F14: Team3-Self Driving Car - Optimus Prime

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Grading Criteria

  • How well is Software & Hardware Design described?
  • How well can this report be used to reproduce this project?
  • Code Quality
  • Overall Report Quality:
    • Software Block Diagrams
    • Hardware Block Diagrams
      Schematic Quality
    • Quality of technical challenges and solutions adopted.

Self Driving Car

Abstract

Objectives & Introduction

Team Members & Responsibilities

  • Sensor Controller
    • Team 1: Deepak Yadav & Vinod Pangul
  • Motor Controller
    • Team 2: Naghma Anwar & Shiva Moballegh
  • I/O Unit
    • Team 3: Shreeram Gopalakrishnan & Sreeharsha Paturu Gangadhara
  • Communication Bridge & Android
    • Team 4: Johnny Yam, Kevin Beadle & Chia Pin Tseng
  • Geographical Controller
    • Team 5: Bhushan Gopala Reddy, Ryan Marlin & Rishikesh Nagare
  • Master Controller
    • Team 6: Shashank Tupkar, Bhargava Leepeng Chandra & Preeti Benake

Schedule

Team Schedule

Sl.No Start Date End Date Task Status Actual Completion Date
1 Order RC Car Completed on time
2 Order Other parts(Sensor/LCD/Motor Controller...) Completed
3 9/30/2014 11/25/2014 Master Controller Team task Ongoing
4 10/06/2014 11/15/2014 Sensor Team task Ongoing
5 Motor Controller Team task Ongoing
6 Geographical Controller Team task Ongoing
7 I/O Team task Ongoing
8 Communication Bridge + Android Team task Ongoing
9 Complete project integration  ???
10 Testing-1  ???
11 Testing-2  ???


Master Controller Team Schedule

Week No. Start Date Planned End Date Task Status Actual End Date
1 9/30/2014 10/7/2014
* Implement Basic CAN Hardware to communicate between 2 Controllers
  • Completed
We are able to send a message from Tx over CAN and perform a specific operation at the Rx.
10/7/2014
2 10/7/2014 10/14/2014
* Design CAN Acceptance Filter among different Controllers
* Define and Implement CAN Frame structure for proper communication
  establishment
  • Completed
Only messages with in range of acceptance filter are received, Decided on CAN frame structure using 11-bit frame.
10/11/2014
3 10/14/2014 10/21/2014
* Develop Inter-Controller Communication over CAN
* Test point-to-point and Broadcast message transmission
* Implement a Counter to count and display number of messages 
  • Completed
CAN Communication among multiple boards achieved, Point-to-Point & Broadcast modes are working, Able to display the count on 7-Seg Display on SJOne board.
10/19/2014
4 10/21/2014 10/28/2014
* Layout blueprint for Controller and Module positioning 
* Assemble the RC Car with all the controllers and Modules
* Define the Message List by working with other teams
* Start working on CAN Periodic message structure
  • Completed
RC car design and module assembly is completed. Need some fine tuning for connections. Message list is generated and periodic message implementation started.
10/28/2014
5 10/28/2014 11/04/2014
* Complete CAN Periodic message structure to transmit Broadcast
  messages over CAN and establish controlled communication among
  different controllers 
* Implement Start condition detection and Fetch boot status from
  all controllers and display the status of each controller
  • Completed
Periodic Message Setup done. Able to receive boot status. Need to work on display of status.
11/03/2014
6 11/04/2014 11/11/2014
* Design 'Kill Switch' in co-ordination with Motor Controller team
  and Bridge Controller team
* Develop a 'CAN Bus Crash' detection and reset CAN Bus methodology
* Design Automatic Head Light turn ON/OFF functionality by
  working with Sensors Controller team
  • Completed
Kill Switch implemented through Bridge controller. Head Lights implemented. LCD display of Status achieved.
11/11/2014
7 11/11/2014 11/18/2014
* Implement File Log saving to SD Card at periodic intervals
* Work on Restoring to last known Status if the system crashes while running
* Develop Detection technique if controllers are reaching 'Error State' 
  • Completed
File Log implemented. Error State is partially implemented. Obstacle detection achieved. Needed refinement in Direction control logic. Need to implement reverse logic.
11/18/2014
8 11/18/2014 11/25/2014
* Project Integration and testing Basic Self_Drive Capability of the Car
* Check the Functionality and behavior of all controllers in all the known 
  contexts
* Perform modifications (if any) to eliminate any bugs to make the car work
  seamlessly
* Final Integration of car and testing there after
  
  • Completed
Integration Started. Faced difficulty in synchronization.
11/26/2014
9 11/25/2014 12/02/2014
* Final Integration and testing Self_Drive Capability of the Car   
  • Ongoing
--/--/----


Sensor Team Schedule

Sl.No Start Date End Date Task Status Actual Completion Date
1 10/6/2014 10/18/2014 Order Ultra Sonic Sensors Completed [Got two sensors (front and back), 2 more (front right & left) to order ->Completed.] 10/19/2014
2 10/9/2014 10/9/2014 Sensor Data Sheet review with the team Completed 10/9/2014
3 10/9/2014 10/16/2104 Sensor code development Completed (Implementing filter (HW/SW) to get more accurate data ->(Done). Add logic to get the rest of the three sensor(front right/left and back data)->(Done) (Note: Delayed due to the implementation of CAN structure and calibration of IR sensor) 10/21/2014
4 10/22/2014 10/25/2014 Sensor software testing Ongoing
5 10/25/2014 10/28/2014 Sensor real time testing Ongoing
6 10/13/2014 10/15/2014 Light sensor code Development Completed 10/14/2014
7 10/13/2014 10/15/2014 Accelerometer sensor code Development to detect tilt Completed 10/14/2014
8 10/15/2014 10/15/2014 Light Sensor and Accelerometer Testing Completed 10/15/2014
9 10/29/2014 10/31/2014 Battery status controller circuit Design Ongoing
10 11/01/2014 11/02/2014 Battery status-circuit Testing
11 11/03/2014 11/04/2014 Common Communication SW code implementation and testing
11 11/04/2014 11/09/2014 Complete Hardware testing-1
12 11/10/2014 11/15/2014 Complete Hardware testing-2


Motor Controller Team Schedule

Week No. Start Date Planned End Date Task Status Actual End Date
1 9/30/2014 10/7/2014
* Study SJOne board's motor controller concepts and PWM
  • Completed
Very simple code. Just two lines. Set the frequency. Set the duty cycle.
10/7/2014
2 10/7/2014 10/14/2014
* Open up RC Car's motor and servo connections 
* Study the Electronic Speed Control's functions
  • Completed
Motor and Servo operate on the same frequency
ESC needs calibration each time it is switched on. Need to find a solution for this.
10/11/2014
3 10/14/2014 10/21/2014
* Define the duty cycles for proper motor and servo signals 
  • Completed
Using trial and error, figured out the duty cycle for constant speed and turns
10/19/2014
4 10/21/2014 10/28/2014
* Add CAN frame structure to the motor functions 
* Test for communication between motors and sensors for prototype demo 
* Define the Message List by working with other teams
  • Completed
11/04/2014
5 10/28/2014 11/04/2014
* Start working on CAN Periodic message structure
* Start looking for speed sensors
  • Completed
Bought magnetic speed sensor from Traxxas telemetry
from local RC Car store
11/04/2014
6 11/04/2014 11/11/2014
* Attach speed sensors to the motor
* Test CAN communication between motor controller and other controllers
  • Completed
Speed sensors attached
11/11/2014
7 11/11/2014 11/18/2014
* Work on speed sensors. Figure out the way to send sensor data to master controller. 
* Test for proper and accurate CAN communication 
  • Completed
11/18/2014
8 11/18/2014 11/25/2014
* Project Integration and testing basic self drive capability of the car
* Check the functionality and behavior of the motor controller in all the known 
  contexts
* Perform modifications (if any) to eliminate any bugs to make the motor work
  seamlessly
* Final Integration of car and testing there after
  
  • Ongoing
--/--/----


Geographical Team Schedule

Sl.No Start Date End Date Task Status Actual Completion Date
1 10/4/2014 10/13/2014 Research and Order GPS module Received GPS module 10/7/2014
2 10/7/2014 10/18/2014 Interface GPS module with LPC1758 Finished 10/17/14
3 10/14/2014 10/18/2014 Receive Compass module from Preet Received 10/9/2014
4 10/18/2014 11/4/2014 Parse GPS data and setup constructs to send appropriate data Ongoing
5 10/14/2014 10/18/2014 Interface the Compass Module Finished 10/16/2014
6 10/25/2014 11/4/2014 Calibration of Compass Code completed. Need to test using the car --/--/----
7 11/4/2014 11/11/2014 Integrate GPS and Compass data Ongoing
8 10/25/2014 11/09/2014 Testing and mapping of GPS co-ordinates Ongoing
9 11/18/2014 11/25/2014 Final integration and testing

IO Team Schedule

Sl.No Start Date End Date Task Status Actual Completion Date
1 10/7/2014 10/13/2014 Research and Order LCD Display Ordered LCD Display 10/13/2014
2 10/14/2014 10/21/2014 Interfacing LCD Display with LPC1758 Completed 10/21/2014
3 10/21/2014 10/28/2014 Implementing CAN structure with LCD tasks. Completed 11/30/2014
4 10/28/2014 11/04/2014 Subscribe data from motor, sensor and GPS controller,display it on LCD. Ongoing
5 11/04/2014 11/11/2014 Setup hardware and write code for START, STOP and Headlight buttons. TBD
6 11/11/2014 11/18/2014 Testing and mounting hardware on car. TBD
7 11/18/2014 11/25/2014 Final Testing TBD


Communication Bridge & Android Team Schedule

Sl.No Start Date Planned End Date Task Status Actual End Date
1 9/30/2014 9/30/2014 Obtain Bluetooth Module (already had one) Done 9/30/2014
2 9/30/2014 10/14/2014 Develop Basic Android App with Bluetooth Sensor Communication Done 10/7/2014
3 10/11/2014 10/14/2014 Interface Bluetooth Module with SJSU Dev Board Done 10/11/2014
4 10/12/2014 10/19/2014 Be able to send bi-directional arbitrary messages between Android App and Dev Board via Bluetooth Done 10/14/2014
5 10/14/2014 11/21/2014 Subscribe to all CAN messages and dump all of them via Bluetooth to Android App or web interface Done 11/24/2014
6 10/14/2014 11/21/2014 Ajax & Websocket server remote structure Done 11/01/2014
7 10/14/2014 11/21/2014 Be able to input GPS coordinates through either (or both) Android App and web interface and send through Bluetooth then CAN bus Done 11/24/2014
8 10/21/2014 11/24/2014 Android App and webpage GUI enhancements (Google Maps, Google Drive) Done 11/24/2014
9 10/21/2014 11/30/2014 Data visualization (status, compass, speed, location,....) On going TBD

Parts List & Cost

Item# Part Desciption Vendor Part Number Qty Cost
1 RC Car Amazon.com Traxxas 37076 Rustler VXL 1 $380.57
2 RC Car Battery Amazon.com Traxxas 2926 NiMH 8.4V Hump 3000mAh TRA Connector 2 $67.38
3 CAN Transceiver Texas Instrument SN65HVD232D 15 $75.00
4 Assembly Components Amazon.com, Anchor & HSC PCBs, Mechnical & Electical Components NA $110.80
5 Power Supply Pololu.com 6V Battery, 5V Regulator 1 $34.85
6 Sonar sensor Maxbotix LV-MaxSonar-EZ1 MB1010 2 $66.55
7 Sonar sensor Given by Preet LV-MaxSonar-EZ1 MB1010 1 Free
8 Compass Module Given by Preet HoneyWell: HMC 6352 1 Free
9 LCD Display New Haven NHD-0216B3Z-FL-GBW-V3-ND 1 $$$.$$
10 Battery Status Amazon.com Dc 4.0-30v LED Digital Display Voltage Meter 1 $6.91
Total Cost $$$.$$

Design & Implementation

Controller Communication Table

Controllers
Controller ID Controller Type
0x01 Master Controller
0x02 Motor Controller
0x03 Sensor Controller
0x04 Geographical Controller
0x05 IO Controller
0x06 Bridge Controller
Common Communication Table
Message Number Purpose / Data layout
0x101 Get version and boot info
0x102 Get general info
0x103 Synchronize (set) time:
byte [0-3] : System time
0x201
byte [0-3] : Version Info
byte [4-7] : boot timestamp
0x202
byte [0-3] : Current time
byte [4]   : CPU usage %
Subscription Rate Info
Byte 0 Effect
0 Off
1 1Hz
5 5Hz
10 10Hz
20 20Hz
50 50Hz
Any other value Invalid date rate


Master Controller Communication Table
Message Number Purpose Data Byte Pattern
0x101 Ask for Boot and Version Info. of all Controllers
Byte[0]: Send a '1'
0x103 Sync. Master System Time on all Controllers
Byte[0-3]: System Time [HH:MM:SS]
0x201 Master Gets Status Update from all controllers
Byte[0]: Boot Status
Byte[1]: Version Info.
0x203 Master Gets current Time from all Controllers
Byte[0-3]: Time in [HH:MM:SS]
0x301 Master Enable Main UI in Android
Byte[0]: Send a '1'
0x302 Master set GPS Destination on Geo Controller
Byte[0-3]: Latitude Value
Byte[4-7]: Longitude Value
0x303 Master set Longitude Way-Points on Geo
bytes [0-1] : Total Way-Points count
bytes [2-3] : Way-Point index
bytes [4-7] : Longitude(float)
0x304 Master set Latitude Way-Points on Geo
bytes [0-1] : Total Way-Points count
bytes [2-3] : Way-Point index
bytes [4-7] : Latitude(float)
0x305 Master Send GPS FIX Ack to Bridge
Byte[0]: Send a value '1'
0x306 Master Send Dest. Reached Ack to Bridge
Byte[0]: Send a Value '1' 
0x500 Display Boot and Version Info. on LCD
Byte[0]: Boot Status Response
Byte[1]: Version Info.
0x501 Display Controllers Time on LCD
Byte[0-3]: Time in [HH:MM:SS]
0x502 Display Destination Has Reached
Byte[0]: Send a '1'
0x503 Master Set Speed and Direction of Motor
Byte[0]: LEFT/RIGHT (or) FRONT/BACK command
0x504 Display Speed of Motor on LCD
Byte[0]: Speed Value
0x505 Display GPS and Compass values on LCD
Byte[0-1]: New Degree to Head
Byte[2-3]: Dist to Destination
Byte[4-5]: Current Degree value
0x506 Display Sensor Values on LCD
Byte [0]: Front sensor value in inches
Byte [1]: Front Left sensor value in inches
Byte [2]: Front Right sensor value in inches
Byte [3]: Back sensor value in inches
0x507 Display Battery Status on LCD
Byte[0]: Battery Status Value


Motor Controller Communication Table
Message Number Purpose Data layout
0x508 Speed Sensor Data
byte [0] : Speed sensor value in rpm
0x509 Vehicle Direction/Movement Data
byte [0] : Movement Control
     0x1 : Forward
     0x2 : Reverse
     0x3 : Stop
byte [1] : Steering Control
     0x1 : Left
     0x2 : Right
     0x3 : Straight


Sensor Controller Communication Table
Message Number Purpose Data layout
0x510 Front/Back Range Sensor Data
byte [0] : Front sensor value in inches
byte [1] : Front Left sensor value in inches
byte [2] : Front Right sensor value in inches
byte [3] : Back sensor value in inches
byte [4] : Back Left sensor value in inches
byte [5] : Back Right sensor value in inches
0x511 Accelerometer Sensor Data
byte [0] : X axis Value
byte [1] : Y axis Value
byte [2] : Z axis Value 
0x512 Light Sensor Data
byte [0] : Light sensor value
0x513 Battery Status Data
byte [0] : Battery status value
0x514 Motor command Data
byte [0] : Motor command value


GPS Controller Communication Table
Message Number Purpose Data layout
0x518 Send GPS Data to Master
 byte [0 - 1] : New Degree
 byte [2 - 3] : Distance
 byte [3 - 4] : Current Degree
0x519 Send GPS FIX ACK to Master
 byte[0]: Send a '1'
0x52A Send Destination Reached ACK to master
 byte[0]: Send a '1'


IO Communication Table
Message Number Purpose Data layout
0x520 Subscribe to Sensor data bytes [0-5] : Sensor Value in Inches
0x521 Subscribe to Motor data bytes [0-2] : Vehicle Direction
0x522 Subscribe to Compass Data bytes [0] : Compass Data in degrees
0x523 Subscribe to Battery Status bytes [0] : Battery Status Value


Communication Bridge Communication Table
Message Number Purpose Data layout
0x528 Set Car Speed (Kill Switch) - temporary allow for other non-zero value for demo byte[0] - speed value
0x529 Destination GPS location

bytes [0-3] : latitude (float) bytes [4-7] : longitude (float)

0x52A Turn to degree

bytes [0-3] : degree(float)

0x52B Way points longitude
bytes [0-1] :total waypoints count
bytes [2-3] :waypoint index
bytes [4-7] : longitude(float)
0x52C Way points latitude
bytes [0-1] :total waypoints count
bytes [2-3] :waypoint index
bytes [4-7] : latitude(float)
0x52D remote status (ie. Android connection status)
bytes [0]=>
0:disconnected(passive send)
1:on disconnect(active)
2:connected(passive)
3:on connect(active)
0xFF:error(active/passive)

Hardware Design

Communication Bridge + Android

  • In order to facilitate wireless communication between the SJSU One Board and a Android device, a Bluetooth Bee module is used. This module was chosen because it can connect and mount directly onto the SJSU One Board's XBee breakout socket.
  • The Bluetooth Bee is a Serial Profile Port (SPP) Bluetooth interface that connects with the SJSU development board's UART3.
Bluetooth Bee Module

Hardware Interface

Communication Bridge + Android

The relevant pin connectivity table between the Bluetooth Bee module and the SJSU One Development Board is shown below:

Communication Bridge Pin Connectivity Table
Description Bluetooth Bee Port SJSU Development Board Port
3.3V Supply Voltage 3V3 3V3
Ground GND GND
Channel 1 TX RX
Channel 2 RX TX

The Bluetooth Bee Module interfaces with an Android device through Bluetooth.

Software Design

Communication Bridge + Android Interface

  • The bridge controller and Android APP work as routers

Bridge Controller

  • Bridge controller translates CAN bus data into plain text and send it to android platform
  • The Bridge controller is comprised of the SJSU Development Board with the Bluetooth Bee Module.
  • The Bluetooth Bee Module can be configured by writing to UART3 specific commands as specified in the Bluetooth Bee Seeedstudio Wiki.
  • The Bluetooth Bee Module was configured as SLAVE MODE via the command: \r\n+STWMOD=0\r\n
  • The Bluetooth device name was set to "Yam_BluetoothBee" using the command: \r\n+STNA=BluetoothBee\r\n
  • Allowing other devices to connect to the Bluetooth Module was enabled using the command: \r\n+STOAUT=1\r\n
  • Finally the Bluetooth Bee Module started broadcasting/inquiring to connect to another device using the command: \r\n+INQ=1\r\n
  • There are many other commands, such as to change the default pincode value, but they were not used for this project.


Bridge framework

Android Controller

  • Android platform receives the text data from bridge controller, then, transmit the data through ajax or websocket
  • External controller could be any TCP accessible device (simple pebble watch program (20 lines) are used to control start and stop)
  • One administrator(control and receive), multiple observers(only receive)


Bridge framework
cross platform


Intro
Intro
Intro
Intro


Sensors : Sonar Sensors + IR Sensors

A) Sonar Sensor:

  • The ultrasonic sensors are in air, non-contact object detection and ranging sensors that detect objects within an area.
  • We are using 3 such sensors in front to get wide angle vision for the car.
  • Ultrasonic sensors use high frequency sound to detect and localize objects in a variety of environments. Ultrasonic sensors measure the time of flight for sound

that has been transmitted to and reflected back from nearby objects. Based upon the time of flight, the sensor then outputs a range reading.

B) Infrared Sensor (IR):

  • The basic principle of operation of an infrared sensor is based on infrared light that is reflected when its hits an an obstacle. An IR receiver captures

the reflected light and the voltage are measured based on the amount of light received.

  • IR Sensors have 3 pins to connect to SJOne Board:


1) Ground (GND)
2) +Vcc (5 V)
3) Vo (ADC-4 is on P1.30, select this as ADC0.4)

IR Sensor Block Diagram
Calibrated voltage output with distance

I/O Unit:

  • The IO Control Unit manages the LCD Display, switch to start and stop the car
  • It receives CAN data from the Master controller and accordingly processes to display on the LCD through UART
  • The 7 segment LED displays the CPU usage

LCD Display

  • The LCD Display is placed on the rear side of our RC Car
  • It displays the sensor and GPS values in real time.
LCD Initialization


Motor Controller

Hardware Design

Anatomy of The Rustler

Parts and their functions
Velineon 3500 Brushless Motor

Motor : Our RC car came with Velineon 3500 Brushless Motor. One of the main drawbacks of brushless motor is that it requires a speed controller to change the field polarity. We can't just give power to the motor directly and expect it to go. We can almost consider the controller as an integral part of the motor itself.

Velineon VXL-3s ESC

ESC : Electronic speed controller was the trickiest part to deal with, since it comes with a previously programmed microcontroller inside it. It needs callibration, for which you need to refer to the user manual. An electronic speed controller basically controls the power given to the motor. Our RC car came with VXL-3s ESC, which accepted 100 Hz PWM input signal whose duty cycle varied from 10% to 20%. When supplied with a 15% duty cycle at 100 Hz, the ESC responded by turning off the motor attached to its output.

Steering Servo : Our RC car was equipped with a digital servo (Traxxas part #2075) for steering control. It does not require an ESC to operate. We can give PWM signal directly to the servo from the SJOne board. The servo accepted 100 Hz PWM input signal whose duty cycle varied from 10% to 20%, where 10% represents extreme right turn and 20% represents extreme left turn.
Steering Servo

Speed Sensor : To measure the RPM and speed of our car, we used the speed sensor provided by Traxxas Telemetry. This magnetic speed sensor worked on Hall effect. To learn more about Hall effect sensors, you can click on this wikipedia article. Since the sensor was provided by the same brand of our car, the installation was quick and easy. Here's a reference video on how to attach magnetic speed sensor to the RC car.

Traxxas 7-Cell 8.4V NiMH Battery Pack

Battery : We used 7 Cell NiMH (Nickel-Metal Hydride) battery pack for our car but would recommend others to use Lipo (Lithium Polymer) batteries instead. NiMH batteries tend to discharge very quickly. Also we realized later that since this car was made for racing purpose, its speed was too fast for our project. We reduced the voltage by removing 2 cells from the 7 cell battery pack. So, go for the 5 cell battery pack instead. A Traxxas EZ-Peak Charger would help a lot while doing testing.

Hardware Interface

Motor and Servo Interface
Speed Sensor Interface

Software Design

Testing & Technical Challenges

Sensor Controller

  • Front and Back Sensors Controller
    • Describe how you tested the Sensors and calibration of the sensors

Mention the Issues you faced and also the solutions you'll used to overcome the problem.

Motor Controller

  • Motor Controller
    • Describe how you tested the motors. Explain the speed control methods used and difficulties you faced during calibration.

Mention the Issues you faced and also the solutions you'll used to overcome the problem.

I/O Controller

  • I/O Testing
    • Describe how you tested the LCD. Problems faced during testing.

Mention the Issues you faced and also the solutions you'll used to overcome the problem.

Communication Bridge

TESTs

  • 100000 message(20bytes per message) Bluetooth transmission between board and android under 200fps with range <5m
    • 100% success

ISSUE

  • 3G network server could not be access(3G network is used for long range communication)
    • might use google sheet or external server to communicate

Geographical Controller

  • Geographical Controller
    • Describe how you tested the Compass and explain how did you manage to achieve the maximum accuracy.

Mention the Issues you faced and also the solutions you'll used to overcome the problem.

Master Controller

  • Master Controller functions as the brain of car. The only challenge was integrating the master controller with the remaining five controllers.
    • Describe how you tested the Master Controller and problems faced while integrating it with all the other controllers.

Mention the Issues you faced and also the solutions you'll used to overcome the problem.

Conclusion

Project Video

Project Source Code

References

Acknowledgement

References Used

http://www.ti.com/product/sn65hvd232

http://www.socialledge.com/sjsu/index.php?title=Self-driving_Car

http://www.nxp.com/documents/user_manual/UM10360.pdf

http://www.socialledge.com/sjsu/images/d/de/2012SJOneBoardSchematic.pdf

http://www.maxbotix.com/documents/MB1010_Datasheet.pdf

http://www.sharpsma.com/webfm_send/1208

https://www.sparkfun.com/datasheets/Components/HMC6352.pdf

http://www.seeedstudio.com/wiki/Bluetooth_Bee

Appendix