August 2008

Department of Electrical & Computer

Engineering’s

The proposed senior design will do just as the title states re-trieve a drink autono-mously and return to the user. The B.R.R. will start at a home base placed approxi-mately ten feet from a drink placed on top of a table. Using a sophisticated infrared beacon and receiver system the robot will search out the table beacon and then track towards it.For long range

tracking two 38 kHz receiver modules will be used. In order to distinguish between beacons each beacon will be pulsing with different carrier frequencies. When the modules receive a signal from either beacon (table or home) the Arduino Microcontroller will check how many pulses per second the beacon is send-ing out and decide to track or find the right beacon. Along the way the robot will also avoid any ob-stacles that may be in its way. The obsta-cle avoidance was implemented using a single parallax sonar ping sensor. Once an obstacle is de-tected the robot will enter an avoidance algorithm and move around it and find the beacon once more.

Once close to the table beacon the second infrared re-ceiver pair will take over control of the robot. Short range infrared detection was implemented using two VTT9003H phototransistors in common emitter con-figuration.The output from

the transistor will be fully rectified into a dc voltage level and fed into the microcon-troller. Once properly aligned and close enough to the drink the super structure

will then retrieve the drink in a plowing fashion. Once retrieval is complete the robot then returns to home base.

Beverage Retrieving RobotTeam BRRMatt Gossage, John Conrad, Mike Parker, Sung Jim Kim

In order to curb the increasing demand for more efficient traffic light timings at intersections, the dynamic traffic light timing system uses much more sophis-ticated algorithms that efficiently move traffic. From its inception, the entire focus of this project was to decrease the frustration currently being faced every-day on the roads around town. There will be less time spent at the wheel cursing at traffic lights that are not appropriately timed, and the amount of gas that could be saved collectively across the board would help the end users wallet. Using nothing more than a webcam connect to a pc, a hardware decoding PIC, and some complex software algo-rithms, this design could be retrofitted to most any, if not all intersections across the United States.From a hardware perspective, a USB to PC interface board was used to take the results from the PC

and transmit them as digital logic to the hardware decoding PIC. Six inputs and twenty outputs were used to decode the signals coming from a USB Interface board. With the PIC programmed to crunch through forty three different traffic light conditions, it would determine the correct one and digitally output the case to the traffic lights. While all of this is taking place, the webcam (that has a bird’s eye view of the intersection) is continually updating the software with flow rates and is determining the most efficient way of timing the traffic signals for the next case.From a software perspective, a few different algorithms used in tandem with one another are imple-

mented to solve the complex issue of traffic light timings. The webcam has four regions that it moni-tors, one for each of the north, south, east and west traffic directions. Each region is right above each direction of traffic before entering the intersection. The webcam software does the frame compari-sons. If something changed between frames 1 through 3, it will count that as a car.The flow rates are monitored and according to how many cars pass through a region being that is being

monitored, an appropriate light timing will be generated and sent to the PIC to output to the traffic lights.The demonstration of this project was done by using an automated hot wheels course that we de-

signed and constructed. This way we could semi-accurately model what would occur in real-life, without hav-ing to physically push cars through the intersection during the demonstration. This was done by using four bumpers which contain a variable voltage DC motor that will propel the matchbox cars forward.In conclusion, this project showed

us all that the engineering skills and practices that we have learned along the past four years of school can have far-reaching applications. As a group, we learned how to improve communi-cation skills, and to work effectively as one, where nobody was left behind. The project was a fun one, and was an experience that will not be easily forgotten!

Team: Tony Faillaci, Ben Hughes, John Gilroy, Justin Porter, & Zach Zientek

Dynamic Traffic Light Timing System

In the evolving field of robotics and artificial intelligence, there is interest in the development of small, cognitive, autonomous vehi-cles. Our project’s goal, based on the research of Dr. Takis Zourntos, was to convert an RC helicopter to fly autonomously while seeking a target and navigating an obstacle course. Robots of this type can be used to gather information in environments where human pres-ence is unfeasible or unattainable. A key feature of our design is that it is modular which makes for sim-pler future development. An innovative aspect of our design

is that it acts as a non-linear control system, with the use of a series of feedback control loops rather than the scripted behavior of a computer. The four main modules are the cognitive core, sensor module, ac-tuation module, and power module. The sensor module consists of ultrasonic sensors, infrared sensors, and a compass that relay information about the surrounding environment to the digital signal processor. The helicopter is programmed to fly in a certain distance in a pre-determined direction which is controlled by the compass sensor. It will use the ultrasonic sensor mounted

Autonomous HelicopterTeam Autonomous Helicopter: Ashley Berger, Kathy Baca, Scott Ekeland, David Winslow

underneath to control its elevation, and the sen-sors in front and on the side to detect obstacles in its path. The SRV Blackfin DSP is the “brain” of the

helicopter in the cognitive core. Using pre-de-termined algorithms, the DSP determines the desired course of action for the helicopter and sends signals to the actuation module. The

actuation module includes the helicopter’s servos and motors that control the rotor and blades. Since the battery supplies 7.4V, it is necessary to have voltage regulators to distribute power to the DSP and other modules. These elements make up the power module. Though not all components of

the original design were imple-mented and working, the final product provides a solid platform for future research. Converting a RC helicopter into a vehicle that lifts-off, hovers, and performs autonomously is a notable ac-complishment, and this platform has made available the potential for numerous applications.

Our goal was to design and construct a com-pletely automated greenhouse that needed very little input from an operator. The solution to this was through the use of analog sensing and con-trol circuitry interacting with a looping program. All of the logic was implemented with the Arduino Diecimila and microcontroller board based on the Atmega168. This board was perfect for the design since it included 6 analog input ports, 14 digital outputs, a USB connection and a 16MHz crystal oscillator. It also made programming very simple since it provided libraries and an en-vironment for programming the mi-crocontroller in a cbased language. This Arduino board became the central hub of the design, constantly monitoring details such as relative humidity and temperature inside the greenhouse as well as initiating the controls to maintain a steady envi-ronment.To make it easy on the operator,

a simple graphical interface was programmed to allow them to re-program certain parameters without having to access the code. The parameters that were monitored by the microcontroller were minimum and maximum relative humidity and temperature, duration of exposure to light, and an irrigation system.

Automated GreenhouseTeam Automated Greenhouse :Nathan Phetteplace, Carlos Garcia, Michael Thomas, Stephen McLauchlin

Since the Arduino board had a USB connection, it was simple to connect to a computer with the GUI and com-municate between them. The Arduino provided a serial emulator, so com-munication was similar to sending and receiving data over a serial port. To constantly monitor the humidity and temperature levels, the microcontroller sent data every second while the GUI constantly polled the serial port for up-dates. The GUI was programmed with algorithms to convert the data from a 10 bit number representing voltage into the actual values that we read. As the data was constantly monitored by the microcontroller, a separate circuit was used with NMOS transistors and 12 volt sources to control fans and ac-

tuators for changing the greenhouse environment. The gate of each NMOS was supplied by a high or low voltage from the Arduino’s digital outputs.Since the microcontroller was programmed to

constantly monitor the system, the algorithms on system were able to make a decision about which outputs to write high and low in order to maintain a steady environment. From there, all the operator must do is submit their desired parameters.

The purpose of the project is to build a self-powering, obstacle-avoiding, energy-effi-cient, and user-friendly autonomous lawn mow-er. We have integrated two obstacle avoiding systems, sonar and bumpers, which work together to guide the mower around differ-ent obstacles in its path. The sonar system detects objects in front of the robot and takes evasive action to avoid collision. The bumper system serves as a back up to the sonar. In case of sonar malfunc-tion, upon collision with an object, the bumpers will signal to the microprocessor that an obstacle has been encountered and action must be taken accordingly. The artificial brain of the Lazy Mower is Microchip’s 18F2331 PIC microcontroller. The microcontroller processes the acquired informa-tion from the sonar system, the motor encoders, and the bumper system and commands the servo motors to act as needed. We chose to use servo motors, because they are con-trolled using pulse width modu-lation, which provides precise turning and speed adjustment capabilities. We use servo en-coders to determine the exact position of the Lazy Mower. This enables us to make turns at pre-cise angles in order to navigate around obstacles accurately. En-ergy efficiency is achieved using a grass sensing circuit. An LED-photoresistor pair determines the height of the grass and engages the mower’s blade only if the grass level is tall enough to be cut as specified by the user. For our prototype, we use a

simple computer fan to simulate the mower’s cutting blade. The mower’s power system consists of two independent AA battery

Lazy MowerTeam Lazy Mower: Andrew Menard, Brittany Hedrick, Conrad Pramono , Derek Aquiningoc, Emil Mihov

packs. We use one bat-tery pack to solely pow-er the servo motors, which are the source of greatest power con-sumption. The second battery pack powers all other systems. During the course of the proj-ect, we combined the engineering expertise of our team members to design multiple elec-trical circuits required to power and operate the mower’s systems. Furthermore, we com-bined our electrical knowledge and com-

puter programming abilities to generate the logic that governs the PIC microcontroller. In addition, we constructed our own robot chassis by modi-fying a preexisting aluminum frame and using multiple Plexiglas mounting decks. The project was mechanically challenging because its fabri-cation was very intensive since we did all body work ourselves, implementing Plexiglas as our main construction component, modifying it for all intents and purposes.

Concept: The concept we undertook was to create a comput-

er controlled whiteboard which would convert several inputs into a physical representation on a dry-erase board. Inputs include: freehand user interface via a mouse, temperature sensor, and PHP interaction with an internet source (in this case, weather).The output would consist of motor controlled verti-

cal and horizontal axes as well as an actuated pen to lift or press the tip to the board. This system is easily adaptable to existing writing boards, uses low-cost materials, and can be useful in many ap-plications such as a teaching environment.Realization:To drive the axes, we employed a lead screw and

load drive which uses a stationary nut on a long threaded rod to support the load. Two stepper mo-tors spin the entire threaded rod, forcing the load linearly along the rod. The rods are supported by oiled bearings to allow them to turn easily.The whiteboard is mounted into a heavy wooden

frame with metal plate brackets on the corners and vertical wooden struts in back. The horizon-tal axis is fixed directly to the frame with the lead screw and roller track both along the top. The track supports the weight of the vertical axis, while the threaded rod drives it left and right. A smaller wooden frame contains the vertical lead screw and writing platform. Two custom metal tracks span the length of the vertical axis to guide the wooden writing platform on which the pen actuator is mounted. Several custom fitted brackets and con-nectors were made out of Shapelock, which can

Automated WhiteboardTeam Automated Whiteboard: Bobby Childress, Ross Dusenbury, Jung Kim, Charles McTygue

be heated and molded into a hard plastic of most any shape, and various screw plates.Control:To control the motors and actuator, we used flash to

convert vectors into scaled commands correspond-ing to either the U/D or R/L motor to move left/right/up/down the number of turns corresponding to the length of each vector. Text was also converted into a string of characters and then referred to a custom li-brary which contains scalable commands for creating each character A-Z, 0-9. The motor commands are sent to the Arduino board which converts them into high/low signals to be sent to each respective motor control circuit. The movement motors are wired in bi-polar mode and controlled by a double h-bridge circuit to allow a four-bit input to control forward/re-verse movement. The pen actuator is controlled by an H-Bridge circuit controlled by a two-bit input from the Arduino for the up/down actuation for the pen actuator. The flash commands are easily converted

into length and direction commands for the stepper motors as well as up and down movements for the pen to write. A reset function also enables the pen to return to the upper left position to maintain relativity to the user interface.Result: We were able to successfully cre-

ate a writing machine which depicted the gathered information from all three sources. The problems encountered kept us from adding multiple marker colors and an eraser. Also, the drawing function is very slow, but could be improved by using differ-ent motors or wider threaded lead-screws. Over all, our goal was completed and the automated whiteboard functions as an in-formation display and freehand writing tool.

As the number of cars in the streets increase greatly due to various reasons, the inconvenienc-es associated with them also increase at a rapid rate. One of the most omnipresent among these problems is associated with parking lots. The frustration associated with finding a vacant space in a parking lot has become synonymous with modern day existence. Due to these reasons, as well as numerous personal experiences, we decided to design and implement a parking lot management system. This system would manage the traffic going into a parking lot by notifying the drivers about the avail-able slots for parking. If this information is known at the entrance of the parking lot, then a considerable amount of time can be saved that would otherwise be spent in going aisle by aisle trying to

Parking Lot Management SystemTeam Parking Simplifiers: Muneer Naqvi, Raheel Zubairy, Ayush Tambi, Raheel Khoja

find an available slotThe goal of our project is for an LED map to dis-

play available parking spots for a demo parking lot of sixteen parking spots. This was accomplished by having a sensor at each parking spot, which checks if there is a car parked at that spot or not. There is a matching LED for each spot, which will be on if the corresponding spot is occupied. In addition to this, there is a push button next to each LED through which the user can reserve the spot till he/she gets to that spot. This demo parking lot constructed is similar to an actual parking lot so could be used for industrial purposes. Also, one of the parking spot display uses a wireless trans-mitter and receiver through which the output LED receives data from the sensor and push button wirelessly. For industrial purposes, this would be useful if the data from the sensor is communicated wirelessly to the interface as it would decrease considerable amount of wiring. This project uses an Infra Red sensor which send

a ‘high’ signal if it detects and object within its range. This signal was connected to a PIC micro-controller which controlled the output LED display for four parking spots. The PIC received inputs from four sensors and four push-buttons and had four output LEDs connected to it. The four PICs control the functionality of the fifteen parking spots with one parking spot display working wirelessly.

The Mixmaster II is a computer controlled automated bartending device. The primary development goal is to provide a colorful and intuitive touch screen based user interface that guides the consum-er through the process of prepar-ing an iced beverage of several different fluid ingredients. The reason for undertaking the project is simple: humanity is inherently lazy. Engineers by nature seek to develop devices that make life easier. What could possibly be easier and more satisfying than touching colorful icons to create fluidic nirvana?

Background Information: To realize the Mixmaster II, several technologies

and disciplines must synergize. First, a small form factor computer serves the role as a control-ler for dispensing ice, pouring the correct quanti-ties of fluid ingredients, and mixing the resulting beverage. This computer also provides the touch screen based user interface, and maintain a da-tabase of “tasty” beverages. A USB GPIO board controls a series of 12 pinch valves in a gravity

Mixmaster II Team Mixmaster II :Jonathan Sudduth, Charles Krebs, Heath Misley, Thomas Wilson

fed fluid dispensing system, and the motors that automate the dispensing process. The dispensing process starts by the user

selecting a drink via the touch screen interface. At this point, the user can dispense ice into the glass at the touch of a button, filling approxi-mately 1/3 of the glass with ice per touch. Once the mixing process is started via the “Start Mix-ing” button, the stirring rod is lowered into the glass and the Mixmaster dispenses the required fluids simultaneously. Both the viscosity of the

fluid and the 1/8” in-ner diameter of the latex surgical tubing lines govern each fluid’s flow rate. The surgical tubing en-sures that the fluids remain sanitary and guides each fluid to a common output mani-fold. A pinch valve starts and stops flow inline. While dispensing

the fluids, the stirring rod mixes the drink, and ascends back into the machine once pouring is finished. The resulting bever-age is now ready for consumption.

Demonstration Day Winners

First Place tie-Team Mixmaster IIJonathan Sudduth, Charles Krebs, Heath Misley, Thomas Wilson

First Place tie-Team Automated WhiteboardBobby Childress, Ross Dusenbury, Jung Kim, Charles McTygue