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SunFounder PiCrawler Kit www.sunfounder.com Aug 02, 2022 CONTENTS 1 Component List and Assembly Instructions 3 2 About Robot HAT 5 3 Play with Python 3.1 Quick Guide on Python 3.2 Calibrate the PiCrawler 3.3 Move . . . . . . . . . . 3.4 Keyboard Control . . . 3.5 Sound Effect . . . . . . 3.6 Obstacle Avoidance . . 3.7 Computer Vision . . . . 3.8 Record Video . . . . . . 3.9 Bull Fight . . . . . . . . 3.10 Treasure Hunt . . . . . 3.11 Pose . . . . . . . . . . . 3.12 Adjust Posture . . . . . 3.13 Record New Step . . . . 3.14 Twist . . . . . . . . . . 3.15 Emotional Robot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7 28 30 33 34 37 40 46 48 51 55 58 61 64 65 Play with Ezblock 4.1 Quick Guide on EzBlock 4.2 Calibrate the PiCrawler 4.3 Move . . . . . . . . . . 4.4 Remote Control . . . . 4.5 Sound Effect . . . . . . 4.6 Obstacle Avoidance . . 4.7 Computer Vision . . . . 4.8 Bull Fight . . . . . . . . 4.9 Treasure Hunt . . . . . 4.10 Pose . . . . . . . . . . . 4.11 Adjust Posture . . . . . 4.12 Record New Step . . . . 4.13 Twist . . . . . . . . . . 4.14 Emotional Robot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 69 72 74 78 82 85 87 90 94 97 100 104 107 109 4 5 Appendix 111 5.1 Filezilla Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111 5.2 I2C Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 i 5.3 5.4 6 ii Remote Desktop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 About the Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 Copyright Notice 127 SunFounder PiCrawler Kit Thank you for choosing our PiCrawler. PiCrawler is a Raspberry Pi quadruped robot with aluminum alloy structure. It is equipped with a camera module, which can perform color recognition, face detection and other items; 12 metal gear servos support it to walk, dance, and pose various postures; the ultrasonic module on the body allows it to quickly detect obstacles in front of it; the expansion board-robot HAT is equipped with a speaker, allowing it to express emotions such as happiness and excitement. This document includes the list and assembly pdf, Robot HAT introduction and PiCrawler programming. The programming part is divided into two chapters: Play with Ezblock & Play with Python, each chapter allows you to explain how to make PiCrawler work the way you want. Ezblock Studio is a development platform developed by SunFounder for beginners, aiming to lower the barriers to entry for Raspberry Pi. It has two programming languages: Graphical and Python, which can be used on almost all different types of devices. With Bluetooth and Wi-Fi support, you can download codes on Ezblock Studio and remotely control Raspberry Pi. More experienced makers can use the popular programming language-Python. Content CONTENTS 1 SunFounder PiCrawler Kit 2 CONTENTS CHAPTER ONE COMPONENT LIST AND ASSEMBLY INSTRUCTIONS You need to check whether there are missing or damaged components according to the list first. If there are any problems, please contact us and we will solve them as soon as possible. Please follow the steps on the PDF to assemble. If the servo has been powered on, please do not turn the Servo shaft to avoid damage. Note: 1. Before assembling, you need to buy 2 18650 batteries and fully charge them, refer to About the Battery. 2. Robot HAT cannot charge the battery, so you need to buy a battery charger at the same time. • Component List and Assembly Instructions. 3 SunFounder PiCrawler Kit 4 Chapter 1. Component List and Assembly Instructions CHAPTER TWO ABOUT ROBOT HAT Robot HAT is a multifunctional expansion board that allows Raspberry Pi to be quickly turned into a robot. An MCU is on board to extend the PWM output and ADC input for the Raspberry Pi, as well as a motor driver chip, Bluetooth module, I2S audio module and mono speaker. As well as the GPIOs that lead out of the Raspberry Pi itself. It also comes with a Speaker, which can be used to play background music, sound effects and implement TTS functions to make your project more interesting. 5 SunFounder PiCrawler Kit Accepts 7-12V PH2.0 2pin power input with 2 power indicators. The board also has a user available LED and a button for you to quickly test some effects. Note: You can see more details in the Robot HAT Documentation. 6 Chapter 2. About Robot HAT CHAPTER THREE PLAY WITH PYTHON If you want to program in python, then you will need to learn some basic Python programming skills and basic knowledge of Raspberry Pi, please configure the Raspberry Pi first according to Quick Guide on Python. 3.1 Quick Guide on Python This section is to teach you how to install Raspberry Pi OS, configure wifi to Raspberry Pi, remote access to Raspberry Pi to run the corresponding code. If you are familiar with Raspberry Pi and can open the command line successfully, then you can skip the first 3 parts and then complete the last part. 3.1.1 What Do We Need? Required Components Raspberry Pi The Raspberry Pi is a low cost, credit-card sized computer that plugs into a computer monitor or TV, and uses a standard keyboard and mouse. It is a capable little device that enables people of all ages to explore computing, and to learn how to program in languages like Scratch and Python. 7 SunFounder PiCrawler Kit Power Adapter To connect to a power socket, the Raspberry Pi has a micro USB port (the same found on many mobile phones). You will need a power supply which provides at least 2.5 amps. Micro SD Card Your Raspberry Pi needs an Micro SD card to store all its files and the Raspberry Pi OS. You will need a micro SD card with a capacity of at least 8 GB Optional Components Screen To view the desktop environment of Raspberry Pi, you need to use the screen that can be a TV screen or a computer monitor. If the screen has built-in speakers, the Pi plays sounds via them. Mouse & Keyboard When you use a screen , a USB keyboard and a USB mouse are also needed. HDMI The Raspberry Pi has a HDMI output port that is compatible with the HDMI ports of most modern TV and computer monitors. If your screen has only DVI or VGA ports, you will need to use the appropriate conversion line. Case You can put the Raspberry Pi in a case; by this means, you can protect your device. 8 Chapter 3. Play with Python SunFounder PiCrawler Kit Sound or Earphone The Raspberry Pi is equipped with an audio port about 3.5 mm that can be used when your screen has no built-in speakers or when there is no screen operation. 3.1.2 Installing the OS Required Components Any Raspberry Pi 1 * Micro SD card 1 * Personal Computer Step 1 Raspberry Pi have developed a graphical SD card writing tool that works on Mac OS, Ubuntu 18.04 and Windows, and is the easiest option for most users as it will download the image and install it automatically to the SD card. Visit the download page: https://www.raspberrypi.org/software/. Click on the link for the Raspberry Pi Imager that matches your operating system, when the download finishes, click it to launch the installer. Step 2 When you launch the installer, your operating system may try to block you from running it. For example, on Windows I receive the following message: If this pops up, click on More info and then Run anyway, then follow the instructions to install the Raspberry Pi Imager. Step 3 Insert your SD card into the computer or laptop SD card slot. Step 4 3.1. Quick Guide on Python 9 SunFounder PiCrawler Kit Warning: Upgrading the Raspberry Pi OS to Debian Bullseye will cause some features to not work, so it is recommended to continue using the Debian Buster version. In the Raspberry Pi Imager, click CHOOSE OS -> Raspberry Pi OS(other). Scroll down to the end of the newly opened page and you will see Raspberry Pi OS(Legacy) and Raspberry Pi OS Lite(Legacy), these are security updates for Debian Buster, the difference between them is with or without the desktop. It is recommended to install Raspberry Pi OS(Legacy), the system with the desktop. 10 Chapter 3. Play with Python SunFounder PiCrawler Kit Step 5 Select the SD card you are using. Step 6 Press Ctrl+Shift+X to open the Advanced options page to enable SSH and configure wifi, these 2 items must be set, the others depend on your choice . You can choose to always use this image customization options. 3.1. Quick Guide on Python 11 SunFounder PiCrawler Kit Then scroll down to complete the wifi configuration and click SAVE. Note: wifi country should be set the two-letter ISO/IEC alpha2 code for the country in which you are using your Raspberry Pi, please refer to the following link: https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2#Officially_ assigned_code_elements 12 Chapter 3. Play with Python SunFounder PiCrawler Kit Step 7 Click the WRITE button. 3.1. Quick Guide on Python 13 SunFounder PiCrawler Kit Step 8 If your SD card currently has any files on it, you may wish to back up these files first to prevent you from permanently losing them. If there is no file to be backed up, click Yes. 14 Chapter 3. Play with Python SunFounder PiCrawler Kit Step 9 After waiting for a period of time, the following window will appear to represent the completion of writing. 3.1. Quick Guide on Python 15 SunFounder PiCrawler Kit 3.1.3 Set up Your Raspberry Pi If You Have a Screen If you have a screen, it will be easy for you to operate on the Raspberry Pi. Required Components Any Raspberry Pi 1 * Micro SD card 1 * HDMI cable 1 * Mouse 1 * Power Adapter 1 * Screen Power Adapter 1 * Screen 1 * Keyboard 1. Insert the SD card you’ve set up with Raspberry Pi OS into the micro SD card slot on the underside of your Raspberry Pi. 2. Plug in the Mouse and Keyboard. 3. Connect the screen to Raspberry Pi’s HDMI port and make sure your screen is plugged into a wall socket and switched on. Note: If you use a Raspberry Pi 4, you need to connect the screen to the HDMI0 (nearest the power in port). 4. Use the power adapter to power the Raspberry Pi. After a few seconds, the Raspberry Pi OS desktop will be displayed. 16 Chapter 3. Play with Python SunFounder PiCrawler Kit If You Have No Screen If you don’t have a display, you can log in to the Raspberry Pi remotely, but before that, you need to get the IP of the Raspberry Pi. Get the IP Address After the Raspberry Pi is connected to WIFI, we need to get the IP address of it. There are many ways to know the IP address, and two of them are listed as follows. 1. Checking via the router If you have permission to log in the router(such as a home network), you can check the addresses assigned to Raspberry Pi on the admin interface of router. The default hostname of the Raspberry Pi OS is raspberrypi, and you need to find it. (If you are using ArchLinuxARM system, please find alarmpi.) 2. Network Segment Scanning You can also use network scanning to look up the IP address of Raspberry Pi. You can apply the software, Advanced IP scanner and so on. Scan the IP range set, and the name of all connected devices will be displayed. Similarly, the default hostname of the Raspberry Pi OS is raspberrypi, if you haven’t modified it. 3.1. Quick Guide on Python 17 SunFounder PiCrawler Kit Use the SSH Remote Control We can open the Bash Shell of Raspberry Pi by applying SSH. Bash is the standard default shell of Linux. The Shell itself is a program written in C that is the bridge linking the customers and Unix/Linux. Moreover, it can help to complete most of the work needed. For Linux or/Mac OS X Users Step 1 Go to Applications->Utilities, find the Terminal, and open it. Step 2 Type in ssh pi@ip_address . “pi”is your username and “ip_address” is your IP address. For example: ssh pi@192.168.18.197 Step 3 Input”yes”. 18 Chapter 3. Play with Python SunFounder PiCrawler Kit Step 4 Input the passcode and the default password is raspberry. Step 5 We now get the Raspberry Pi connected and are ready to go to the next step. 3.1. Quick Guide on Python 19 SunFounder PiCrawler Kit Note: When you input the password, the characters do not display on window accordingly, which is normal. What you need is to input the correct password. For Windows Users If you’re a Windows user, you can use SSH with the application of some software. Here, we recommend PuTTY. Step 1 Download PuTTY. Step 2 Open PuTTY and click Session on the left tree-alike structure. Enter the IP address of the RPi in the text box under Host Name (or IP address) and 22 under Port (by default it is 22). 20 Chapter 3. Play with Python SunFounder PiCrawler Kit Step 3 Click Open. Note that when you first log in to the Raspberry Pi with the IP address, there prompts a security reminder. Just click Yes. Step 4 When the PuTTY window prompts “login as:”, type in “pi”(the user name of the RPi), and password: “raspberry” (the default one, if you haven’t changed it). Note: When you input the password, the characters do not display on window accordingly, which is normal. What you need is to input the correct password. If inactive appears next to PuTTY, it means that the connection has been broken and needs to be reconnected. 3.1. Quick Guide on Python 21 SunFounder PiCrawler Kit Step 5 Here, we get the Raspberry Pi connected and it is time to conduct the next steps. Note: If you are not satisfied with using the command window to control the Raspberry Pi, you can also use the remote desktop function, which can help us manage the files in the Raspberry Pi easily. For details on how to do this, please refer to Remote Desktop. 3.1.4 Download and Run the Code We can download the files by using git clone in the command line. Install robot-hat module first. cd /home/pi/ git clone https://github.com/sunfounder/robot-hat.git cd robot-hat sudo python3 setup.py install Note: Running setup.py will download some necessary components. You may fail to download due to network problems. You may need to download again at this time. In the following cases, enter Y and press Enter. 22 Chapter 3. Play with Python SunFounder PiCrawler Kit Then download the code and install vilib module. cd /home/pi/ git clone https://github.com/sunfounder/vilib.git cd vilib sudo python3 install.py Then download the code and install picrawler module. cd /home/pi/ git clone -b v2.0 https://github.com/sunfounder/picrawler.git cd picrawler sudo python3 setup.py install This step will take a little time, so please be patient. Finally, you need to run the script i2samp.sh to install the components required by the i2s amplifier, otherwise the pislot will have no sound. cd /home/pi/picrawler sudo bash i2samp.sh 3.1. Quick Guide on Python 23 SunFounder PiCrawler Kit Type y and press Enter to continue running the script. Type y and press Enter to run /dev/zero in the background. 24 Chapter 3. Play with Python SunFounder PiCrawler Kit Type y and press Enter to restart the machine. Note: If there is no sound after restarting, you may need to run the i2samp.sh script multiple times. 3.1.5 Servo Adjust To ensure that the servo has been properly set to 0°, first insert the rocker arm into the servo shaft and then gently rotate the rocker arm to a different angle. Follow the instructions on the assembly foldout, insert the battery holder cable and turn the power switch to the ON. 3.1. Quick Guide on Python 25 SunFounder PiCrawler Kit Wait for 1-2 minutes, there will be a sound to indicate that the Raspberry Pi boots successfully. Now, run servo_zeroing.py in the examples/ folder. cd /home/pi/picrawler/examples sudo python3 servo_zeroing.py Note: If you get an error, try re-enabling the Raspberry Pi’s I2C port, see: I2C Configuration. Next, plug the servo cable into the P11 port as follows. 26 Chapter 3. Play with Python SunFounder PiCrawler Kit At this point you will see the servo arm rotate to a specific position (0°). If the servo arm does not return to 0°, press the RST button to restart the Robot HAT. Now you can continue the installation as instructed on the assembly foldout. Note: • Do not unplug this servo cable before fixing it with the servo screw, you can unplug it after fixing it. • Do not rotate the servo while it is powered on to avoid damage; if the servo shaft is not inserted at the right angle, pull the servo out and reinsert it. • Before assembling each servo, you need to plug the servo cable into P11 and turn on the power to set its angle to 0°. 3.1. Quick Guide on Python 27 SunFounder PiCrawler Kit 3.2 Calibrate the PiCrawler Due to possible deviations during PiCrawler installation or limitations of the servos themselves, some servo angles may be slightly tilted, so you can calibrate them. Of course you can skip this chapter if you think the assembly is perfect and doesn’t require calibration. The specific steps are as follows: 1. Take out the assembly leaflet, turn it to the last page, and lay it flat on the table. Then place the PiCrawler as shown below, aligning its bottom with the outline on the calibration chart. 2. Run the calibration.py. cd /home/pi/picrawler/examples/calibration sudo python3 calibration.py After running the above code, you will see the following interface displayed in the terminal. 28 Chapter 3. Play with Python SunFounder PiCrawler Kit 3. Press 2 and 3 keys respectively to choose left 2 legsthen press w, a, s, d, r, and f keys to move them to the calibration point. 4. Now, change the calibration paper to the right and press the 1 and 4 keys to choose right 2 legs, then press w, a, s, d, r, and f keys to move them to the calibration point. 5. After the calibration is completed, press the space key to save, you will be prompted to enter Y to confirm, and then ctrl+c to exit the program to complete the calibration. 3.2. Calibrate the PiCrawler 29 SunFounder PiCrawler Kit After the assembly is complete, you can try to run the projects below. 3.3 Move This is PiCrawler’s first project. Perform its most basic function - move. 30 Chapter 3. Play with Python SunFounder PiCrawler Kit Run the Code cd /home/pi/picrawler/examples sudo python3 move.py After the code is executed, PiCrawler will perform the following actions in sequence: move forward, move backward, turn left, turn right, stand. Code Note: You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like pisloth\examples. After modifying the code, you can run it directly to see the effect. from picrawler import Picrawler from time import sleep crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9]) #crawler.set_offset([0,0,0,0,0,0,0,0,0,0,0,0]) def main(): speed = 100 while True: crawler.do_action('forward',2,speed) (continues on next page) 3.3. Move 31 SunFounder PiCrawler Kit (continued from previous page) sleep(0.05) crawler.do_action('backward',2,speed) sleep(0.05) crawler.do_action('turn left',2,speed) sleep(0.05) crawler.do_action('turn right',2,speed) sleep(0.05) crawler.do_action('turn left angle',2,speed) sleep(0.05) crawler.do_action('turn right angle',2,speed) sleep(0.05) crawler.do_step('stand',speed) sleep(1) if __name__ == "__main__": main() How it works? First, import the Picrawler class from the picrawler library you have installed, which contains all of PiCrawler’s actions and the functions that implement them. from picrawler import Picrawler Then instantiate the crawler class. crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9]) Finally use the crawler.do_action() function to make Pisloth move. crawler.do_action('forward',2,speed) crawler.do_action('backward',2,speed) crawler.do_action('turn left',2,speed) crawler.do_action('turn right',2,speed) crawler.do_action('turn left angle',2,speed) crawler.do_action('turn right angle',2,speed) In general, all movement of PiCrawler can be implemented with the do_action() function. It has 3 parameters: • motion_name is the name of specific actions, including: forward, turn right, turn left, backward, turn left angle, turn right angle. • step represents the number of each action is done, the default is 1. • speed indicates the speed of the action, the default is 50 and the range is 0~100. In addition, crawler.do_step('stand',speed) is also used here to make PiCrawler stand. The usage of this function will be explained in the following example. 32 Chapter 3. Play with Python SunFounder PiCrawler Kit 3.4 Keyboard Control In this project, we will learn how to use the keyboard to remotely control the PiCrawler. You can control the PiCrawler to move forward, backward, left, and right. Run the Code cd /home/pi/picrawler/examples sudo python3 keyboard_control.py Press keys on keyboard to control PiCrawler! * w: Forward * a: Turn left * s: Backward * d: Turn right * esc: Quit Code from picrawler import Picrawler from time import sleep import readchar crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9]) speed = 90 manual = ''' Press keys on keyboard to control PiCrawler! w: Forward a: Turn left s: Backward d: Turn right esc: Quit ''' def show_info(): print("\033[H\033[J",end='') print(manual) # clear terminal windows def main(): show_info() while True: key = readchar.readkey() key = key.lower() if key in('wsad'): if 'w' == key: crawler.do_action('forward',1,speed) elif 's' == key: crawler.do_action('backward',1,speed) elif 'a' == key: crawler.do_action('turn left',1,speed) elif 'd' == key: crawler.do_action('turn right',1,speed) sleep(0.05) show_info() elif key == readchar.key.CTRL_C or key in readchar.key.ESCAPE_SEQUENCES: print("\n Quit") break sleep(0.02) (continues on next page) 3.4. Keyboard Control 33 SunFounder PiCrawler Kit (continued from previous page) if __name__ == "__main__": main() How it works? PiCrawler should take appropriate action based on the keyboard characters read. The lower() function converts upper case characters into lower case characters, so that the letter remains valid regardless of case. while True: key = readchar.readkey() key = key.lower() if key in('wsad'): if 'w' == key: crawler.do_action('forward',1,speed) elif 's' == key: crawler.do_action('backward',1,speed) elif 'a' == key: crawler.do_action('turn left',1,speed) elif 'd' == key: crawler.do_action('turn right',1,speed) sleep(0.05) show_info() elif key == readchar.key.CTRL_C or key in readchar.key.ESCAPE_SEQUENCES: print("\n Quit") break 3.5 Sound Effect In this example, we use PiCrawler’s (to be precise, Robot HAT’s) sound effects. It consists of three parts, namely Muisc, Sound, Text to Speech. 34 Chapter 3. Play with Python SunFounder PiCrawler Kit Install i2samp Before using that functions, first activate the speaker so that it will be enabled and can make sounds. Run i2samp.sh in, and this script will install everything needed to use i2s amplifier. cd /home/pi/picrawler/ sudo bash i2samp.sh There will be several prompts asking to confirm the request. Respond to all prompts with a Y. After the changes have been made to the Raspberry Pi system, the computer will need to reboot for these changes to take effect. After rebooting, run the i2samp.sh script again to test the amplifier. If a sound successfully plays from the speaker, the configuration is complete. Run the Code cd /home/pi/picrawler/examples sudo python3 sound_effect.py After the code runs, please operate according to the prompt that printed on the terminal. Input key to call the function! * q: Play background music * 1: Play sound effect * 2: Play sound effect with threads * t: Text to speak 3.5. Sound Effect 35 SunFounder PiCrawler Kit Code from time import sleep from robot_hat import Music,TTS import readchar music = Music() tts = TTS() manual = ''' Input key to call the function! q: Play background music 1: Play sound effect 2: Play sound effect with threads t: Text to speak ''' def main(): print(manual) flag_bgm = False music.music_set_volume(20) tts.lang("en-US") while True: key = readchar.readkey() key = key.lower() if key == "q": flag_bgm = not flag_bgm if flag_bgm is True: music.background_music('./musics/sports-Ahjay_Stelino.mp3') else: music.music_stop() elif key == "1": music.sound_effect_play('./sounds/talk1.wav') sleep(0.05) music.sound_effect_play('./sounds/talk3.wav') sleep(0.05) music.sound_effect_play('./sounds/sign.wav') sleep(0.5) elif key =="2": music.sound_effect_threading('./sounds/talk1.wav') sleep(0.05) music.sound_effect_threading('./sounds/talk3.wav') sleep(0.05) music.sound_effect_threading('./sounds/sign.wav') sleep(0.5) elif key == "t": words = "Hello" tts.say(words) if __name__ == "__main__": main() How it works? 36 Chapter 3. Play with Python SunFounder PiCrawler Kit Functions related to background music include these: • music = Music() : Declare the object. • music.music_set_volume(20) : Set the volume, the range is 0~100. • music.background_music(./musics/sports-Ahjay_Stelino.mp3) : Play music files, here is the sports-Ahjay_Stelino.mp3 file under the ./musics path. • music.music_stop() : Stop playing background music. Note: You can add different sound effects or music to musics or sounds folder via Filezilla Software. Functions related to sound effects include these: • music = Music() • music.sound_effect_play('./sounds/talk1.wav') : Play the sound effect file, here is the talk1.wav file under the ./musics path. • muisc.sound_effect_threading('./sounds/talk1.wav') : Play the sound effect file in a new thread mode without suspending the main thread. Functions related to Text to Speech include these: • tts = TTS() • tts.say(words) : Text audio. • tts.lang("en-US") : Set the language. Note: Set the language by setting the parameters of lang("") with the following characters. Table 1: Language zh-CN en-US en-GB de-DE es-ES fr-FR it-IT Mandarin (Chinese) English-United States English-United Kingdom Germany-Deutsch España-Español France-Le français Italia-lingua italiana 3.6 Obstacle Avoidance In this project, picrawler will use an ultrasonic module to detect obstacles in front. When PiCrawler detects an obstacle, it will send a signal and look for another direction to move forward. 3.6. Obstacle Avoidance 37 SunFounder PiCrawler Kit Run the Code cd /home/pi/picrawler/examples sudo python3 avoid.py After the code runs, PiCrawler will walk forward. If it detects that the distance of the obstacle ahead is less than 10cm, it will stop and sound a warning, then turn left and stop. If there is no obstacle in the direction after turning left or the obstacle distance is greater than 10, it will continue to move forward. Code Note: You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like picrawler\examples. After modifying the code, you can run it directly to see the effect. from picrawler from robot_hat from robot_hat from robot_hat import time import os import import import import Picrawler TTS, Music Ultrasonic Pin tts = TTS() music = Music() (continues on next page) 38 Chapter 3. Play with Python SunFounder PiCrawler Kit (continued from previous page) crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9]) #crawler.set_offset([0,0,0,0,0,0,0,0,0,0,0,0]) sonar = Ultrasonic(Pin("D2") ,Pin("D3")) alert_distance = 15 speed = 100 def main(): distance = sonar.read() print(distance) if distance < 0: pass elif distance 220: crawler.do_action('turn right',1,speed) sleep(0.05) else : crawler.do_action('forward',2,speed) sleep(0.05) else : crawler.do_step('stand',speed) sleep(0.05) if __name__ == "__main__": main() How it works? In general, this project combines the knowledge points of Move, Computer Vision and Sound Effect. Its flow is shown in the figure below: 50 Chapter 3. Play with Python SunFounder PiCrawler Kit 3.10 Treasure Hunt Arrange a maze in your room and place six different color cards in six corners. Then control PiCrawler to search for these color cards one by one! Note: You can download and print the PDF Color Cards for color detection. Run the Code cd /home/pi/picrawler/examples sudo python3 treasure_hunt.py View the Image After the code runs, the terminal will display the following prompt: 3.10. Treasure Hunt 51 SunFounder PiCrawler Kit No desktop ! * Serving Flask app "vilib.vilib" (lazy loading) * Environment: production WARNING: Do not use the development server in a production environment. Use a production WSGI server instead. * Debug mode: off * Running on http://0.0.0.0:9000/ (Press CTRL+C to quit) Then you can enter http://:9000/mjpg in the browser to view the video screen. such as: http:/ /192.168.18.113:9000/mjpg Code from picrawler import Picrawler from time import sleep from robot_hat import Music,TTS from vilib import Vilib import readchar import random import threading crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9]) #crawler.set_offset([0,0,0,0,0,0,0,0,0,0,0,0]) music = Music() tts = TTS() manual = ''' Press keys on keyboard to control Picrawler! w: Forward a: Turn left s: Backward d: Turn right space: Say the target again esc: Quit ''' color = "red" color_list=["red","orange","yellow","green","blue","purple"] key_dict = { 'w': 'forward', 's': 'backward', 'a': 'turn_left', 'd': 'turn_right', } def renew_color_detect(): global color color = random.choice(color_list) Vilib.color_detect(color) tts.say("Look for " + color) key = None (continues on next page) 52 Chapter 3. Play with Python SunFounder PiCrawler Kit (continued from previous page) lock = threading.Lock() def key_scan_thread(): global key while True: key_temp = readchar.readkey() print('\r',end='') with lock: key = key_temp.lower() if key == readchar.key.SPACE: key = 'space' elif key == readchar.key.CTRL_C or key in readchar.key.ESCAPE_ ˓→SEQUENCES: key = 'quit' break sleep(0.01) def main(): global key action = None Vilib.camera_start(vflip=False,hflip=False) Vilib.display(local=False,web=True) sleep(0.8) speed = 100 print(manual) sleep(1) _key_t = threading.Thread(target=key_scan_thread) _key_t.setDaemon(True) _key_t.start() tts.say("game start") sleep(0.05) renew_color_detect() while True: ˓→ if Vilib.detect_obj_parameter['color_n']!=0 and Vilib.detect_obj_ parameter['color_w']>100: tts.say("will done") sleep(0.05) renew_color_detect() with lock: if key != None and key in ('wsad'): action = key_dict[str(key)] key = None elif key == 'space': tts.say("Look for " + color) key = None elif key == 'quit': _key_t.join() Vilib.camera_close() print("\n\rQuit") break if action != None: crawler.do_action(action,1,speed) action = None (continues on next page) 3.10. Treasure Hunt 53 SunFounder PiCrawler Kit (continued from previous page) sleep(0.05) if __name__ == "__main__": main() How it works? In general, this project combines the knowledge points of Keyboard Control, Computer Vision and Sound Effect. Its flow is shown in the figure below: 54 Chapter 3. Play with Python SunFounder PiCrawler Kit 3.11 Pose PiCrawler can assume a specific posture by writing a coordinate array. Here it assumes a raised right rear foot posture. Run the Code cd /home/pi/picrawler/examples sudo python3 do_step.py Code from picrawler import Picrawler from time import sleep crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9]) #crawler.set_offset([0,0,0,0,0,0,0,0,0,0,0,0]) ## [right front],[left front],[left rear],[right rear] new_step=[[50, 50, -80], [50, 50, -80],[80, 80, 0], [50, 50, -80]] def main(): speed = 100 while True: (continues on next page) 3.11. Pose 55 SunFounder PiCrawler Kit (continued from previous page) crawler.do_step('stand',speed) print(crawler.step_list.get('stand')) sleep(3) crawler.do_step(new_step,speed) print(new_step) sleep(3) if __name__ == "__main__": main() How it works? In this code, the code you need to pay attention to is this crawler.do_step(). Similar to do_action(), do_step() can also manipulate PiCrawler’s behavior. The difference is that the former can perform the continuous behavior of move forward, while the latter can be used to make separate gestures of stand and sit. It has two uses: One: It can write strings, directly use the step_list dictionary in the picrawler library. crawler.do_step('stand',speed) # "speed" indicates the speed of the step, the range is 0~100. Second: It can also write an array of 4 coordinate values. crawler.do_step([[50, 50, -80], [50, 50, -80],[80, 80, 0], [50, 50, -80]],speed) # These four coordinates are used to control the four legs of right front, left front, ˓→ left rear, and left rear respectively. Each foot has an independent coordinate system. As shown below: 56 Chapter 3. Play with Python SunFounder PiCrawler Kit You need to measure the coordinates of each toe individually. As shown below: 3.11. Pose 57 SunFounder PiCrawler Kit By the way: the step_list called in the first method also consists of an array containing 4 coordinate values. step_list = { "stand":[ [50, 50, [50, 50, [50, 50, [50, 50, ], "sit":[ [50, 50, [50, 50, [50, 50, [50, 50, ], } -80], -80], -80], -80] -33], -33], -33], -33] 3.12 Adjust Posture In this example, we use the keyboard to control the PiCrawler foot by foot and assume the desired posture. You can press the space bar to print out the current coordinate values. These coordinate values come in handy when you create unique actions for PiCrawler. 58 Chapter 3. Play with Python SunFounder PiCrawler Kit Run the Code cd /home/pi/picrawler/examples sudo python3 do_single_leg.py After the code runs, please operate according to the prompt that pops up in the terminal. • Press 1234 to select the feet separately, 1: right front foot, 2: left front foot, 3: left rear foot, 4: right rear foot • Press w, a, s, d, r, and f to slowly control the PiCrawler’s coordinate values. • Press space to print all coordinate values. • Press esc to exit. Code from picrawler import Picrawler from time import sleep import readchar crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9]) speed = 80 manual = ''' -------- PiCrawler Controller --------....... ....... ``````` ``````` (continues on next page) 3.12. Adjust Posture 59 SunFounder PiCrawler Kit (continued from previous page) ....... ``````` right front leg left front leg left rear leg right rear leg R: Z++ F: Z-- Esc: Quit ''' legs_list = ['right front', 'left front', 'left rear', 'right rear'] def main(): leg = 0 speed = 80 step = 2 print(manual) crawler.do_step('stand',speed) sleep(0.2) coordinate=crawler.current_step_all_leg_value() def show_info(): print("\033[H\033[J",end='') # clear terminal windows print(manual) print('%s : %s'%(leg+1, legs_list[leg])) print('coordinate: %s'%(coordinate)) show_info() while True: # readkey key = readchar.readkey() key = key.lower() # select the leg if key in ('1234'): leg = int(key) - 1 show_info() # move elif key in ('wsadrf'): if 'w' == key: coordinate[leg][1]=coordinate[leg][1] elif 's' == key: coordinate[leg][1]=coordinate[leg][1] elif 'a' == key: coordinate[leg][0]=coordinate[leg][0] elif 'd' == key: coordinate[leg][0]=coordinate[leg][0] elif 'r' == key: coordinate[leg][2]=coordinate[leg][2] elif 'f' == key: coordinate[leg][2]=coordinate[leg][2] + step - step - step + step + step - step crawler.do_single_leg(leg,coordinate[leg],speed) sleep(0.1) # coordinate=crawler.current_step_all_leg_value() (continues on next page) 60 Chapter 3. Play with Python SunFounder PiCrawler Kit (continued from previous page) show_info() # quit elif key == readchar.key.CTRL_C or key in readchar.key.ESCAPE_SEQUENCES: print("\n Quit") break sleep(0.05) if __name__ == "__main__": main() • current_step_all_leg_value() : Returns the coordinate values of all legs. • do_single_leg(leg,coordinate,speed) : Modify the coordinate value of a certain leg individually. 3.13 Record New Step We use the keyboard to control PiCrawler to make several poses in turn, and record these poses. Replay them later. Run the Code cd /home/pi/picrawler/examples sudo python3 record_new_step_by_keyboard.py After the code runs, please operate according to the prompt that pops up in the terminal. • Press 1234 to select the feet separately, 1: right front foot, 2: left front foot, 3: left rear foot, 4: right rear foot • Press w, a, s, d, r, and f to slowly control the PiCrawler’s coordinate values. • Press space to print all coordinate values. • Press p to have PiCrawler replay the recorded action. • Press esc to exit. Code from picrawler import Picrawler from time import sleep import sys import tty import termios import copy crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9]) #crawler.set_offset([0,0,0,0,0,0,0,0,0,0,0,0]) speed = 80 def readchar(): fd = sys.stdin.fileno() old_settings = termios.tcgetattr(fd) try: tty.setraw(sys.stdin.fileno()) ch = sys.stdin.read(1) finally: (continues on next page) 3.13. Record New Step 61 SunFounder PiCrawler Kit (continued from previous page) termios.tcsetattr(fd, termios.TCSADRAIN, old_settings) return ch manual = ''' Press keys on keyboard to control PiSloth! w: Y++ a: X-s: Y-d: X++ r: Z++ f: Z-1: Select right front leg 2: Select left front leg 3: Select left rear leg 4: Select right rear leg space: Print all leg coodinate & Save this step p: Play all saved step esc: Quit ''' new_step=[] def save_new_step(): new_step.append(copy.deepcopy(crawler.current_step_all_leg_value())) print(new_step) def play_all_new_step(): for step in new_step: crawler.do_step(step,speed) sleep(0.6) def main(): speed = 80 print(manual) crawler.do_step('sit',speed) leg = 0 coodinate=crawler.current_step_leg_value(leg) while True: key = readchar() key = key.lower() # print(key) if 'w' == key: coodinate[1]=coodinate[1]+2 elif 's' == key: coodinate[1]=coodinate[1]-2 elif 'a' == key: coodinate[0]=coodinate[0]-2 elif 'd' == key: coodinate[0]=coodinate[0]+2 elif 'r' == key: coodinate[2]=coodinate[2]+2 elif 'f' == key: coodinate[2]=coodinate[2]-2 elif '1' == key: (continues on next page) 62 Chapter 3. Play with Python SunFounder PiCrawler Kit (continued from previous page) leg=0 coodinate=crawler.current_step_leg_value(leg) elif '2' == key: leg=1 coodinate=crawler.current_step_leg_value(leg) elif '3' == key: leg=2 coodinate=crawler.current_step_leg_value(leg) elif '4' == key: leg=3 coodinate=crawler.current_step_leg_value(leg) elif chr(32) == key: print("[[right front],[left front],[left rear],[right rear]]") print("saved new step") print(crawler.current_step_all_leg_value()) save_new_step() elif 'p' == key: play_all_new_step() elif chr(27) == key:# 27 for ESC break sleep(0.05) crawler.do_single_leg(leg,coodinate,speed) print("\n q Quit") if __name__ == "__main__": main() How it works? This project was born out of Adjust Posture. Added recording and replay functions. The recording function is implemented by the following code. new_step=[] def save_new_step(): new_step.append(copy.deepcopy(crawler.current_step_all_leg_value())) print(new_step) Note: The assignment here needs to use the Deep Copy function, otherwise the new_step will not get a new array object when appending. The replay function is implemented by the following code. def play_all_new_step(): for step in new_step: crawler.do_step(step,speed) sleep(0.6) 3.13. Record New Step 63 SunFounder PiCrawler Kit 3.14 Twist We already know how to make PiCrawler assume a specific pose, the next step is to combine the poses to form a continuous action. Here, PiCrawler’s four feet are up and down in twos, jumping with the music. Run the Code cd /home/pi/picrawler/examples sudo python3 twist.py Code Note: You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like picrawler\examples. After modifying the code, you can run it directly to see the effect. from picrawler import Picrawler from time import sleep from robot_hat import Music music = Music() crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9]) #crawler.set_offset([0,0,0,0,0,0,0,0,0,0,0,0]) def twist(speed): ## [right front],[left front],[left rear],[left rear] new_step=[[50, 50, -80], [50, 50, -80],[50, 50, -80], [50, 50, -80]] for i in range(4): for inc in range(30,60,5): rise = [50,50,(-80+inc*0.5)] drop = [50,50,(-80-inc)] new_step[i]=rise new_step[(i+2)%4] = drop new_step[(i+1)%4] = rise new_step[(i-1)%4] = drop crawler.do_step(new_step,speed) def main(): music.background_music('./musics/sports-Ahjay_Stelino.mp3') music.music_set_volume(20) while True: twist(speed=100) if __name__ == "__main__": main() How it works? In this code, you need to pay attention to this part: 64 Chapter 3. Play with Python SunFounder PiCrawler Kit def twist(speed): ## [right front],[left front],[left rear],[right rear] new_step=[[50, 50, -80], [50, 50, -80],[50, 50, -80], [50, 50, -80]] for i in range(4): for inc in range(30,60,5): rise = [50,50,(-80+inc*0.5)] drop = [50,50,(-80-inc)] new_step[i]=rise new_step[(i+2)%4] = drop new_step[(i+1)%4] = rise new_step[(i-1)%4] = drop crawler.do_step(new_step,speed) Simply put, it uses two layers of for loops to make the new_step array produce continuous and regular changes, and at the same time, crawler.do_step() executes the posture to form a continuous action. You can intuitively get the coordinate value array corresponding to each pose from Adjust Posture. In addition, the example also played background music. The implementation method is as follows. Play music by importing the following libraries. from robot_hat import Music Declare a Music object. music = Music() Play the background music in the picrawler/examples/musics directory and set the volume to 20. You can also add music to the musics folder via Filezilla Software. music.background_music('./musics/sports-Ahjay_Stelino.mp3') music.music_set_volume(20) Note: You can add different sound effects or music to musics or sounds folder via Filezilla Software. 3.15 Emotional Robot This example shows several interesting custom actions of PiCrawler. Run the Code cd /home/pi/picrawler/examples sudo python3 emotional_robot.py Code Note: You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like picrawler\examples. After modifying the code, you can run it directly to see the effect. 3.15. Emotional Robot 65 SunFounder PiCrawler Kit from picrawler import Picrawler from time import sleep crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9]) #crawler.set_offset([0,0,0,0,0,0,0,0,0,0,0,0]) def handwork(speed): basic_step basic_step left_hand right_hand two_hand = = [] = crawler.step_list.get("sit") = crawler.mix_step(basic_step,0,[0,50,80]) = crawler.mix_step(basic_step,1,[0,50,80]) crawler.mix_step(left_hand,1,[0,50,80]) crawler.do_step('sit',speed) sleep(0.6) crawler.do_step(left_hand,speed) sleep(0.6) crawler.do_step(two_hand,speed) sleep(0.6) crawler.do_step(right_hand,speed) sleep(0.6) crawler.do_step('sit',speed) sleep(0.6) def twist(speed): new_step=[[50, 50, -80], [50, 50, -80],[50, 50, -80], [50, 50, -80]] for i in range(4): for inc in range(30,60,5): rise = [50,50,(-80+inc*0.5)] drop = [50,50,(-80-inc)] new_step[i]=rise new_step[(i+2)%4] = drop new_step[(i+1)%4] = rise new_step[(i-1)%4] = drop crawler.do_step(new_step,speed) ##"[[right front], [left front], [left rear], [left rear]]") def pushup(speed): up=[[80, 0, -100], [80, 0, -100],[0, 120, -60], [0, 120, -60]] down=[[80, 0, -30], [80, 0, -30],[0, 120, -60], [0, 120, -60]] crawler.do_step(up,speed) sleep(0.6) crawler.do_step(down,speed) sleep(0.6) def swimming(speed): for i in range(100): crawler.do_step([[100-i,i,0],[100-i,i,0],[0,120,-60+i/5],[0,100,-40-i/5]], ˓→speed) # main def main(): speed = 100 (continues on next page) 66 Chapter 3. Play with Python SunFounder PiCrawler Kit (continued from previous page) swimming(speed) pushup(speed) handwork(speed) twist(speed) sleep(0.05) if __name__ == "__main__": main() 3.15. Emotional Robot 67 SunFounder PiCrawler Kit 68 Chapter 3. Play with Python CHAPTER FOUR PLAY WITH EZBLOCK For beginners and novices, EzBlock is a software development platform offered by SunFounder for Raspberry Pi. Ezbock offers two programming environments: a graphical environment and a Python environment. It is available for almost all types of devices, including Mac, PC, and Android. Here is a tutorial to help you complete EzBlock installation, download, and use. 4.1 Quick Guide on EzBlock There are 2 parts here: • Servo Adjust allows you to keep all the servos at 0 degrees to complete a proper and safe assembly (otherwise you will probably damage the servos). • Install and Configure EzBlock Studio will guide you to download EzBlock Studio to play with your robot. 4.1.1 Servo Adjust When assembling to the part with the servo, you need to keep the servo at 0° and secure it with the servo screw. Please follow the tutorial below to do this. 1. Firstly, Install EzBlock OS(3.1) onto a Micro SD card, once the installation is complete, insert it into the Raspberry Pi. 2. To ensure that the servo has been properly set to 0°, first insert the rocker arm into the servo shaft and then gently rotate the rocker arm to a different angle. 69 SunFounder PiCrawler Kit 3. Follow the instructions on the assembly foldout, insert the battery holder cable and turn the power switch to the ON. Wait for 1-2 minutes, there will be a sound to indicate that the Raspberry Pi boots successfully. 4. Next, plug the servo cable into the P11 port as follows. 70 Chapter 4. Play with Ezblock SunFounder PiCrawler Kit 5. At this point you will see the servo arm rotate to a specific position (0°). If the servo arm does not return to 0°, press the RST button to restart the Robot HAT. 6. Now you can continue the installation as instructed on the assembly foldout. Note: • Do not unplug this servo cable before fastening this servo with the servo screw, you can unplug it after fastening. • Do not turn the servo while it is powered on to avoid damage; if the servo shaft is inserted at the wrong angle, pull out the servo and reinsert it. • Before assembling each servo, you need to plug the servo cable into P11 and turn on the power to set its angle to 0°. • This zeroing function will be disabled if you download a program to the robot later with the EzBlock APP. 4.1.2 Install and Configure EzBlock Studio As soon as the robot is assembled, you will need to carry out some basic operations. • Install EzBlock Studio(3.1): Download and install EzBlock Studio on your device or use the web-based version. • Connect the Product and EzBlock(3.1): Configure Wi-Fi, Bluetooth and calibrate before use. • Open and Run Examples(3.1): View or run the related example directly. 4.1. Quick Guide on EzBlock 71 SunFounder PiCrawler Kit 4.2 Calibrate the PiCrawler Note: After you connect the PiCrawler, there will be a calibration step. This is because of possible deviations in the installation process or limitations of the servos themselves, making some servo angles slightly tilted, so you can calibrate them in this step. But if you think the assembly is perfect and no calibration is needed, you can also skip this step. The calibration steps are as follows: 1. Take out the assembly leaflet, turn it to the last page, and lay it flat on the table. Then place the PiCrawler as shown below, aligning its bottom with the outline on the calibration chart. 2. Go back to EzBlock Studio, select one foot on the left, then click the 3 sets of X, Y and Z buttons, and let the toes slowly align with the calibration point. • The calibration buttons are used for fine-tuning, and you need to press these buttons multiple times to see the pin position change. • It is recommended to click the up button of Z axis to lift the foot up first, then go to adjust X and Y. 72 Chapter 4. Play with Ezblock SunFounder PiCrawler Kit 3. Align the other foot on the left in the same way. 4. After calibrating the left two feet, change the calibration paper to the right, and calibrate the right two feet according to the above method. 4.2. Calibrate the PiCrawler 73 SunFounder PiCrawler Kit Projects Here, we show you the projects of playing PiCrawler on Ezblock Studio. If you are new to these, you can refer to the code images inside each project to program, and can learn the use of blocks according to TIPS. If you don’t want to write these projects one by one, we have uploaded them to Ezblock Studio’s Examples page and you can run them directly or edit them and run them later. 4.3 Move This is PiCrawler’s first project. Perform its most basic function - move. 74 Chapter 4. Play with Ezblock SunFounder PiCrawler Kit Program Note: • You can write the program according to the following picture, please refer to the tutorial: How to Create a New Project?. • Or find the code with the same name on the Examples page of the EzBlock Studio and click Run or Edit directly. 4.3. Move 75 SunFounder PiCrawler Kit Click the Upload & Run button at the bottom right of the screen, and PiCrawler will execute “forward” and “backward” actions in sequence. How it works? First, you need to understand the program framework of Ezblock. as follows: 76 Chapter 4. Play with Ezblock SunFounder PiCrawler Kit All Ezblock projects contain these two blocks. The Start block runs at the beginning of the program and is executed only once, and is often used to set variables; the Forever block runs after Start, and will be executed repeatedly, and is often used to implement main functions. If you delete these two blocks, you can drag them back from the Basic category on the left. Next you need to understand the following blocks. do action allows PiCrawler to perform basic actions. You can modify the options in the first groove. For example, select “Turn Left”, “Back” and so on. The second groove can set the number of executions of the action, and only integer numbers greater than 0 can be written. The third groove can set the speed of the action, and only integers within 0~100 can be written. do step is similar to do action, but it is not an action but a static posture. Such as “stand”, “sit”. Both blocks can be dragged from the PiCrawler category on the left. 4.3. Move 77 SunFounder PiCrawler Kit 4.4 Remote Control In this project, we will learn how to remote control the PiCrawler. You can control the PiCrawler to move forward, backward, left, and right. Note: You can refer to How to Use the Remote Control Function?. Come and carry out this project smoothly. Program Note: • You can write the program according to the following picture, please refer to the tutorial: How to Create a New Project?. • Or find the code with the same name on the Examples page of the EzBlock Studio and click Run or Edit directly. 78 Chapter 4. Play with Ezblock SunFounder PiCrawler Kit Switch to the Remote Control interface, and you will see the following widgets. 4.4. Remote Control 79 SunFounder PiCrawler Kit After the program is running, you can activate PiCrawler through D-Pad. How it works? After dragging out the widget on the Remote Control interface, a category named Remote will appear in the block categories column of the programming interface. Here we add the D-Pad widget, so the D-Pad get value block appears here. D-Pad can be regarded as a four-in-one button. You can choose which button to read in the second groove of the block. When the button is pressed, the value is “1”; when the button is not pressed, the value is “0”. 80 Chapter 4. Play with Ezblock SunFounder PiCrawler Kit We used an if block (you can find it in the Logic category on the left) to make the PiCrawler move forward once when the UP button of the D-pad is pressed. You can click the gear icon on the upper left of the block to modify the shape of the if block to realize multiple judgment branches. if block is usually used with = block, = block can be modified to >, < and other conditions through the drop-down menu, please use it flexibly. 4.4. Remote Control 81 SunFounder PiCrawler Kit 4.5 Sound Effect In this example, we use PiCrawler’s (to be precise, Robot HAT’s) sound effects. It consists of three parts, namely Muisc, Sound, Text to Speech. Program Note: • You can write the program according to the following picture, please refer to the tutorial: How to Create a New Project?. • Or find the code with the same name on the Examples page of the EzBlock Studio and click Run or Edit directly. 82 Chapter 4. Play with Ezblock SunFounder PiCrawler Kit Switch to the Remote Control interface, and you will see the following widgets. 4.5. Sound Effect 83 SunFounder PiCrawler Kit After the program is running, you can press different buttons to make PiCrawler sound. How it works? Functions related to background music include these: Functions related to sound effects include these: Functions related to Text to Speech include these: 84 Chapter 4. Play with Ezblock SunFounder PiCrawler Kit 4.6 Obstacle Avoidance In this project, picrawler will use an ultrasonic module to detect obstacles in front. When PiCrawler detects an obstacle, it will send a signal and look for another direction to move forward. Program Note: • You can write the program according to the following picture, please refer to the tutorial: How to Create a New Project?. 4.6. Obstacle Avoidance 85 SunFounder PiCrawler Kit • Or find the code with the same name on the Examples page of the EzBlock Studio and click Run or Edit directly. How it works? You can find the following blocks in the Module category to achieve distance detection: 86 Chapter 4. Play with Ezblock SunFounder PiCrawler Kit It should be noted that the two pins of the block should correspond to the actual wiring, that is, trig-D2, echo-D3. Here is the main program. • Read the distance detected by ultrasonic module and filter out the values less than 0 (When the ultrasonic module is too far from the obstacle or cannot read the data correctly, distance Copy Current Connection to Site Manager after a successful Quick Connect, enter the name and click OK. Next time you will be able to connect by selecting the previously saved site inside File -> Site Manager. Step 3: Upload/download files. You can upload local files to Raspberry Pi by dragging and dropping them, or download the files inside Raspberry Pi files locally. 112 Chapter 5. Appendix SunFounder PiCrawler Kit 5.2 I2C Configuration Enable the I2C port of your Raspberry Pi (If you have enabled it, skip this; if you do not know whether you have done that or not, please continue). sudo raspi-config 3 Interfacing options P5 I2C 5.2. I2C Configuration 113 SunFounder PiCrawler Kit , then -> . 114 Chapter 5. Appendix SunFounder PiCrawler Kit 5.3 Remote Desktop There are two ways to control the desktop of the Raspberry Pi remotely: VNC and XRDP, you can use any of them. 5.3.1 VNC You can use the function of remote desktop through VNC. Enable VNC service The VNC service has been installed in the system. By default, VNC is disabled. You need to enable it in config. Step 1 Input the following command: sudo raspi-config Step 2 Choose 3 Interfacing Options by press the down arrow key on your keyboard, then press the Enter key. 5.3. Remote Desktop 115 SunFounder PiCrawler Kit Step 3 P3 VNC Step 4 Select Yes -> OK -> Finish to exit the configuration. Login to VNC Step 1 You need to download and install the VNC Viewer on personal computer. After the installation is done, open it. 116 Chapter 5. Appendix SunFounder PiCrawler Kit Step 2 Then select “New connection”. Step 3 Input IP address of Raspberry Pi and any Name. 5.3. Remote Desktop 117 SunFounder PiCrawler Kit Step 4 Double click the connection just created: 118 Chapter 5. Appendix SunFounder PiCrawler Kit Step 5 Enter Username (pi) and Password (raspberry by default). 5.3. Remote Desktop 119 SunFounder PiCrawler Kit Step 6 Now you can see the desktop of the Raspberry Pi: 120 Chapter 5. Appendix SunFounder PiCrawler Kit That’s the end of the VNC part. 5.3.2 XRDP Another method of remote desktop is XRDP, it provides a graphical login to remote machines using RDP (Microsoft Remote Desktop Protocol). Install XRDP Step 1 Login to Raspberry Pi by using SSH. Step 2 Input the following instructions to install XRDP. sudo apt-get update sudo apt-get install xrdp Step 3 Later, the installation starts. Enter “Y”, press key “Enter” to confirm. 5.3. Remote Desktop 121 SunFounder PiCrawler Kit Step 4 Finished the installation, you should login to your Raspberry Pi by using Windows remote desktop applications. Login to XRDP Step 1 If you are a Windows user, you can use the Remote Desktop feature that comes with Windows. If you are a Mac user, you can download and use Microsoft Remote Desktop from the APP Store, and there is not much difference between the two. The next example is Windows remote desktop. Step 2 Type in “mstsc” in Run (WIN+R) to open the Remote Desktop Connection, and input the IP address of Raspberry Pi, then click on “Connect”. Step 3 122 Chapter 5. Appendix SunFounder PiCrawler Kit Then the xrdp login page pops out. Please type in your username and password. After that, please click “OK”. At the first time you log in, your username is “pi” and the password is “raspberry”. Step 4 Here, you successfully login to RPi by using the remote desktop. 5.3. Remote Desktop 123 SunFounder PiCrawler Kit 5.4 About the Battery Applicable Parameters • 3.7V • 18650 • Rechargeable • Li-ion Battery • Button Top • No Protective Board Note: • Robot HAT cannot charge the battery, so you need to buy a battery charger. • When the two power indicators on the Robot HAT are off, it means the power is too low and the batteries need to be charged. Button Top vs Flat Top? Please choose battery with button top to ensure a good connection between the battery and the battery holder. 124 Chapter 5. Appendix SunFounder PiCrawler Kit Button Top Flat Top No protective board? You are recommend to use 18650 batteries without a protective board. Otherwise, the robot may be cut power and stop running because of the overcurrent protection of the protective board. Battery capacity? In order to keep the robot working for a long time, use large-capacity batteries as much as possible. It is recommended to purchase batteries with a capacity of 3000mAh and above. 5.4. About the Battery 125 SunFounder PiCrawler Kit 126 Chapter 5. Appendix CHAPTER SIX COPYRIGHT NOTICE All contents including but not limited to texts, images, and code in this manual are owned by the SunFounder Company. You should only use it for personal study,investigation, enjoyment, or other non-commercial or nonprofit purposes, under therelated regulations and copyrights laws, without infringing the legal rights of the author and relevant right holders. For any individual or organization that uses these for commercial profit without permission, the Company reserves the right to take legal action. 127