影片

事前準備

• Raspberry Pi 2 Model B
• 8 GB MicroSD 記憶卡
• 行動電源 (重量越輕越好)
• 無線USB網路卡 (Edimax EW-7811Un)
• 直流馬達控制晶片 (L293D)
• Webcam (Logitech C310)
• 直流馬達 x4
• 齒輪組 x4
• 輪子 x4
• 壓克力板 x2
• Android手機 (Android 4.0.3或更新的版本)
• 其它需要的電子材料，例如麵包板、麵包線、電池等

開發環境

• Java SE 8
• NetBeans

Raspberry Pi 2 Model B Spec

http://pi4j.com/pins/model-2b-rev1.html

L293D接線圖

製作Raspberry Pi OS image (官網步驟)

1. 從Raspberry官網download image (Raspbian)

2. 確認電腦有抓到SD card (假設SD card是在/dev/disk4):
   diskutil list

3. Unmount SD card:
   diskutil unmountDisk /dev/disk4

4. Build OS image to SD card:
   sudo dd bs=1m if=2015-05-05-raspbian-wheezy.img of=/dev/disk4

設定Edimax EW-7811Un無線網卡為hotspot (參考網頁)

1. 檢查network interface config
   sudo vi /etc/network/interfaces

   修改內容如下：

   auto lo
   iface lo inet loopback
   
   iface eth0 inet dhcp
   
   #auto wlan0
   allow-hotplug wlan0
   #iface wlan0 inet manual
   #wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
   
   iface wlan0 inet static
   address 192.168.8.1
   netmask 255.255.255.0
   gateway 192.168.1.1
   
   #iface default inet dhcp
   pre-up iptables-restore < /etc/iptables.ipv4.nat
   

2. 安裝DHCP server

   sudo apt-get install isc-dhcp-server
sudo vi /etc/dhcp/dhcpd.conf

   修改內容如下：

   #
   # Sample configuration file for ISC dhcpd for Debian
   #
   #
   
   # The ddns-updates-style parameter controls whether or not the server will
   # attempt to do a DNS update when a lease is confirmed. We default to the
   # behavior of the version 2 packages ('none', since DHCP v2 didn't
   # have support for DDNS.)
   ddns-update-style none;
   
   # option definitions common to all supported networks...
   #option domain-name "example.org";
   #option domain-name-servers ns1.example.org, ns2.example.org;
   
   default-lease-time 600;
   max-lease-time 7200;
   
   # If this DHCP server is the official DHCP server for the local
   # network, the authoritative directive should be uncommented.
   authoritative;
   
   # Use this to send dhcp log messages to a different log file (you also
   # have to hack syslog.conf to complete the redirection).
   log-facility local7;
   
   # No service will be given on this subnet, but declaring it helps the
   # DHCP server to understand the network topology.
   
   #subnet 10.152.187.0 netmask 255.255.255.0 {
   #}
   
   # This is a very basic subnet declaration.
   
   #subnet 10.254.239.0 netmask 255.255.255.224 {
   #  range 10.254.239.10 10.254.239.20;
   #  option routers rtr-239-0-1.example.org, rtr-239-0-2.example.org;
   #}
   
   # This declaration allows BOOTP clients to get dynamic addresses,
   # which we don't really recommend.
   
   #subnet 10.254.239.32 netmask 255.255.255.224 {
   #  range dynamic-bootp 10.254.239.40 10.254.239.60;
   #  option broadcast-address 10.254.239.31;
   #  option routers rtr-239-32-1.example.org;
   #}
   
   # A slightly different configuration for an internal subnet.
   #subnet 10.5.5.0 netmask 255.255.255.224 {
   #  range 10.5.5.26 10.5.5.30;
   #  option domain-name-servers ns1.internal.example.org;
   #  option domain-name "internal.example.org";
   #  option routers 10.5.5.1;
   #  option broadcast-address 10.5.5.31;
   #  default-lease-time 600;
   #  max-lease-time 7200;
   #}
   
   # Hosts which require special configuration options can be listed in
   # host statements.   If no address is specified, the address will be
   # allocated dynamically (if possible), but the host-specific information
   # will still come from the host declaration.
   
   #host passacaglia {
   #  hardware ethernet 0:0:c0:5d:bd:95;
   #  filename "vmunix.passacaglia";
   #  server-name "toccata.fugue.com";
   #}
   
   # Fixed IP addresses can also be specified for hosts.   These addresses
   # should not also be listed as being available for dynamic assignment.
   # Hosts for which fixed IP addresses have been specified can boot using
   # BOOTP or DHCP.   Hosts for which no fixed address is specified can only
   # be booted with DHCP, unless there is an address range on the subnet
   # to which a BOOTP client is connected which has the dynamic-bootp flag
   # set.
   #host fantasia {
   #  hardware ethernet 08:00:07:26:c0:a5;
   #  fixed-address fantasia.fugue.com;
   #}
   
   # You can declare a class of clients and then do address allocation
   # based on that.   The example below shows a case where all clients
   # in a certain class get addresses on the 10.17.224/24 subnet, and all
   # other clients get addresses on the 10.0.29/24 subnet.
   
   #class "foo" {
   #  match if substring (option vendor-class-identifier, 0, 4) = "SUNW";
   #}
   
   #shared-network 224-29 {
   #  subnet 10.17.224.0 netmask 255.255.255.0 {
   #    option routers rtr-224.example.org;
   #  }
   #  subnet 10.0.29.0 netmask 255.255.255.0 {
   #    option routers rtr-29.example.org;
   #  }
   #  pool {
   #    allow members of "foo";
   #    range 10.17.224.10 10.17.224.250;
   #  }
   #  pool {
   #    deny members of "foo";
   #    range 10.0.29.10 10.0.29.230;
   #  }
   #}
   
   subnet 192.168.8.0 netmask 255.255.255.0 {
   range 192.168.8.10 192.168.8.50;
   option broadcast-address 192.168.8.255;
   option routers 192.168.8.1;
   default-lease-time 600;
   max-lease-time 7200;
   option domain-name "local";
   option domain-name-servers 8.8.8.8, 8.8.4.4;
   }	
   

3. 讓wireless module成為預設DHCP device

   sudo nano /etc/default/isc-dhcp-server

   修改 INTERFACES="" 變成 INTERFACES="wlan0"

   重啟DHCP server

   sudo service isc-dhcp-server restart

4. 安裝 access point daemon

   sudo apt-get install hostapd

   sudo vi /etc/hostapd/hostapd.conf

   並修改設定檔如下：

   interface=wlan0
   #driver=nl80211
   driver=rtl871xdrv
   ssid=SpyGear
   hw_mode=g
   channel=6
   macaddr_acl=0
   auth_algs=1
   ignore_broadcast_ssid=0
   wpa=2
   wpa_passphrase=12345678
   wpa_key_mgmt=WPA-PSK
   wpa_pairwise=TKIP
   rsn_pairwise=CCMP
   

5. 設定router table

   sudo iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
   sudo iptables -A FORWARD -i eth0 -o wlan0 -m state --state RELATED,ESTABLISHED -j ACCEPT
   sudo iptables -A FORWARD -i wlan0 -o eth0 -j ACCEPT
   

6. sudo reboot

   即可透過如下資訊連上Pi

   SSID: SpyGear
   Password: 12345678
   

安裝Webcam串流模組 (mjpg-streamer)

0. 取得Raspberry Pi的IP (nmap)

   安裝nmap:
   brew install nmap

   掃整個網段:
   nmap -sP 192.168.1.0-255

   掃到使用中的IP list:
   Starting Nmap 6.47 ( http://nmap.org ) at 2015-05-06 21:32 CST
   Strange error from connect (65):No route to host
   Nmap scan report for router.asus.com (192.168.1.1)
   Host is up (0.0074s latency).
   Nmap scan report for raspberrypi (192.168.1.62)
   Host is up (0.0028s latency).
   Nmap scan report for android-194e (192.168.1.80)
   Host is up (0.049s latency).
   Nmap scan report for my-mac (192.168.1.82)
   Host is up (0.00028s latency).
   Nmap scan report for android-25b5 (192.168.1.102)
   Host is up (0.042s latency).
   Nmap done: 256 IP addresses (5 hosts up) scanned in 2.36 seconds

1. 登入Raspberry Pi
   ssh pi@192.168.1.62

2. 安裝相關套件
   sudo apt-get install subversion
sudo apt-get install libjpeg8-dev
sudo apt-get install imagemagick

3. 下載mjpg-streamer模組
   svn co https://mjpg-streamer.svn.sourceforge.net/svnroot/mjpg-streamer mjpg-streamer

4. 編譯mjpg-streamer模組
   cd mjpg-streamer
make

5. 檢查Webcam是否有接上Raspberry Pi
   lsusb

安裝MQTT broker - Mosquitto

0. 取得Raspberry Pi的IP (nmap)
   參考前面步驟

1. 登入Raspberry Pi
   參考前面步驟

2. 安裝Mosquitto (MQTT Broker Server)
   apt-get install mosquitto

3. 修改Raspberry Pi設定檔
   sudo vi /etc/hosts

4. 修改Raspberry Pi的IP
   192.168.1.62 RaspberryPi

5. 重啟Raspberry Pi
   sudo reboot

Raspberry Pi目錄結構

/home/pi/
├── dist <-- MQTT message
├── mjpg_streamer <-- Webcam
└── webwork

複製SpyGearPi到Raspberry Pi

scp SpyGear.jar pi@192.168.1.62:/home/pi/dist/

啟動mjpg_streamer服務

cd ~/mjpg_streamer
./mjpg_streamer -i "./input_uvc.so -y -r QVGA -f 15" -o "./output_http.so -w ./www"

丟到背景執行
Ctrl + Z

切換到背景
bg

切換到前景
fg

啟動SpyGearPi

cd ~/dist
sudo java -jar SpyGearPi.jar