Shuichi Tsutsumi: Practical Core Bluetooth in IoT & Wearable projects

Presented at AltConf 2016

Transcript

1. Practical Core Bluetooth in IoT & Wearable projects Shuichi Tsutsumi @shu223 iOS Freelancer UIKonf 2016 - Berlin
2. Overview • Basics of Core Bluetooth • Practical Core Bluetooth
3. Bluetooth Low Energy?
4. Bluetooth Low Energy (BLE) • Wireless technology - no network infrastructure required
5. Bluetooth Low Energy (BLE) • Wireless technology - no network infrastructure required Wi-Fi
6. Bluetooth Low Energy (BLE) • Wireless technology - no network infrastructure required BLE
7. • Low energy
8. • Low energy • NOT compatible with Classic BT
9. • Low energy • NOT compatible with Classic BT • Uses 2.4 GHz radio frequencies
10. • Low energy • NOT compatible with Classic BT • Uses 2.4 GHz radio frequencies • Marketed by the Bluetooth SIG
11. • Low energy • NOT compatible with Classic BT • Uses 2.4 GHz radio frequencies • Marketed by the Bluetooth SIG • etc…
12. • Low energy • NOT compatible with Classic BT • Uses 2.4 GHz radio frequencies • Marketed by the Bluetooth SIG • etc…
13. The most important thing for iOS developers
14. The API ‘Core Bluetooth’ is open for developers
15. The API ‘Core Bluetooth’ is open for developers • API for Classic BT is NOT open. - Requires MFi certification.
16. BLE is almost the ONLY way to enable iOS apps to communicate with external hardware without infrastructure or MFi.
17. Basics of Core Bluetooth
19. Moff Band Moff App
20. Moff Band Moff App BLE Connection
21. Moff Band Moff App BLE Connection Sensors - Gyroscope - Accelerometer
22. Moff Band Moff App Sensor Data BLE Connection Sensors - Gyroscope - Accelerometer
23. Moff Band Moff App Sensor Data BLE Connection Sensors - Gyroscope - Accelerometer Analyze sensor data
24. Moff Band Moff App Sensor Data BLE Connection Sensors - Gyroscope - Accelerometer Analyze sensor data Recognize - Gesture - Posture
25. Moff Band Moff App Sensor Data BLE Connection Sensors - Gyroscope - Accelerometer Analyze sensor data Recognize - Gesture - Posture Play sounds
26. Sensor Data How sensor data is sent with Core Bluetooth BLE Connection
27. Step 1. Scan
28. Step 1. Scan: Search for nearby BLE devices
29. Step 1. Scan: Search for nearby BLE devices
30. Step 1. Scan Advertise : Search for nearby BLE devices
31. Scan Step 1. Scan Advertise : Search for nearby BLE devices
32. Scan Step 1. Scan Advertise : Search for nearby BLE devices centralManager.scanForPeripheralsWithServices(nil, options: nil)
33. Scan Step 1. Scan Advertise Discover : Search for nearby BLE devices
34. Scan Step 1. Scan Advertise Discover : Search for nearby BLE devices func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber!) { print(“Discovered a BLE device!”) }
35. Scan Step 1. Scan Advertise Discover : Search for nearby BLE devices func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber!) { print(“Discovered a BLE device!”) } Central
36. Scan Step 1. Scan Advertise Discover : Search for nearby BLE devices func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber!) { print(“Discovered a BLE device!”) } Peripheral Central
37. Step 2. Connect
38. Connect Step 2. Connect
39. Connect Step 2. Connect centralManager.connectPeripheral(peripheral, options: nil)
40. Connect Step 2. Connect centralManager.connectPeripheral(peripheral, options: nil) func centralManager(central: CBCentralManager, didConnectPeripheral peripheral: CBPeripheral) { print(“Connected!”) }
41. Step 3. Subscribe
42. Step 3. Subscribe: Ready to receive data
43. Step 3. Subscribe: Ready to receive data GATT = Generic Attribute Profile
44. Moff Service xx Service Step 3. Subscribe: Ready to receive data GATT = Generic Attribute Profile
45. Moff Service xx Service Button Characteristic xx Characteristic Sensor Characteristic Step 3. Subscribe: Ready to receive data GATT = Generic Attribute Profile
46. Moff Service xx Service Button Characteristic xx Characteristic Sensor Characteristic Subscribe (Request to be notified) Step 3. Subscribe: Ready to receive data GATT = Generic Attribute Profile
47. Moff Service xx Service Button Characteristic xx Characteristic Sensor Characteristic Subscribe (Request to be notified) Step 3. Subscribe: Ready to receive data GATT = Generic Attribute Profile peripheral.setNotifyValue(true, forCharacteristic: c)
48. Step 4. Notify Moff Service Sensor Characteristic xxxx Characteristic
49. Step 4. Notify Moff Service Sensor Characteristic xxxx Characteristic Update the value
50. Step 4. Notify Notify subscribers Moff Service Sensor Characteristic xxxx Characteristic Update the value
51. Step 4. Notify Notify subscribers Moff Service Sensor Characteristic xxxx Characteristic Update the value func peripheral(peripheral: CBPeripheral, didUpdateValueForCharacteristic characteristic: CBCharacteristic, error: NSError?) { print(“Received sensor data!”) }
52. Step 4. Notify Notify subscribers Moff Service Sensor Characteristic xxxx Characteristic Update the value func peripheral(peripheral: CBPeripheral, didUpdateValueForCharacteristic characteristic: CBCharacteristic, error: NSError?) { print(“Received sensor data!”) }
53. Hardware Side?
54. Hardware Side? I’m sorry, I don’t know…
55. BLE
56. BLE iOS Engineer
57. BLE iOS Engineer
58. BLE Firmware Engineer iOS Engineer
59. BLE Firmware Engineer iOS Engineer
60. HW Projects I’ve worked on as an iOS engineer
61. Wheelchair ‘WHILL’
62. Wheelchair ‘WHILL’
63. Wearable Walkie-Talkie ‘BONX’
64. Wearable Walkie-Talkie ‘BONX’
65. Wearable Walkie-Talkie ‘BONX’
66. Group conversation system with VoIP - Detects the human voice - Cuts out all background noise
67. → Can be used even in areas with poor coverage! Group conversation system with VoIP - Detects the human voice - Cuts out all background noise
68. BLE for BONX
69. BLE for BONX
70. BLE for BONX
71. IoT for Cars ‘SmartDrive’
72. Printable Open-Source Humanoid “PLEN2”
73. Music for the Deaf %BJUP
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74. Music for the Deaf %BJUP
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75. Music for the Deaf %BJUP
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76. Music for the Deaf %BJUP
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77. Music for the Deaf %BJUP
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78. Practical Core Bluetooth
79. Defining GATT
80. GATT to send sensor data Foo Service Sensor Data Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Bar Service xx Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: acc x, acc y, acc z, gyro x, gyro y, gyro z (2bytes for each) xx Characteristic
81. GATT to send sensor data Foo Service Sensor Data Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Bar Service xx Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: acc x, acc y, acc z, gyro x, gyro y, gyro z (2bytes for each) xx Characteristic
82. GATT to send sensor data Foo Service Sensor Data Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Bar Service xx Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: acc x, acc y, acc z, gyro x, gyro y, gyro z (2bytes for each) xx Characteristic
83. GATT to send sensor data Foo Service Sensor Data Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Bar Service xx Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: acc x, acc y, acc z, gyro x, gyro y, gyro z (2bytes for each) xx Characteristic
84. GATT to send sensor data Foo Service Sensor Data Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Bar Service xx Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: acc x, acc y, acc z, gyro x, gyro y, gyro z (2bytes for each) xx Characteristic
85. GATT to send sensor data Foo Service Sensor Data Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Bar Service xx Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: acc x, acc y, acc z, gyro x, gyro y, gyro z (2bytes for each) xx Characteristic
86. GATT to send button interactions Foo Service Button Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: 0x01 or 0x00
87. GATT to send button interactions Foo Service Button Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: 0x01 or 0x00
88. GATT to send button interactions Foo Service Button Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: 0x01 or 0x00
89. GATT to send button interactions Foo Service Button Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: 0x01 or 0x00 Button interactions
90. GATT to send button interactions Foo Service Button Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: 0x01 or 0x00 Button interactions
91. GATT to send button interactions Foo Service Button Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: 0x01 or 0x00 Button interactions
92. GATT to send button interactions Foo Service Button Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Notify Value: 0x01 or 0x00 Button interactions Y
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93. GATT for remote control Foo Service Remote Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Write Value: Horizontal (-100 ~ 100), Vertical (-100 ~ 100)
94. GATT for remote control Foo Service Remote Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Write Value: Horizontal (-100 ~ 100), Vertical (-100 ~ 100)
95. GATT for remote control Foo Service Remote Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Write Value: Horizontal (-100 ~ 100), Vertical (-100 ~ 100) values
96. GATT for remote control Foo Service Remote Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Write Value: Horizontal (-100 ~ 100), Vertical (-100 ~ 100) values
97. GATT for remote control Foo Service Remote Control Characteristic UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx Properties: Write Value: Horizontal (-100 ~ 100), Vertical (-100 ~ 100) values
98. How to define GATT 1. Create UUID for the service & characteristic 2. Define the properties (Read, Notify, Write, etc.) Peripheral → Central: Notify 
 Central → Peripheral: Write 3. Define the value format Usually limited to 20 bytes $ uuidgen CEEA31BC-BEAC-4A78-B7ED-FC96B6254D4C
99. Reference: GATT profiles by Bluetooth SIG
100. Defining background behaviors
101. Background behaviors on iOS • Very limited - Listening to music - Getting location data - Downloading data
102. Imagine
103. If BLE didn’t work in the background…
105. You would have to always keep the app in the foreground, while snowboarding!
107. You would have to launch the app whenever you go driving!
108. What functions can be used in the background?
109. What functions can be used in the background? • Scanning peripherals
110. What functions can be used in the background? • Scanning peripherals • Connecting with peripherals
111. What functions can be used in the background? • Scanning peripherals • Connecting with peripherals • Reading characteristics’ value
112. What functions can be used in the background? • Scanning peripherals • Connecting with peripherals • Reading characteristics’ value • Writing characteristics’ value
113. What functions can be used in the background? • Scanning peripherals • Connecting with peripherals • Reading characteristics’ value • Writing characteristics’ value • Receiving notifications
114. What functions can be used in the background? • Scanning peripherals • Connecting with peripherals • Reading characteristics’ value • Writing characteristics’ value • Receiving notifications Almost all functions can be used even in the background!
115. How to support background mode
117. Just check this box!
118. Limitations
119. Limitations • Longer intervals for scanning
120. Limitations • Longer intervals for scanning • Must explicitly specify one or more services to scan
121. Limitations • Longer intervals for scanning • Must explicitly specify one or more services to scan • CBCentralManagerOptionShowPowerAlertKey option is ignored
122. Limitations • Longer intervals for scanning • Must explicitly specify one or more services to scan • CBCentralManagerOptionShowPowerAlertKey option is ignored Resources - Core Bluetooth Programming Guide - Core Bluetooth Framework Reference (also in headers)
123. If the app in the background is killed by the system…
125. State Preservation and Restoration
126. State Preservation and Restoration The system takes over the BLE tasks even after the app is killed.
127. State Preservation and Restoration The system takes over the BLE tasks even after the app is killed. - Preserves the state of the app’s central managers and continues the BLE tasks on their behalf.
128. State Preservation and Restoration The system takes over the BLE tasks even after the app is killed. - Preserves the state of the app’s central managers and continues the BLE tasks on their behalf. - Relaunches the app into the background and calls the corresponding delegate method.
129. State Preservation and Restoration The system takes over the BLE tasks even after the app is killed. - Preserves the state of the app’s central managers and continues the BLE tasks on their behalf. - Relaunches the app into the background and calls the corresponding delegate method. → The app can handle BLE events!
131. • The app is killed by the system
132. • The app is killed by the system • The user pushes the button on the peripheral device
133. • The app is killed by the system • The user pushes the button on the peripheral device • The system receives the notification
134. • The app is killed by the system • The user pushes the button on the peripheral device • The system receives the notification • The app is relaunched in the BG and the delegate method is called.
135. func peripheral(peripheral: CBPeripheral, didUpdateValueForCharacteristic characteristic: CBCharacteristic, error: NSError?) { print(“Received the characteristic data!”) } • The app is killed by the system • The user pushes the button on the peripheral device • The system receives the notification • The app is relaunched in the BG and the delegate method is called.
136. func peripheral(peripheral: CBPeripheral, didUpdateValueForCharacteristic characteristic: CBCharacteristic, error: NSError?) { print(“Received the characteristic data!”) } • The app is killed by the system • The user pushes the button on the peripheral device • The system receives the notification • The app is relaunched in the BG and the delegate method is called. The app can process the button interaction!
137. Implementation
138. Implementation • Add an option when initializing the CBCentralManager object. let options = [ CBCentralManagerOptionRestoreIdentifierKey: "somekey" ] centralManager = CBCentralManager( delegate: self, queue: queue, options: options)
139. Implementation • Implement the delegate method which is called when the app is restored. func centralManager(central: CBCentralManager, willRestoreState dict: [String : AnyObject]) { print("Restored") }
140. Testing the restoration
141. Testing the restoration • Kill the app as if it was killed by the iOS kill(getpid(), SIGKILL);
142. How to test without HW prototypes
143. Did the HW prototypes exist when develop the apps? Projects HW prototypes existed? Moff YES WHILL NO BONX NO SmartDrive YES PLEN2 NO Music for the Deaf NO
144. Development Kit
145. Development Kit BLE Module
146. Development Kit BLE Module Display
147. Development Kit BLE Module Display USB interface
148. Development Kit BLE Module Display USB interface Battery box
149. Development Kit Can start development without creating a circuit ourselves BLE Module Display USB interface Battery box
151. Development Kit
152. Development Kit App
153. Development Kit App BLE
154. Horizontal (-100~100) / Vertical (-100~100) Development Kit App BLE
156. Emulator App
157. Emulator App • Develop another iOS app as the alternative to the peripheral device
158. Emulator App • Develop another iOS app as the alternative to the peripheral device • Use CBPeripheralManager
159. Emulator App • Develop another iOS app as the alternative to the peripheral device • Use CBPeripheralManager • Easier for iOS engineers
163. =
164. Multi-Function Control • Single Tap • Double Tap • Long Press • Very Long Press =
165. Troubleshooting
166. Can’t find the peripheral Scan ?
167. Can’t connect Find
168. Can’t connect Connect ×
169. • Connection dropped
170. • Connection dropped • Can’t discover services or characteristics
171. • Connection dropped • Can’t discover services or characteristics • Fail to write
172. • Connection dropped • Can’t discover services or characteristics • Fail to write • Incorrect characteristic values
173. • Connection dropped • Can’t discover services or characteristics • Fail to write • Incorrect characteristic values • Incorrect behaviors in the background
174. • Connection dropped • Can’t discover services or characteristics • Fail to write • Incorrect characteristic values • Incorrect behaviors in the background • etc…
175. Identify which side the problem is on Is the problem on the central side or on the peripheral side? → Compare with another iOS app like ‘LightBlue’
176. Can’t find the peripheral • Scanning, but can’t find the peripheral device
177. Can’t find the peripheral • Scanning, but can’t find the peripheral device Scan
178. Can’t find the peripheral • Scanning, but can’t find the peripheral device Scan but ‘didDiscover’ method isn’t called
179. Can’t find the peripheral • Scan with another iOS app Scan
180. Can’t find the peripheral • Scan with another iOS app Scan Discovered peripherals
181. Can’t connect, etc. Connect
182. Can’t connect, etc. Connect Services & Characteristics
183. Other debugging tools
184. Bluetooth Explorer
185. Bluetooth Explorer An OS X app made by Apple
187. Low Energy Devices
188. Low Energy Devices Scan, Connect
189. Low Energy Devices Scan, Connect Details of services and characteristics
190. Low Energy Devices Scan, Connect Details of services and characteristics Write, Read, Register Notify (Subscribe)
191. func centralManager( central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber!) { print(advertisementData) }
192. func centralManager( central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber!) { print(advertisementData) } Filtered by iOS!
193. func centralManager( central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber!) { print(advertisementData) } Filtered by iOS! → Can’t see all of the advertisement data
194. func centralManager( central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber!) { print(advertisementData) } Filtered by iOS! e.g. Can’t see the ‘Manufacture Data’ field of iBeacon → Can’t see all of the advertisement data
196. Not filtered → Can see the ‘Manufacture Data’ field of iBeacon
197. Packet Logger
198. Packet Logger An OS X app made by Apple
201. How to get
202. How to get
203. How to get Download ‘Hardware IO Tools for Xcode’
204. How to get Download ‘Hardware IO Tools for Xcode’
205. How to get Download ‘Hardware IO Tools for Xcode’
206. How to get Download ‘Hardware IO Tools for Xcode’
207. App Review
209. MSRP $13,995
210. Costing too much
211. Not enough devices when submitting
212. Videos for review
213. Videos for review • Show how the app works with the peripheral device
214. Videos for review • Show how the app works with the peripheral device • Not need to be cool!
216. • Shoot with iPhone
217. • Shoot with iPhone • Edit with iMovie
218. Recap • What is Bluetooth Low Energy? • Basics of Core Bluetooth with an actual product • Practical Core Bluetooth with specific examples - Defining GATT - Defining background behaviors - Testing without HW prototypes - Troubleshooting - App Review
219. ଋɿ31mm ද 4 ද 1 iOSʷBLE Core Bluetooth ϓϩάϥ ϛ ϯά iOSʷBLE Core Bluetooth ϓ ϩ ά ϥ ϛ ϯ ά అ म Ұ দ ଜ ྱ ԝ ử ஶ అमҰʷদଜྱԝ ʹ ஶ Shuichi TSUTSUMI ʷ Reo MATSUMURA iOSʷBLE Core Bluetooth Programming iOSʷBLE 定価：本体4,000円 （税別） Resources • 500 pages about iOS x BLE • Japanese only
220. Resources • Getting Started with Bluetooth Low Energy - Covers large area of BLE • Core Bluetooth Programming Guide - Good to know the overview of Core Bluetooth • Core Bluetooth Framework Reference - Details of Core Bluetooth • Bluetooth Accessory Design Guidelines for Apple Products - For HW side, but helpful also for iOS engineers to know specs or limitations due to HW side such as connection intervals.
221. Resources • WWDC 2012 - Session 703 - Core Bluetooth 101 - Helpful to know about BLE • WWDC 2012 - Session 705 - Advanced Core Bluetooth - Connection interval, Caching, etc… • WWDC 2013 - Session 703 - Core Bluetooth - Retrieving peripherals, State preservation & restoration etc.. - Includes advanced and detailed information • Bluetooth Core Specification by Bluetooth SIG - The official specification / Total 2000 pages…
222. Thank you! Shuichi Tsutsumi - iOS Freelancer • Twitter: @shu223 • GitHub: shu223 • Blog: https://medium.com/@shu223/ • Email: shuichi0526@gmail.com