A network room controller will monitor the temperature and humidity of a room and also operate as a door controller. This device would be used in server and mechanical rooms that need to be monitored and secured.
The network controllers could be installed on a campus, in a data center, or in a small business to provide security and environmental monitoring for systems. The controllers will find the campus controller server via a simple DNS lookup. Once provisioned by an administrator, they are part of the system. The controller server software will run a standard lamp server stack, so it is deployable in many environments.
During normal operation, the device will update sensor readings to the server. The server software will monitor the updates and notify employees when the sensors return values out of range. The box will also listen for an access card to be scanned by a wiegand proximity card reader. When a card is scanned, the number will be sent to the server. if the user is authorized, a relay or darlington transistor will power an electric strike allowing the door to open. The device communicates to the server using standard web protocols.
The devices will be administered via a web interface on the central server. Sensor boundaries and access cards may be added to the system in an administrative interface. A mobile view will allow alerts to be viewed on a mobile device.
Building fire and security systems often use 12VDC power, there are a variety of UL listed enclosures that already provide regulated 12V power from a 120VAC input. Some enclosures provide room for a backup 12V SLA that will continue to power the controller when the main power cuts out. The final board may mount into one of these enclosures.
The temperature sensor will be able to be connected directly to the board either wired or wirelessly. The wireless sensors will communicate with a coordinator device which can be used as a stand alone product that can communicate with the server to update the temperatures.
Environmental monitoring and access control systems are present in many different buildings. These systems monitor temperature for food and equipment safety, and comfort. Access control systems secure buildings and campuses by only allowing designated users into secured areas. These products tend to be be parts of two discrete systems today. The new device will combine these systems into one unit that can serve at both capacities. This simplification reduces manufacturing costs by sharing resources between devices. The design document below describes system and subsystem requirements for device design and manufacturing.
An alternative design would be to design a simpler system. For example, instead of making the sensors readable from the internet we could have it so that all the sensors would have to be read from an LCD that is connected right to the beaglebone. The drawback of this design is that we would not be able to monitor the temperatures from multiple locations. In addition, we would not be able to control the door access system remotely. This design would be much easier because we would not have to worry about servers or web design. If we went with this design we could just hardwire the sensors to the beaglebone and then write a program that takes turns reading each temperature sensor. In addition, the door access system could also be hardwired to the beaglebone and then we would have all the information for who has access to each door stored in the beaglebone. However, this design would be more complicated in regard to the fact that we would have to write extra code in order to have an LCD screen to interface with the beaglebone
Designing our system to do both the temperature monitoring and door access might be a little too much. As a result, an alternative design idea would be to build a system that does only the temperature sensing. We could still use the server and web interface however we could just do away with the door access system. In this new system we will still use the beaglebone to read all the data from the temperature sensors. In addition, we will design a website that the user will be able to access and read the temperatures of each sensor. By doing away with the door access system we will have extra time where we could have the temperature sensors communicate with the beaglebone by either a wire or wireless. The wireless communicating would be more convenient because we will be able to put the sensors in positions we might not be able to run wire too, however we will still have to power the sensors.
Using a beaglebone to compute our data will make it easier to connect to the internet. However, the beaglebone costs $45 which can be pricy. For example, is a customer owns 15 restaurants and wants to monitor the temperature of each restaurants freezer/cooler buying 15 beaglebones would start getting expensive. As a result, an alternative design could be to use a cheap microcontroller in place of the beaglebone. Since the beaglebone has a Ethernet jack on board it would be fairly simple to connect to the internet, and if we use a microcontroller it would more difficult to transmit our data to a server. In addition, making our sensors wireless would be more difficult with the microcontroller because we can connect a Wifi adapter directly to the beaglebone. Since, the beaglebone does increase the cost of our system we need to seriously consider this design for such cases as described above.
# | Criteria | Idea 1 | Idea 2 | Idea 3 |
---|---|---|---|---|
1 | Contribution that this design approach will make to your ECE education (+3) | 5 | 4 | 6 |
2 | Your group’s technical knowledge about the design alternative (+2) | 5 | 4 | 3 |
3 | Cost to consumer (+1) | 2 | 3 | 4 |
4 | Availability of parts required | 1 | 3 | 2 |
5 | Time needed to complete design and development | 3 | 2 | 1 |
6 | Development cost (what each team member will need to spend) | 1 | 3 | 2 |
7 | Ease of satisfying the previously-defined technical specifications | 2 | 3 | 1 |
8 | Availability of any required datasheets, application notes or development kits | 3 | 2 | 1 |
9 | Ability to manufacture | 3 | 2 | 1 |
10 | Compliance with regulations or standards issues that will need to be addressed | 2 | 1 | 1 |
11 | How attractive this design method will look on your resume | 2 | 1 | 3 |
12 | Ease of product use | 3 | 2 | 1 |
13 | Suitability for presentation at the Senior Design Expo | 3 | 2 | 1 |
Total | 35 | 32 | 27 |
Week | Project Phase | Task | Responsibility |
---|---|---|---|
Beginning of winter break | Ordering Parts | ordering and receiving parts | Karl |
Winter Break | Demo Construction | Create A door with electric strike plate | Michael |
Week 1 - 2 | Prototype Construction | Create working prototype | Aissar and Karl |
Week 3 | Prototype Construction | Write drivers for Weigand Reader | Akeem |
Week 4 | Prototype Construction | Write drivers for temperature sensors | Akeem |
Week 5 | Evaluate Wireless Modules | Purchase and evaluate wireless modules | Michael |
Week 6 | Wireless Prototype | Write software for prototype wireless nodes | Michael |
Week 7 | Server Evaluation | Evaluate software frameworks for web front and backends | Karl |
Week 8 | Security Backend | Write code for security backend | Karl |
Week 9 | Environmental Backend | Write code for environmental backend | Karl |
Week 10 | Demo Construction | Create A door with electric strike plate | Michael |
Week 11 | Demo Construction | Create A door with electric strike plate | Michael |
Week 12 | Testing | Bring everything together for testing | Aissar |
Week 13 | Testing | Continue improving code so everything can talk to each other | Karl and Aissar |
Week 14 | Debugging and Testing | Continue improving code so everything can talk to each other | Group |
Week 15 | Web Improvements | Complete web backend and interface | Karl |
Week 16 | Final Testing | Complete final report and create display for Expo | Group |
The controllers will have diagnostic LEDs that will indicate valid communication to the management server. A green LED will indicate that there is valid communication, a red led will indicate that there is bad or no communication.
The web interface, hosted by a central server, will allow remote configuration, monitoring, and control of the system. This interface can be hosted on the local network, or sit on the public internet. This option is left to the end user.
The interface will scale between smartphone, tablet, and desktop browsers to allow a variety of users and devices to connect to the system. Standard web authentication and security methods will be used to secure controllers, doors, and the data logged. Interface traffic will be encrypted via https.
The wireless sensors will have an interface of their own. The coordinator will have 2x16 LCD display with 5 push buttons. The display will give the user the ability to monitor the temperatures of the wireless sensors and the ability to add/subtract sensors from the network.
User | Door | Access Time | Status |
---|---|---|---|
Akeem | Front Door | Thu May 1 23:54:46 2014 | Access Denied |
Karl | Front Door | Thu May 1 23:54:41 2014 | Access Granted |
Karl | Front Door | Thu May 1 23:54:39 2014 | Access Granted |
Mike | Front Door | Mon Apr 21 01:47:10 2014 | Access Denied |
Mike | Front Door | Mon Apr 21 01:47:06 2014 | Access Denied |
The design was simplified by removing relays. Darlington drivers with built in kick-back protection diodes were used to operate the solenoids within the electric strike plates.
The implementation of Zigbee modules enabled the use of wireless sensing nodes. These nodes operated in a low power mode to send temperature updates to the server on a user specified interval.
Economic: The only economic issue that might affected the manufacturer of this design would be the cost of a wafer when making each test and final PCB. Since the amount of components one can fit on a wafer continually increases by Moore’s law, the availability of funds to supply silicon wafers will be an important factor for the development stage of the design.
Environmental: The only problems will arise from the disposal of PCB’s and the battery/ power supply. This project can be considered a green design since there are no major impacts to the environment. During the testing phase, the solder will have traces of lead but during a large scale manufacturing process the design will be lead free.
Global: Since this design serves mostly as an environment monitoring system, it will be compatible in any location the user intends. This implies it can be used both locally and globally.
Ethical: Our design displays both ethical and professional responsibility since we will not only develop but also implement the design through our personal knowledge and experience.
Health & safety: There are no health and safety concerns over the manufacturing of this product.
Quality / Reliability: The estimated life of the product is about seven years which is sufficient for long-term use as well as the goals intended for the use of the product.
Manufacturability: Our current design utilizes various existing components and processes making it manufacturable by already-existing methods.
Sustainability / Maintainability: The product will be maintained by each respective user and software/firmware upgrades are distributed via the internet making them easily attainable.
Click image for PDF
Click image for PDF
Reference Designators | Description | Digikey Part Number | Price Each | Quantity | Total |
---|---|---|---|---|---|
IC1 | Voltage Regulator | LM1117MPX-5.0/NOPBCT-ND | $1.10 | 1 | $1.10 |
U1 | ATMEGA328 | ATMEGA328-AURCT-ND | $3.51 | 1 | $3.51 |
U2 | Voltage-Level Translator | 296-21929-1-ND | $1.69 | 1 | $1.69 |
ULN1 | ULN2803 Darlington Driver | 296-15777-1-ND | $0.90 | 1 | $0.90 |
Crystal | 16MHz- XTAL-08900 | 490-1198-1-ND | $0.48 | 1 | $0.48 |
S1 | SWITCH TACTILE SPST | CKN9104CT-ND | $0.75 | 1 | $0.75 |
R1 | Resistor 10k 0805 | 311-10KARCT-ND | $0.01 | 1 | $0.01 |
C1, C2, C5, C6, C7 | Capacitor .1uF 0805 | 311-1361-1-ND | $0.01 | 3 | $0.04 |
C3,C4 | 47uf cap | PCE3890CT-ND | $0.55 | 1 | $0.55 |
S1, S2, S3, S4, Vin | Screw Terminals | A98159-ND | $1.04 | 5 | $5.20 |
D1 | SMB Diode | ES2DFSCT-ND | $0.49 | 1 | $0.49 |
D2 | Green 1206 LED | 516-2825-1-ND | $0.37 | 1 | $0.37 |
D3, D4, D5, D6 | Red 1206 LED | 160-1456-1-ND | $0.36 | 4 | $1.44 |
R3, R4, R5, R6 | Resistor 220 | 311-220ARCT-ND | $0.01 | 4 | $0.03 |
PCB | $10.00 | 1 | $10.00 | ||
Total | $26.56 |
Click image for PDF
The Django central management server will run on a standard Apache web, and MySQL database server. This software and its dependent libraries can be installed with the package manager found within many linux distributions.
The beaglebone creates a physical link between the internet and low level hardware like the custom PCB. The device will work with the supplied software once pyserial and the adafruit beaglebone libraries are installed. These can also be installed using the built in package manager.
The system can be managed from any standard web browser, including tablets, phones, and computers. The software should be cross-browser compatible, though WebKit based browsers such as Chrome and Safari are recommended.