CARS Cellular Automotive Remote System Abhishek Jain Mike Charogoff Matt Lasek Nguyen Le Blair Harness

Objective Effectively work in a group to produce a working prototype of a cellular automotive remote system. At expo the demonstration system will send and receive information via a cellular phone.

Functionality Resembles OnStar More universal, many more and different convenience features. Through CARS the user can control: Starter Security system Heat and cooling system

Functionality CARS obtains and sends information about: Temperature Theft Vehicle location Accidents

Optional Features User obtains information via voice messages Control movement of vehicle (prototype) Gives information of vehicle distance from user Information received from car on a terminal PC or microcontroller

C.A.R.S.- System Overview Audio Amp Misc.Analog Inputs (Temp., Accelerometer) GPS Misc. Digital Inputs (Bumper, Optical Encoders, Door Switch,..etc. Speaker, Microphone, and Solenoids MCU (W/ ADC on-board) Solenoid Driver, DAC and Audio Amp Misc. Digital Outputs Heater, Door L/U, …etc. Cellular Phone Home or Cellular Phone Audio Amp MCU (W/ ADC on-board) Memory (RAM or Serial EEPROM) LCD or Serial link to PC Memory (RAM or Serial EEPROM) Vehicle“Home” Wireless Solenoid Driver, DAC and Audio Amp Alternate implementation does Not require solenoids, DAC, Or Speaker on Home system. Speaker, Microphone, and Solenoids

Functionality Overview Vehicle-based system MCU Digital Inputs GPS Door Switch Bumper Switch *Optional Feature Optical Encoders *Optional Feature ADC (For analog inputs) Microphone (Audible tones are amplified and converted Temperature Sensor Accelerometer (used to detect Collision) Digital Outputs Door Locked/U (LED used to represent door lock or hood release control) Auto-Dial Control (These signals feed a driver circuit and solenoids) Heater (Lamp used to represent heater control and create heat for temp. sensor) Lights or horn Indicator (LED used to represent Headlamps or horn) Motor Control *Optional Feature DAC (For analog outputs) Analog Tone (Amplified and fed to speaker in order to send data) *Voice is optional

Functionality Overview “ Home”-based system MCU ADC (For analog inputs) Microphone (Audible tones are amplified and converted to digital representation) Digital Outputs LCD (or Serial Bus) Auto-Dial Control (These signals feed a driver circuit for solenoids) DAC (For analog outputs) Analog Tone (Amplified and fed to speaker in order to send data)

Preliminary Board Layout

Preliminary Board Layout (And Mechanical Design of OPTIONAL Mobile Platform)

Tone Reception and Decoding Audio Amp Speaker, Microphone, and Solenoids MCU PIC? 68HC1X? (W/ ADC on-board) Solenoid Driver, DAC and Audio Amp Cellular Phone Principle of Operation 1.Audible tones generated by the phone are converted to an electrical signal by the microphone (transducer). 2.This electrical signal is amplified and fed to an ADC. 3.The digitized signal is decoded. The specific decoding method has yet to be established, but one possible method would involve calculating the number of samples between zero crossings (or peak values). This number (n) would be unique for tones of different frequencies if the sample rate is adequate (> ~ 30k/sec). 4.After decoding, the Microcontroller executes the issued command (i.e. start vehicle, Lock doors, Unlock doors, …etc.). (1) (2) (LM380?) (3) (4)

Audio Amp Speaker, Microphone, and Solenoids MCU PIC? 68HC1X? (W/ ADC on-board) Solenoid Driver, DAC and Audio Amp Cellular Phone Principle of Operation: (Very much the opposite of tone reception process) 1.The phone number of the “Home” station is stored in the cell phone so that the auto-dial function may be used. Two Solenoids are positioned (variable to accommodate various models) to push the appropriate buttons (thus calling the base). 2.The Vehicle-based system then waits for the Home station to transmit an initialization tone to be sure that it has “picked-up”. (Alternatively, Vehicle-based system waits for ringing to stop followed by a delay. This simplifies Home system, but may sacrifice reliability and features). 3.Now the Vehicle-based system may transmit by converting its stored data into an analog signal (via a DAC). 4.This analog signal is amplified (LM380/LM386?) and converted into sound by way of a small speaker (transducer). Design Considerations: Frequency response of Microphone and speaker. Solenoid voltage/power requirement (12V?). How standard is auto-dial on current generation cell phones? (Audio) “cross-talk” between speaker and microphone. How to hang-up? Another solenoid? How much data may be stored on memory device of choice? (1) (2) (3) Tone Creation and Transmission Stored Data EEPROM? SRAM? FLASH? (4)

Solenoid Control Principle of Operation: A digital signal is used to control the driver circuit. Driver circuit consists of discrete components or an IC. Current spikes and other large, inductive load concerns must be analyzed. Solenoid only needs to be energized for a fraction of a second in order to push the appropriate button. Overall power use should be relatively small. MCU Solenoid Driver (L294/295 ?) Solenoid Cell Phone (1) (2) (3)

Digital Inputs GPS: Take existing GPS device to track route of car. Data consisting of longitude, latitude, and possibly distance or speed of car sent via a serial data link to the microprocessor. Door Indictor: Notifies home if user forgets to lock car door. Implemented by a push-button switch, which will be pushed if the door is locked and released if it is unlocked. Bumper Switch (Optional): Use spring-loaded switch so that when demonstration car hits an object the switch will be pushed. This will cause the car to change directions and avoid being stuck in one spot. Optical Encoder (Optional): Device will measure certain aspects of demonstration car such operating speed, direction and will relay this information, in the form of digital pulses, to the microprocessor. Microprocessor will then use this data to control the car’s motion. Optical Encoder (Optional) GPS Door Indicator MCU (W/ ADC on-board) Bumper Switch (Optional) To Rest of Block Diagram

Temperature Sensor: A thermocouple or RTD (resistance temperature detector) will be used to obtain a temperature reading inside and/or outside car. The measurement data will be sent to the user when the user gives the appropriate command. Anti-Theft Device: A vibration sensor, possibly piezoelectric, will be used to detect any disturbances to the car. If a disturbance is detected, the data will be sent to the microprocessor which will alert the user. Accident Alarm: Consists of a combination of devices that notifies emergency personal if the car is in an accident and gives them information about the location and severity of the accident. This will be done by using GPS (previously mentioned), accelerometer, and voice recordings. The accelerometer will give information about the magnitude of the accident and from this data will determine the severity of the crash. Temperature Anti-Theft Device MCU Accident Alarm To Rest of Block Diagram Analog Inputs

Heater/Air Conditioner: Device will allow the user to warm/cool the interior of the vehicle from home by use of cell phone Heater will be implemented by use of a lamp which will be activated by a switch (MOSFET, BJT). Air conditioner can be realized by using a fan which would also be initiated by a switch. LED’s: The realization of the peripherals such as activating the door lock/unlock, starter, headlamps, and horns used as the vehicle locater will be demonstrated using an array of LED’s. Motor Control (Optional): This device allows control of the demonstration car’s motion. It does this by sending data to the car’s motor and wheels to control the car’s speed and direction. Auto-Dial Control: This device consists of a solenoid which pushes buttons on the cell phone so that it can transit data. Digital Outputs MCU To Rest of Block Diagram Heater Air Conditioner Door Unlock/Lock Lights Motor Control (Optional) Auto-Dial Control

Division of Labor Abhishek Jain-Digital Outputs Matt Lasek/Nguyen Le-Inputs (excluding audio features) Mike Charogoff –Audio Input/Output Blair Harness-Programming, Micro- controller

Risks and Contingency Plans Areas of risk: Microprocessor  Learning hardware/software use of micro controller  Shouldn’t be an issue, several group members are familiar with technology Button pusher  Ability to push (and possibly hold for speed dial) buttons  Number of buttons we will need to push  Plan on using solenoids for pushing buttons  Multiple fixed solenoids vs single solenoid on servo drive Audio quality needed for tone recognition  Shouldn’t be a problem  Add filters/amplification if needed

Risks and Contingency Plans Areas of risk: Voice reply (optional)  Strings of digits sent back – requires ‘base station’ module  If possible, add voice reply Time vs quality considerations Number of messages needed  Storage requirements Accident alert thresholds  Should not report accident under hi-performance vehicle acceleration  Will need thresholds  Might have to setup differently for different cars

Schedule

Summary CARS convenience features include: Remote start/idle system Heat/Cool the interior of your car Lock/Unlock your car doors Anti-Theft System Accident Alarm System Temperature Sensor GPS

Questions?