
The ESP32 is faster than the ESP8266;
The ESP32 comes with more GPIOs with multiple functions;
The ESP32 supports analog measurements on 18 channels (analog-enabled pins) versus just one 10-bit ADC pin on the ESP8266;
The ESP32 supports Bluetooth while the ESP8266 doesn’t;
The ESP32 is dual-core, and the ESP8266 is single core;
The ESP8266 is cheaper than the ESP32;
The ESP8266 has a wider community (although we don’t think that at this point, the difference is that relevant);
For many IoT and Wi-Fi projects, the ESP8266 can do the job for a lower price;
Both boards can be programmed with the Arduino core using Arduino IDE or other supported IDEs.
Both boards support MicroPython firmware.
You might like reading the following ESP8266 and ESP32 related articles to have an idea of the selection of the most popular ESP32 and ESP8266 development boards:
So, if you’re a beginner, should you get started with the ESP32 or the ESP8266? At this point, we definitely recommend getting started with the ESP32 instead of the ESP8266. However, if you already have an ESP8266 board, you can get started with that board and then make the shift to the ESP32.
We have a vast selection of projects with these boards in the Random Nerd Tutorials blog to help you get started:
