Introduction: BLE Based Reconfigurable Sensor Network & Distributed Control System

Picture of BLE Based Reconfigurable  Sensor Network & Distributed Control System

We are presenting before you a Bluetooth Low Energy ( BLE ) based Reconfigurable Sensor Network & Distributed Control System which you can adopt for multiple purposes such as smart home automation, drone & glider testing, integrated structures monitoring etc...

This system is implemented using Intel Curie module as the brain of system. Intel’s Curie module is a tiny system-on a-chip (SoC) based on the Intel Quark SE.Curie is equipped with a 32-bit Intel Quark SoC with 384kB of flash memory and 80kB SRAM. It comes in an easy-to-integrate package with a six-axis combo accelerometer and gyroscope sensor to enable movement tracking and gesture recognition. Curie also features a digital sensor hub with a pattern-matching accelerator, battery charging circuits. The device uses Bluetooth low energy for communications.

Case Study

Rockets are an engineering marvel in human history. It is a group of various subsystems. It is very prone to accidents. So it need very close monitoring of these subsystems.For that, typically about 2500+ individual transducers are distributed throughout the rocket. These sensors, subsystems and harness weighs about 50 Kg, involves huge amount of skilled labour, time for testing etc…

Limitation of Existing System

  • Different Systems are hardwired
  • Limited Flexibility & Testability
  • EMI problems when measuring Subtle signals
  • Very High Integration & Check-out Time
  • Misinterpretation of Wiring Diagram
  • Huge Harness Weight & Complexity
  • Multipoint ground loop & signal Integrity Issues

Advantages of Proposed System

  • Harness mass reduction
  • Simpler Integration
  • Elimination of Test & Debug Connectors
  • Allows Subsystems to join/leave network at any time
  • Self Healing Network Implementation
  • Reduced Assembly, Integration & Testing Time
  • SWaP CR ( Size, Weight and Power savings less Cost & high Reliability)

Step 1: Wireless Sensor Network in Action

Working Video of Sensor Network System

Step 2: Wireless Sensor Network : Overview

Picture of  Wireless Sensor Network  : Overview

Intel Curie Based :

  • IMU Nodes for navigation
  • Sensor Nodes for Sensing
  • Control Actuator Nodes for Thrust Vector Control
  • Central Node acting as gateway to existing System Storage & Display Node

Step 3: IMU (Inertial Measurement Unit) Node

Picture of IMU (Inertial Measurement Unit) Node
  • IMU Node contains all the required hardware such as 3-axis accelerometer, 3-axis gyro and 3-axis magnetometer for a 9-DOF (Degrees of Freedom) Inertial measurement.
  • Included GPS can used for aided navigation application.
  • Sensor data fusion is employed for gyro drift, accelerometer/GPS error Compensation.
  • Depending on the firmware this module can act as :

▪ 6-axis IMU

▪ 3-axis Magnetometer

▪ 66 channel High Accuracy GPS Module with fast TTFT

Step 4: IMU Node Fabrication

Picture of IMU Node Fabrication

IMU Node is wired with other sensors on Perf-Board and is Enclosed in the custom 3D Printed Enclosure.

Hot Glue is used for securing all components to the enclosure

Step 5: IMU Node 3D Design Files

Picture of IMU Node 3D Design Files

Solid-works software is used to model and design all the parts. All files required for 3D printing is given here.

Step 6: IMU Node 6 Axis Motion Sensor Schematic, Code & Demo

Picture of IMU Node 6 Axis Motion Sensor Schematic, Code & Demo

Arduino code is attached & Result of working is Showed on nRF Connect android app from Nordiac Semiconductor ( available on Play store )


Step 7: 3 Axis Magnetometer Schematic, Code & Demo

Picture of 3 Axis Magnetometer Schematic, Code & Demo

Arduino code is attached & Result of working is Showed on nRF Connect android app from Nordiac Semiconductor ( available on Play store )

Step 8: GPS Node Demo & Arduino Schematic, Source Code

Picture of GPS Node Demo & Arduino Schematic, Source Code

Arduino code is attached & Result of working is Showed on nRF Connect android app from Nordiac Semiconductor ( available on Play store )

Step 9: Sensor Node

Picture of Sensor Node

  • Sensor Node is built around Arduino 101 BoardIt acts as a scalable multi-parameter monitoring Node
  • Basic Node Consists of Pressure, temperature & humidity sensor
  • Basic Node has the capability to attach following sensors:

▪ An Acoustic Pick-up sensor

▪ A Strain-gauge based on FSR ( Force Sensitive resistor )

▪ A high precision Shock sensor

Step 10: Sensor Node Schematics

Picture of Sensor Node Schematics

Schematics & Wiring Diagram of Sensor Node is given here.

Step 11: Sensor Node Demo & Source Code

Picture of Sensor Node Demo & Source Code

Arduino code is attached & Result of working is Showed on nRF Connect android app from Nordiac Semiconductor ( available on Play store )

Step 12: Sensor Node 3D Design Files

Picture of Sensor Node 3D Design Files

Solid-works software is used to model and design all the parts. All files required for 3D printing is given here.

Step 13: Actuator Node

Picture of Actuator Node

Actuator Node is built around an Arduino-101 with two Servo motor based linear actuators. Both actuators are attached to the Nozzle for Thrust vector Controlling and thus forming an Engine Gimbal Control. Actuator has a BLE Service and its characteristics can be written from central node.

Step 14: Actuator Node Assembly

Picture of Actuator Node Assembly

Different joints and linkages are designed and 3D Printed.

M3 nut & bolt along with washers are used for assembly.

Step 15: Actuator Node Code & Schematic

Picture of Actuator Node Code & Schematic

Schematic & Source-code of actuator node is given here.

Step 16: Actuator Node 3D Design Files

Picture of Actuator Node 3D Design Files

Solid-works software is used to model and design all the parts. All files required for 3D printing is given here.

Step 17: Central Node

Picture of Central Node

Central Node handles the task of data acquisition from all sensor nodes and is also responsible for updating the actuator node variables. The Central node also has the capability to analyse the incoming data for any errors.The Nodes work on the concept of publish/subscribe model. Each Sensor node & actuator node has a BLE service and associated characteristics which can be read or written into.All nodes will be in the advertisement mode initially.Central node connects to each nodes sequentially and will read / write the required services & characteristics.

Step 18: Central Node Internals

Picture of Central Node Internals

Central node is for exploring the sensor and actuator node services and characteristics and posting the values to UART link. Source Code & schematic is given here.

Step 19: Storage & Display Node

Picture of Storage & Display Node

Storage & Display Node does the task of receiving the data from central node via a UART link and It stores the data in a micro-SD based card and uses the On-board TFT display to show the parameters and connection status in near real time.

Step 20: Display Node 3D Printing

Picture of Display Node 3D Printing

Rapid Prototyping is the technical term for this kind of additive manufacturing process and 3D printing is the colloquial term for the same so that many people can grasp this technology easily. A not so accurate yet commonly perceived difference between Rapid Prototyping and 3D printing is that Rapid Prototyping is industrial level and 3D printing is consumer level additive manufacturing technology.

Step 21: Comparison With Existing System Scenario

Picture of Comparison With Existing System Scenario

Existing Instrumentation and Control System requires extensive wiring with lot of connectors and are error prone .

The Wireless Sensor Network offers a drop-in plug & play elegant solution

Step 22: What It Does

Picture of What It Does

Altogether It does the Task of remote multi-parameter monitoring and control in a launch vehicle/satellite scenario without the need of bulky harness and has a huge impact by the reduction of amount of effort & time involved in assembly and integration of launch vehicles / satellites

Step 23: Grove Kit Experimentation

Picture of Grove Kit Experimentation

Grove Starter Kit Plus - IoT Edition is used for initial prototyping

No soldering, no jumper wires, no jitters. Simple, easy, and fast. This is how this kit gonna make you feel when you use it to make your IoT devices - a totally enjoyable making process. The Grove Base Shield in the kit can works on a lot of Arduino compatible development boards including the Intel Edison for Arduino, LinkIt One, and Genuino 101 etc. Beyond the Grove Shield is a bunch of Grove sensors and actuators with build-in Grove interfaces, makes your prototyping faster and easier. Simply plug in the modules and you are ready to create.

Grove Kit Link

Step 24: Intel Edison Based Checkout System

Picture of Intel Edison Based Checkout System

Intel Edison based BLE Central Demo is used to verify the BLE services and characteristics associated with each sensor nodes.

Also a BLE Sensor Tag from BroadCom is tested for working

Step 25: System Prototyping on Bread Board

Picture of System Prototyping on Bread Board

Breadboards are one of the most fundamental pieces when learning how to build circuits Prototyping is the process of testing out an idea by creating a preliminary model from which other forms are developed or copied, and it is one of the most common uses for breadboards. If you aren’t sure how a circuit will react under a given set of parameters, it’s best to build a prototype and test it out.For those new to electronics and circuits, breadboards are often the best place to start. That is the real beauty of breadboards–they can house both the simplest circuit as well as very complex circuits.

Step 26: How We Built It

Picture of How We Built It

Rapid prototyping Techniques such as 3D printing is used extensively in the development of Prototypes. Initially all circuits are designed and tested in breadboards before final integration. NRF Connect App is used to verify the Sensor Nodes Services and Characteristics UUIDs.

Step 27: Challenges We Ran Into

Picture of Challenges We Ran Into

Design and development of the demo model of the linear actuator for Thrust Vector Controlling as it involves complex mechanical assembly and linkages

Words from Mechanical System Design Task Team Head : Ani Sam Varghese

I worked on the design and fabrication of the system. I custom designed and 3D printed the enclosures for the controller, casing and mound for all sensors, also the thrust vector control mechanism for the nozzle. The major challenge was to make each design as small as possible while maintaining the structural integrity of the design, functionality of the model and the visual appearance of the design. I made a locking mechanism for attaching the body and cap of the boxes for the controllers so that we can eliminate the use of Nuts, Bolts and other types of fasteners. This enabled us to easily open and close the enclosure during the development process without wasting precious time. Another challenge was the thrust vector controlling system. For that, I had to design a system that allows slight motions in 2 angles and a small spin for the easy movement of the nozzle.

Step 28: Accomplishments That I'm Proud Of

Within the time bound we are able complete a functional prototype of the idea conceived by us and we successfully incorporated the Intel Curie Chip for our project

Step 29: What's Next for Curie Wireless Sensor Network

  • Including more sensors and actuators
  • Dual redundancy in central node
  • Fail safe communication
  • On-Board Autonomy Feature

Comments

DIY Hacks and How Tos (author)2017-09-09

Awesome project. You have definitely got my vote. Good luck in all the contests.

Thank you for your support