Instructor:
M. A. Osman
School of EECS
Richland, WA 99354
Table of Contents
Executive Summary 3
Introduction 3
Project Description 4
Target Technical Specifications 5
Setbacks 6
New Scope and Direction 7
Project Management 9
Modeling, Simulation, and Engineering Analysis 11
Conclusion 16
Recommendations and Future Work 16
References 17
Executive Summary
This report focuses on the activities that Team Rainier has made between January 11 and April 23, 2010. The team was originally updating the palletizing process for J. Lieb Foods. Currently J. Lieb Foods has a rotary operated control system that controls the Programmable Logic Controller (PLC) which in-turn operates the palletizer. Team Rainier was updating the control system to a touch screen control for the operators and an upgraded PLC to control the palletizer.
Through the process of economic analysis J. Lieb had selected the PanelMate 1000 as their touch screen and the quantum as the PLC. Due to recent developments with J. Lieb the project stalled and now has a different scope and direction.
Team Rainier has been in contact with Dr. Allan Felsot of the Viticulture and Enology Program at Washington State University Tri-Cities. Dr. Felsot is the director of the green house at the university campus. Currently he is in need of controllers for the lighting system.
The grow lights in the greenhouse are strictly on or off and are currently all controlled by simple on/off switches. With the installation of a PLC the lights will be programmable as to when they turn on and off, eliminating the need for someone to continually be present to physically turn the lights on and off.
Installation of an automated system will also enable Dr. Felsot to expand the processes that are automated and to make upgrades and changes as needed.
Team Rainier selected the Pico Series PLC and ordered the hardware for the control system. The process of programming and testing the PLC is complete, after which installation of the hardware will be executed.
Introduction
Team Rainier spent the months of January and February attempting to acquire the necessary hardware and software to complete an upgrade of the palletizing process for J. Lieb Foods. J. Lieb Foods is a specialty food company that focuses on organic and niche markets. The process began with J. Lieb Foods expressing a need to update their palletizing process. Their current process includes a rotary control system and PLC. PLC’s have been in food processing plants for about twenty years. Before that only Distributed Control Systems (DCS) were used. They are used in all food processing plants because of the cost effectiveness, reliability, and ease of use. PLC’s are cost effective because they are simple to make, roughly five hundred dollars at the top, end and have minimal recurring cost. They use ladder logic as the programming platform, which is understood by many people, not just highly skilled programmers.
No major milestones were achieved as team Rainier was met with setbacks due to outdated software and economic concerns. J. Lieb Food’s palletizing process was significantly out of date. They were attempting to upgrade to newer, but not new, hardware and software.
The new project is to provide an automated control system for the lighting in the greenhouse at WSU Tri-Cities. This will allow the staff to control lighting and maintain the levels needed for the students and faculty to conduct their projects in a more efficient manner. [1]
The new project began in earnest March 1, 2010 with a walkthrough of the greenhouse and meeting with Dr. Felsot to determine if there was a process that team Rainier could automate to make the operation of the greenhouse more effective and efficient. [2] Dr. Felsot requested that the lighting be automated.
Figure 1: Recent photograph of team Rainier at the green house at WSU Tri-Cities Campus.
A major milestone was reached in late March when the Pico Series PLC was selected, ordered, and arrived. The next major milestone to be completed was the programming for the PLC which was finished at the end of April.
Project Description
Team Rainier’s goal was to update the palletizing process at J. Lieb Foods in Kennwick, Washington. Their process was seriously out of date and was in need of an upgrade. Currently, J. Lieb has a rotary control system that controls a PLC which in turn controls the automatic palletizer. The rotary-control-system-PLC combination is used to instruct the palletizer which pattern cases should be put in and how high pallets should be stacked.
[pic]
Figure 2: Layout options for the palletizer
Two people were to be responsible for programming the newly selected Quantum PLC that would allow J. Lieb Foods to meet the goals listed below in Table 1.
Target Technical Specifications
|No. | |Need |
|1 |The PLC |stacks pallets in 16 different patterns. |
|2 |The PLC |stacks pallets to 10 different heights. |
|3 |The PLC |Interfaces with HMI to provide control via GUI on touchscreen. |
Table 1: Target Specifications
The Quantum can direct the palletizer to arrange the boxes/cases from a selection of 16 different patterns of placement and 10 choices for height. It, also, allows for easy upgrades and changes to be made to this process. Below, in Figure 3, is the configuration of the Quantum.
[pic]
Figure 3: Quantum wiring configuration.
Two other people were to be responsible for writing the code for the touch screen. The original choice was a Quickpanel touch screen but J. Lieb opted for the PanelMate 1000, shown below in Figure 4. The PanelMate 1000 communicates with the Quantum and the Quantum has the capability to communicate with the current palletizer that J. Lieb is using.
Setbacks
Originally J. Lieb had selected the Quickpanel brand of touch screen to be used but quickly changed course due to the economics of the software requirements for the Quickpanel. The selection of the PanelMate 1000 was effective economically but created a whole host of problems. The software runs on either Windows 95 or 98. Obtaining a computer that would run windows 98 became a problem. The team tried several options including virtual PC and having local computer service organizations attempt to install 98 as a dual boot. As it turned out all of the computers the team had access to were too new to install Windows 98.
Obtaining the software became a cumbersome process as well. Several attempts were made to communicate with John Schmidt by Robin Mitchell the team liaison. Eventually Mr. Schmidt referred us to the Eaton Electrical website to obtain the software. The software was free but had to be downloaded to floppy disks.
[pic]
Figure 4: Photograph of PanelMate1000 from EatonElectical.com
Communication, software, and hardware issues severely hindered the process. John Schmidt of J. Lieb Foods stopped communicating with the team as the economics of the project were in question. Eventually, J. Lieb made it known that they would not be purchasing the PLC which put the project in jeopardy. Team Rainier attempted to procure a PLC through alternate means that could be used for the project. The only possibility of obtaining a PLC was on a loan-basis with which the team could simulate the process but would not be able to implement. Finally, after several avenues were exhausted, the project stalled.
New Scope and Direction
An alternate plan for the project was developed during the week of March 5, 2010. After a progress meeting February 26, 2010 it was suggested that the team contact the director of the green house at WSU Tri-Cities (shown below in Figure 5) and inquire if there are any processes that can be automated.
[pic]
Figure 5: Plants being grown for student projects in the WSU Tri-Cities Green House.
[pic]
Figure 6: PAR Source lighting system
Dr. Felsot is the director of the green house and a professor in the Viticulture and Enology program. He has several processes that can be automated. At this time Dr. Felsot would like Team Rainier to concentrate on automating the control process for the lights in the green house.
Currently there are 11 grow benches, each having their own lighting system pictured above in Figure 6. The PAR Source 120V 9.8A grow light is to be used in conjunction with RD, SG, PRO, GL, GLX Series luminaries.
At this time the light source for each bench is controlled by its own on/off switches as part of the Wadsworth Control System. It is the EnviroStep NE MA-1 which is a 115V AC system pictured in Figure 7 on the next page.
Automating the lighting system will enable Dr. Felsot to maintain lighting conditions in the greenhouse in a more consistent manner. This will allow him to more accurately manipulate the growing process [3].
Project Management
Team Rainer’s original project was not able to be completed due to resource issues. A contingency plan was to switch projects and use WSU as our client; our scope is now well defined with the direction that has been given. This plan had to be put into action due to the lack of J. Lieb’s resource availability. Substantial progress has been made towards completion of this project now that Team Rainier has been able to actually move forward on a project. However, as the previous project halted due to financial resources, the new project’s biggest complication is limited time resources. With the possibility of not having enough time to complete all aspects of this new project due to the compressed schedule, the Team is concerned that they will not get to install and configure all of the hardware components. Each member from Team Rainer, for the most part, has been individually working on their own assigned task(s). The main reasons, at this point, for group meetings are to transfer data/products to other team members and complete the reports and final paper. A meeting is scheduled the week of April 26, 2010 with our mentor/client to demonstrate and obtain approval/acceptance of the test bed platform. The team was allowed full access to the project location (greenhouse) for the duration of the project which was a great resource, providing them the ability to interact with the existing hardware.
As stated above, Team Rainier’s biggest obstacle was the loss of our sponsor/client J. Lieb foods due to their budget and resource availability. Further issues arose after this; finding an alternate project with sufficient scope that could be completed within the timeframe allotted and then procuring the necessary hardware and fabricating the test bed within this timeframe and financial allowance provided. It has been difficult to find superior products that will meet all the needs of Team Rainier’s client.
[pic]
Figure 7: Dr. Felsot and Stuart Danby pictured in front of Wadsworth system showing the 12 on off switches.
Below, in Figure 8, is the updated schedule, incorporated into the new project as if the project was awarded at the beginning of the semester. Located on this schedule there are five key milestones. It should be obvious from the chart that the team’s two most time consuming portions of the project will be the programming which takes over half the time. Testing of the software from our LED board that was fabricated is one of the most important things taking up a substantial amount of time. Rainer’s schedule in reference to completion of schools allows for a little slip time at the tail end of the project. Team Rainer has supplied the necessary drawings for installation along user manuals, programming guides, specification sheets for all hardware used in this project.
[pic]
Figure 8: Gantt Chart
Modeling, Simulation, and Engineering Analysis
Three factors will help determine which controllers for automation of lighting in the greenhouse. First, we will need to find a controller which provides enough I/O to complete the project. In this instance we will need at least 11 inputs and 11 outputs as there are 11 bays that we will need to control lighting for. As most controllers have an even number of I/O, and usually in multiples of four, we will most likely obtain a controller that can handle a minimum of 12 inputs and outputs. Below, in Figure 9, a wiring diagram is depicted for a 12-output Pico PLC by Allen Bradley. More inputs can be used if we intend to use light sensors to help determine grow light condition statements and states in each bay.
Budget will be our second decision-making factor. The short-term nature of our new project has forced us to purchase equipment quickly. All funds are coming from the WSU Tri-Cities and are very limited. Finally, we will want to provide the possibility for future expansions to this project. There are other atmospheric conditions that could be measured and automated. Our project will deal directly with the lighting but the ability to provide the infrastructure for further automations would be ideal. However, current funding and time constraints will both play bigger roles than this factor when deciding on the PLC.
[pic]
Figure 9: Wiring diagram
Ultimately we purchased an Allen-Bradley Pico series PCL model 1760-L18BWB-EX, and expansion module 1760-IA12X0W6I. This combination provides us with 12 available relay outputs; 12, 24v DC inputs; and 12, 120v AC inputs. This will allow for the simple configuration of using existing mechanical light switches to bypass PLC timing program to engage the grow lights manually. This will also leave 12 DC inputs for further expansion and options. There are several other advantages to this hardware as well. The PicoSoft software for programming ladder logic on this series of devices is available free of charge and is complete with simulation and testing capabilities. Another convenient feature is the integrated user command and control, and programming interface. This consists of a small LCD screen for output, as well as a quad directional control rocker and four context sensitive buttons for user input. This allows for program feedback directly on the device. It also allows for the entire ladder logic to be viewed and edited without any software or computer. This is very convenient if changes need to be made on the fly or short notice. Figure 10 on the next page depicts the Allen-Bradley Pico controller with the attached I/O expansion module.
[pic]
Figure 10: Allen-Bradley Pico controller with attached I/O expansion module
Our simulation phase consists of using the built in features of PicoSoft 6. PicoSoft can simulate hardware and the ladder logic programming. It allows virtual inputs to be turned on and off, while observing the result of both the ladder logic and device outputs. Changes and edits in code can be tested immediately without uploading the program to the device. Figure 11, on the next page, illustrates the Graphical User Interface (GUI)of the software. In simulation mode the “wires” will turn red following the path of activated logic. This is useful for debugging purposes. If an unexpected result occurs, the path taken can be easily traced back to the point of the error in logic.
[pic]
Figure 11: Screenshot of PicoSoft 6 software
Our prototype phase consists of a full test of the Pico controllers using LEDs in place of the greenhouse lighting. A perforated board was used to solder a set of LEDs, each in series with a resistor. In this simple configuration the diode has a 2.7 volt forward bias and the 820 ohm resistor limits the current through the diode to approximately 26 milliamps. This is necessary to prevent the diode from being ruined by a high level of current flow. Figure 12, on the next page, shows the arrangement of LEDs and resistors.
The relay outputs of the PLC were then supplied with a 24 volt DC power source. Then the activation the program and allowed the PLC to run just as it would if installed in greenhouse. The only major difference would be the use of the 24 volt inputs as opposed to the 120 volt AC inputs for the manual activation functionality. When activated the LEDs will come on in place of the grow lights and supplying 24 volts to an input will cause the corresponding LED to stay on regardless of instruction from the ladder logic. Figure 13, also on the next page, depicts a working prototype setup as seen from illuminated LED. It highlights the LCD screen and user interface, as well as our LED simulation board.
The final installation design is much like the prototype. The PLC will be mounted and powered by a 24 volt power supply. The existing light switches used to control the grow lights can be left in place. They will then be rewired to the 120 volt inputs of the Pico controller. This will allow a user to turn on a light in the same manner currently used, by simply flipping a switch. The built in LCD screen and buttons will be used to make changes to the grow light schedules. The real time clock timers in the ladder logic can be directly manipulated through this interface.
[pic]
Figure 12: LED demonstration board
[pic]
Figure 13: Working demonstration prototype
Conclusions
In conclusion team Rainer has overcame multiple obstacles throughout this semester to complete an automated control system project. The team has done all the necessary research, programming, drawings and testing needed to install the Pico controller system in the Greenhouse for the purpose of automating the grow light system. Through the prototype and final design the team has met the objectives required by the client and this project. The test bed LED board demonstrates how the lights in the greenhouse would act while functioning in conjunction with the Pico controller.
The Teams success on this project is accredited to the determination of the individuals on the team to complete the project. Also, the ability to overcome road blocks due to the diversity and flexibility within each individual to complete the assigned tasks. It wasn’t until the integration and implementation of the test bed that it was essential that Team Rainer was able to communicate efficiently and effortlessly with each other.
The project was completed and met all objects determined: Supply the greenhouse with an automated control system for the lights in the greenhouse, all documentation (coding, technical specifications, installation manuals and drawings) and hardware. Team Rainer Out.
Recommendations and Future Work
If Team Rainier had another year to work on the project we would install a wireless sensor network that could take luminosity readings in the greenhouse and adjust the lighting inside the greenhouse accordingly. [4] We would also provide remote access to the system so that adjustments could be made manually from a remote location. [5,6]
References
[1] J. Markvart , E. Rosenquist, H. Sorensen, C. Ottosen and J. Aaslyng “Canopy Photosynthesis and Time-of-day Application of Supplemental Light,” HortScience 5 Aug. p. 1284-1290, 2009
[2] H. Liu, Z. Meng and S. Cui “ A Wireless Sensor Network Prototype for Environmental Monitoring in Greenhouses” Wireless communications, Networking and Mobile Computing, 2007. DOI: Beijing CHN 10.1109/WICOM.2007.584 ; 08 October 2007
[3] I. Seginer, L. D. Albright, I. Loslovich, Biosystems “Improved Strategy for a Constant Daily Light Integral in Greenhouses,” Engineering Jan2006, Vol. 93 Issue 1, p69-80
[4] T. Ahonen, R. Virrankoski and M. Elmusrati “Greenhouse Monitoring with Wireless Sensor Network” University of Vaasa Department of Computer Science Telecommunications Engineering Group DOI: 10.1109/MESA.2008.4735744.
[5] M. Demirbas, K.Y. Chow and C.S. Wan “Insight: Internet-Sensor Integration for Habitat Monitoring” World of Wireless, Mobile and Multimedia Networks, 2006, Buffalo-Niagara NY
[6] S. Janos, G. Martinovic “Web-Based Distant Monitoring and Control for Greenhouse Systems Using the Sun SPOT Modules” Intelligent Systems and Informatics, 2009. SISY ’09. 7th International Symposium. Subotica, Serbia DOI: 10.1109/SISY.2009.5291170.
