Grain Moisture Detector for Industrial Applications

Transcription

1 University of Manitoba Department of Electrical & Computer Engineering ECE 4600 Group Design Project Project Proposal Grain Moisture Detector for Industrial Applications by Group 07 Dimitri Anistratov Shucheng Gu Edinam Tettevi Robert Brandt Kathy Nguyen Academic Supervisor Joe Lovetri Industry Supervisors Ian Jeffrey Academic Supervisor Paul Card 151 Research Inc Colin Gilmore 151 Research Inc Date of Submission September 26, 2014 Copyright 2014 Dimitri Anistratov, Robert Brandt, Shucheng Gu, Kathy Nguyen, Edinam Tettevi,

2 1 Introduction As the world population increases, there is a growing need for resources, particularly food. In , twelve percent of the worlds population of over 7 billion people was malnourished. That means 842 million people suffered from chronic hunger in the past few years [1]. Studies show that reversing hunger involves more than increasing production. In fact the amount of grain produced by the global farming community is enough to feed the earths human population and sustain life. However, in order for this to be possible, the grain produced needs to be stored in a suitable location that facilitates preservation. For this to be done effectively, stored grains will have to be monitored to detect the onset of external agents that accelerate grain spoilage. Currently, grain bins are monitored with temperature sensors to help predict moisture levels of the grains; however this does not accurately depict the moisture levels in the bins or the location of the contamination due to insect activity inside the silos or temperature fluctuations by weather conditions outside the silos. Our project is aimed at ensuring the early detection of these agents that accelerate grain spoilage through electromagnetic imaging techniques. Using a VNA, we can analyze the s-parameters of the bins contents and produce an image that displays the grains dielectric permittivity properties to detect water contamination. However, VNA devices come in very high prices, so the projects focus is to design a more affordable and portable system for real practice. This microwave imaging system will consist of a signal processing software-code integration between antenna arrays, a portable vector network analyzer and an RF multiplexer, with the final product providing accurate, affordable and accessible information to farmers in time for them to take necessary control measures to protect the unaffected grain stock. The project will be broken in three phases: research, design and field-testing over the course of the next seven months. At the end of which our antenna design should give accurate readings from a grain bin through an RF multiplexer to a VNA which would allow a computer software to generate an image of the stored grain and its current state.

3 2 Project Details 2 Project Details The project will consist of the integration of several different hardware components as well as software for handling the transmission of data between these hardware components. Alternate antenna designs will also be looked at. The hardware components that will need to be integrated in the project include; an array of antennas, a vector network analyzer (VNA), an RF multiplexer and a microcontroller. Two software components will be required; one for communicating with the VNA and processing the received data into a usable format and one for taking this formatted data and creating an image of the grain bin contents. 2.1 Antenna Array An array of 16 antennas will be built and installed in the full size grain bin. One antenna will be used to transmit a signal while the other antennas will receive this signal. After each antenna has acted as the transmitter, a 16 by 16 data matrix will be gathered. The design of the antennas is an important consideration as there could be considerable pressure on the antennas due to the contents of the grain bin. The antennas need to be kept low profile to ensure that minimal pressure is exerted on them so that damage to the antennas or the grain bin itself is avoided while still providing the performance required to obtain useful data. In order to help in the design of these antennas, two smaller models will be used which can be tested in the lab with existing hardware. 2.2 Vector Network Analyzer A 2-port vector network analyzer will be used to transmit a signal and receive the signal reflected back. The VNA together with the antenna array and RF multiplexer (discussed below) connecting them will capable of generating the data required to produce an image of the grain bin contents. Lab quality vector network analyzers are very expensive, usually costing tens of thousands of dollars. Since the frequencies being transmitted and received from the antennas are relatively low, - 2 -

4 2 Project Details the vector network analyzer can be much more affordable and portable than those usually found in a lab. 2.3 RF Multiplexer An RF multiplexer will be used to integrate the array of 16 antennas with the 2-port VNA. The multiplexer will determine which antenna is acting as the transmitter and which ones are acting as the receivers as it cycles through the array. 2.4 Microcontroller A microcontroller will be used to communicate with the VNA and RF multiplexer and collect the generated data. Software will be loaded onto the microcontroller which will allow it to send instructions to the VNA and receive data back. The microcontroller will also format the received data such that it can be processed later to create an image of the grain bin contents. 2.5 Software Software is required to handle all of the communication between the hardware components and collect the generated data. Software has been written that can accomplish this on equipment in the lab. This software will need to be modified to run on the microcontroller and communicate with the specific hardware components used in the project. In addition to the communication and data collection, software will be used to process the collected data and create the final image displaying the contents of the brain bin and whether or not it contains any moisture. This software will be installed and run on an external PC

5 3 Specifications 3 Specifications The specifications of this project are shown in table 1. The antennas need to have a low profile design and should not interfere with the grains when the bin is being filled or emptied. The RF multiplexer will be designed to have low noise and can handle electric static discharge. The data acquisition system should be able to read 24x24 data points and the VNA device should have an open source interface so it can beimplemented with software that is more designed for the projects specifications and data calibration algorithms. Table 1: Specifications Antenna Freq Range 70 MHz - 90 MHz Quantity 16 VNA Freq Range 70 MHz - 90 MHz Dynamic Range 90 db transmission and 50 db reflection [2] System Type 2-port with S11 and S21 Output Power 0 dbm Z (impedance) 50 Ω RF Multiplexer Array Size 2 x

6 4 Division of Labour 4 Division of Labour The following tables 2 & 3 depict the assigned tasks and milestones to individual team members and also illustrate the division of labour between the team members; each team member is assigned to a specific main task and an additional part of another team members task. There are 3 phases to the project: 1. Research and developement 2. Prototyping and design implementation 3. Final system testing Table 2: Division of Labour Robert Brandt Edinam Tettevi Kathy Nguyen Dimitri Anistraov Shucheng Gu General hardware design and implementation, assist with software development Hardware integration testing, compatibility of parts and interconnection of all components Microcontroller software design and implementation, data acquisition and processing Antenna testing, design and implementation, assist with hardware design Antenna design and testing, alternative antenna design - 5 -

7 4 Division of Labour Table 3: Milestones, Tasks and Division of Labour Milestone Member Name Starting Date Expected Date of Completion Phase 1: Research and Development Research and order a budget vector network analyzer (VNA) that could be interfaced with a microcontroller Assemble VNA (if required) and test Design 3-5 small scale antennas for small scale grain bin to be tested in the lab Integrate VNA with switch box and antennas and produce a working prototype Test prototype system in the lab for a small scale proof of concept Robert, Dimitri Edinam, Robert, Kathy, Edinam Sept Oct Sept Oct Dimitri, Shucheng Sept Nov Robert, Dimitri, Shucheng Robert, Dimitri, Shucheng Phase 2: Prototyping and implementation Edinam, Kathy, Edinam, Kathy, Oct Nov Nov Dec VNA data aquisition Kathy, Edinam Nov Dec VNA and microcontroller interfacing Design of multiplexer Kathy, Robert Nov Jan Robert, Dimitri, Edinan Nov Jan Purchase power supply Edinam, Shucheng Nov Jan Test new components (multiplexer, antennas) with existing prototype Integrate GSM module for wireless internet connectivity Edinam, Shucheng, Robert, Dimitri Kathy, Robert, Edinam Jan Feb Jan Feb Data calibration Kathy Jan Feb Phase 3: Final Testing Field test and calibrate final system Dimitri, Robert, Shucheng Kathy, Edinam, Feb Mar

8 5 Gantt Chart 5 Gantt Chart The GANTT chart in figure 1 indicates the time required to complete all of the tasks involved in the project. Task Days to September October November December January February March April complete Research and development Research and order a VNA Assembly of VNA and testing Design of antennas Integration of VNA, RF switch and antenna Test small scale proof of concept Implementation VNA data acquisition VNA and microcontroller interfacing 15 1 Design of switch box Purchase power supply Test new components 1 1 Integrate GSM module for wireless internet connectivity 15 5 Data calibration Final testing Field test and calibrate final system Fig. 1: GANTT Chart - 7 -

9 6 Budget 6 Budget The proposed budget for this project is shown in table 4. Some component costs are estimated and may be priced less than the estimated cost. Taxes are applied to all parts and shipping costs are accounted for in the cost estimate of the component if supplier is not listed. Some parts may also be available through the Electromagnetic Imaging Lab (EIL) (ie. minivna Pro, etc.) and ordering for them will not be necessary which will further reduce costs. A $500 budget is allocated for the project group which is provided by the department of Electrical and Computer (ECE), while additional funding will be provided by the EIL

10 6 Budget Table 4: Budget SYSTEM MODULE Antenna Array Vector Network Analyzer (VNA) RF Multiplexer Controller MISC. COMPONENT Supplier Part No. Price/Unit Quantity Sponsor Estimated Cost Antenna PCBs Metallic rods ECE $ Portable VNA device 1 EIL $ Coaxial cables & connectors Mouser U500 $75.93/500ft 1 EIL $75.93 MUX/DEMUX Digikey ND $ EIL $2.56 SMA board edge Digikey J502-ND $ EIL $ SMA board edge Digikey ND $ EIL $30.30 SMA-SMA cable Digikey ND $ EIL $56.42 cap 10nF 0805 Digikey ND $ EIL $16.79 cap 100nF 0805 Digikey ND $ EIL $16.06 SPDT Digikey HMC194MS8 $ EIL $78.24 SP3T Digikey HMC245QS16 $ EIL $8.26 SP8T Digikey HMC253QS24 $ EIL $61.68 Raspberry Pi B+ 8GB microsd card Huawei E173 unlocked USB GSM modem Newark 68X0156 $ ECE $43.60 Amazon. ca B KQ $ ECE $27.69 Power Supply ECE $ Electrical components (wiring, EIL $ resistors, capacitors, etc.) Machine Time U of M 8 hrs. $0.00 ECE EIL Subtotal $ $ % taxes $61.27 $ Shipping $43.66 Total $ $ Project Subtotal $ % taxes $ Shipping $43.66 Grand Total $

11 7 Conclusions 7 Conclusions The proposed project is the design of an affordable and portable system that applies electromagnetic imaging techniques to the detection of agents that accelerate grain spoilage. Using a VNA, analysis of the s-parameters of the bins contents will produce an image that displays the grains dielectric permittivity properties to detect water contamination. The proposed budget for this project is $ which will be funded by both the ECE department and Electromagnetic Imaging Lab

12 REFERENCES References [1] FAO, The state of food insecurity in the world, Food and Agriculture Organization of the United Nations. FAO, IFAD and WFP, [2] mrs mini Radio Solutions. minivna PRO [Online]. Available: