Group 2: Parking Garage Monitoring System (PGMS)

From left to right :

Matt Downes

Stephen Osborn

Pawanjit S. Chawla

Anup R. Daniel

• Noticed inefficiency in finding parking spaces in large facilities

• Lack of information regarding parking spot vacancies

• Thought of a solution to this problem by allowing people to check vacant parking spots via the web

• Detection of vehicle occupancy by implementing a parking monitoring system

• Ultrasonic sensors detect presence of vehicles

• Atmel and multiplexers used to group thirty-two sensors to one transmission point

• RF transmitters and receivers used to send/receive data

• Rabbit 3010 module used to process the information from multiple RF receivers.

• Web server used to display vehicle occupancy information

• A web enabled wireless device allows a person to find the closest parking space

• Project consists of 4 modules– Sensor Module– Transmitter Module– Receiver Module– Base Station Module

• Sensor Module– Consists of ultrasonic

sensor SRF04– Used to detect the

presence of vehicles– Connection via RJ-45

jack• Power, ground and ping

are received• Echo is returned

• Transmitter Module, comprised of :– Atmel ATmega8515L

• Controls the mux/demux for the ping/echo• Stores echo information to determine when to

transmit• When transmission is needed, outputs information

via the USART

– Linx TXM-433-LC RF Transmitter• Receives data from the USART• Transmits to receiver module

• Transmitter Module– Connected via RJ-45

to sensor module

• Receiver Module– Consists of Linx RXM-

433-LC RF Receiver• Constantly receiving

data• Connects via RJ-45

module to the base station module

Sends data and ground to the base station module

• Base station module– Consists of rabbit

RCM 3010• Receives data from

receiver module via RJ-45

• Determines if valid data has been received

– Displays the valid data on the web page

– If invalid data is received, the rabbit ignores it

• Web server– Displays parking information

• Outputs the total spots in the garage• Outputs the used spots in the garage

M UX

DEMUX

ATMELATmega8515L

Receivern

Receiver…

Receiver2

Linx RXM-433-LCRF Receiver1

PING

ECHO

SELECT LINE

SELECT LINE

RABBITRCM 3010

Linx TXM-433-LC RF Transmitter

WEB SERVER

TRANSMISSION CELLSRF04UltrasonicSensors

• Constraint Analysis & Component Selection

• Patent Liability

• Reliability and Safety

• Ethical/Environmental Impact

Considerations:

• Environmental

- Temperature Variation

- Humidity Changes

• Part Quality

• Power Supply Reliability - Voltage Regulator - Electrolytic Capacitor - Schottky Diode

• Sensor Reliability

• Microcontroller Reliability

• RF Chips Reliability

• Rationale for selection of components– Microcontroller

• Computational Requirements• Memory Capacity• Ethernet Capability for base station

– RF Module• Transmission Strength

– Sensors• Type of detection• Detection Range

– General Concerns• Weather Conditions

• Clock Speed– Rabbit Micorcontroller

• Web server provides access to information• Parking vehicles in designated places• RCM2100 RCM2110 RCM2120 RCM2130

Microprocessor Rabbit 2000™ at 22.1 MHz• RCM3000 RCM3010 Microprocessor Rabbit

3000 at 29.4 MHz

– Atmel Micorcontroller• 8-bit AVR Microcontroller Up to 16 MHz

• Mostly for processing data– Rabbit Micocontroller

• RCM2100 RCM2110 RCM2120 RCM2130 • Flash 512K 256K 512K 256K • SRAM 512K 128K 512K 128K• RCM3000 RCM3010• Flash 512K (2 x 256K) 256K• SRAM 512K 128K

– Atmel Micorcontroller• 8-bit AVR Microcontroller• Flash 64K • SRAM 4K

• Rabbit Micorocontroller

– RCM2100 RCM2110 RCM2120 RCM2130

10Base-T, RJ-45, None 2 LED’s

– RCM3000 RCM3010

10Base-T, RJ-45, 2 LED’s

• Amtel Microcontroller

– 8-bit AVR Microcontroller

None

• Microcontroller– Needs Ethernet capability– Speed is not a concern due to the interface

with humans– Overall, chose RCM 3010 for Ethernet

capabilities, memory storage, and performance to cost ratio

• Initially needed pins for each sensor– After midterm review, this was changed

• After comparing the Atmel to the Rabbit for the base station use, the Atmel was chosen for the Transmitter Module

• Transmission– Ability to be used in an inhospitable

environment– Ability to use different frequencies

• Reception– Ability to distinguish noise from actual signals– Ability to reproduce data from received signal

• Detection Type– Inductive– Infrared– Ultrasonic

• Detection Range– Needs to be able to detect vehicles at variable

distances– Needs to be confined to a predetermined area

so as not to detect vehicles in other parking places

• Most components will be subject to the climate of the garage– Industrial vs. Commercial

• Wider range vs. More cost

• Price of Installation– Upfront cost vs. Long-term cost

• Power Consumption– Slow change in environment being monitored

• Monitoring parking spaces to detect occupancy– U.S. Patent #6,694,259

• Using image processing to detect occupancy– U.S. Patent #6,559,776

• Using a plurality of sensors to monitor multiple spaces– U.S. Patent #6,292,110

• Using infrared sensors to detect occupancy– U.S. Patent #6,266,609

• Using GPS coordinates to detect occupancy

• All could cause problems under doctrine of equivalents, while the second could be a literal infringement

• Displaying parking occupancy graphically– U.S. Patent #6,662,077

• Uses a GUI to display occupied storage cells

– U.S. Patent #6,502,011• Uses a GUI to display information on the web

• The first patent could cause a problem under the doctrine of equivalents

• The second patent would be a literal infringement

• Getting real time parking information– U.S. Patent #6,501,391

• Showing real time parking information “in the form of a textual listing, a graphical map, a video image, an internet web page or similar form”

• This would cause a literal infringement because we show real time parking information via a textual image on an internet web page

• Sensor Multiplexing– U.S. Patent #6,317,034

• The ability to hook many sensor lines up to one line (to be sent to a controller)

• Possible infringement under the doctrine of equivalents.

• Testing of Software– Ensure that the RF receiver is warmed up before sending

data– Warm the receiver by sending junk bytes– Multiple transmissions of data is done to avoid collisions.– Ensure that the RF output power level is FCC approved by

using appropriate resistor values.

• Safety Precautions– Voltage regulators get “hot” during operation, labels are

placed on all such components– The IC’s are sensitive to electrostatic, care should be taken

while handling such devices.– Schotky diodes are placed to protect the PCB’s from

reverse polarity.

• Documentation– User manual will contain instructions to install

each of the specific components for expansion.

– User manual will mention about parts which can become “hot” during operation

– User manual will document the functions of the LED’s in each of the modules for the technician to debug.

• Manufacture of PCB– PCB manufacturer’s use toxic and corrosive liquids – Improper handling of these liquids can lead to

corrosion of and permeation through unprotected flooring

– Circuit components contain harmful chemicals such as lead, cadmium and polychlorinated phenyls

• Solutions– Identify work practices and engineering changes that

reduce the risks.– Minimize releases and in turn reduce liability – Recycle the boards after their use

• Power consumption– Can be reduced by using the power down feature in

the RF modules– Putting components that are not in use in sleep mode

to reduce power consumption

• Shipping and Packaging– Substitute with Starchafoam, which is biodegradable– Usage of starch-packing-peanuts, which are nontoxic,

water soluble and eco-friendly.– Components should be packaged properly to avoid

user to come in contact with fissured IC’s and broken electrolytic capacitors.

• Recycling– Recycling can recover contaminants like copper and

other etched metals – Recycling reuses spent chemicals in wastewater

treatment process– Recycling can recover contaminants like copper and

other etched metals – Reduce waste by removing and recovering regulated

materials from the printed circuit boards – The reduction of hazardous waste helps facilities to

meet the requirements of waste reduction under RCRA, 40 CFR 262 and Executive Order (EO) 13148, Greening the Government Through Leadership in Environmental Management

• Packaging Design Considerations

• Schematic Design Considerations

• PCB Layout Design Considerations

• Software design Considerations

Receiver #5

Receiver #4

Receiver #3

Receiver #2

Receiver #1

Rabbit

Cat5 Cable

Sensor

Transmitter

Receiver

Cat5 Cable connecting Sensors and Transmitter

Example Floor Plan Layout:

Key:

• Package One : Sensor Packaging

• Will be mounted in front of each parking space, such that the ultrasonic sensors are directed towards the front of the car

Schematic Notes :

- All measurements in cm

- Jack on side of box is for Cat5 cable (RJ45 connector)

• Package Two : Transmitter Packaging

• Will house an RJ45 connection brick, the Atmel ATmega8515L, the Linx TXM-315/433-LC RF transmitter, and its own power supply (used to power Atmel, Linx, and sensors). External antenna is for RF transmission

• Will be mounted on post/wall of garage (many per each floor of garage)

Schematic Notes :

- All measurements in cm

- Jacks on front of box are for Cat5 cables (RJ45 connectors)

• Package Three : Receiver Packaging

• Will house Linx RXM-315/433-LC-S RF receiver

• Will be mounted on edge of garage (1 per garage floor) vertically above the Rabbit packaging

Schematic Notes :

- All measurements in cm

- Coaxial out on front has been changed to RJ-45 out

• Package Four : Rabbit Packaging

• Will house Rabbit 3010 and its own power supply (used to power Rabbit and RF Receiver

• Will be mounted directly below all of the receiver packages on ground floor of parking ramp

Schematic Notes :

- All measurements in cm

-Jack on side of box is for Cat5 cable (RJ45 connector)

- Coaxial in on front has been changed to RJ-45 in (similar to Transmitter packaging

Power Supply for Atmel & Receiver board

Transmitter Module

Receiver Module

Power Supply of Rabbit Microcontroller

Rabbit Module

• No right angles on the traces

• Place switching traces as far away as possible

• Larger Power and Ground traces

• Placed power supply together

• Related components as close together as possible

Atmel Layout

Receiver Layout

Rabbit Layout

• Capability to address each parking space

uniquely

- Assigning each transmitter a unique address

- Assigning each sensor an address

• Reliable RF transmission protocol

- No feedback from the receiver end

Rabbit Microcontroller• Protocol to ensure correct transfer of data

over the RF link• Capability to ensure dynamic updating and

display of the webpage and receive all the data from the RF link simultaneously

• Modularity: Capability to easily add/remove new sections of Parking Lot or new floors.

Atmel Microcontroller• Sensor echo response analysis to

correctly ascertain presence of a car

- Analyze sensor echo pulse width to make correct conclusion

• Protocol to ensure correct transfer of data over the RF link

- Sending extra junk bytes before actual data to warm up the RF link - Transmitting same data more than once - Transmitting checksum along with data

Atmel Microcontroller

• Capability to work correctly in all possible environments

- A sensor not working

- Removing adding sensors from the Atmel/Transmitter

module

• Continuous running of this system

• Success Criteria #1: Ability to detect the presence of a car using ultrasonic sensors– Car drives into parking spot, transmit light on

transmitter turns off and back on

• Success Criteria #2: Ability to modularize– Can add any of the four modules to design with little

installation hassle

• Success Criteria #3: Ability to scale up the project– Can be seen when we add an additional sensor, and

also when we add an additional transmitter & sensor

• Success Criteria #4: Ability to use the RF transmitter to transmit information from the microcontroller (Atmel) and use the RF receiver to receive this information and feed it to the Rabbit microprocessor for processing.– This can be seen when we pull a car into or out of a spot and

see the web server update its status

• Success Criteria #5: Ability to transmit the available parking spaces from the Rabbit to a web server via the Ethernet module and update this information in real time.– This can be seen when we pull a car into or out of a spot and

see the web server update its status

• Matt Downes– Hardware Debugging– Soldering and Packaging

• Stephen Osborn– Atmel Coding/Debugging– RF Debugging

• Anup R. Daniel– Schematic– Power Supply Design

• Pawanjit S. Chawla– Rabbit Coding/Debugging– RF Debugging

• OrCad Schematic and Layout

• PCB layout is critical for the success of the project

• PCB/Hardware debugging

• Interfacing with RF components

• Interfacing Atmel and Rabbit microprocessors

• More emphasis should be placed on the PCB layout.

• Multiple display boards in the garage

• Better RF antenna solution

• Add repeaters for better RF range/coverage area

• Modify design such that is easier to troubleshoot in the field