Modeled Car With Ejector Seat ECE 445 Team 78 Xiaoyi Chen, Xiangjian Gao Spring 2016

Introduction  Our project is designed to avoid death of car crashes.  Airbags cannot save lives in many conditions such as very high speed crash  Eject people out to a safe place before the car crashes

Features  Eject people out of the car when the car's relative speed and distance exceeds threshold which will cause death  People with different weights are ejected to the same height

Block Diagram

 1. Power System  2. Mechanical Design  3. Detection System  4. Ejection System

Power System

110V AC voltage to 12V DC voltage AC to DC converter 12V to 5V Voltage Regulator

Power System

Mechanical Design Top view Springs Pillar

Mechanical Design Side View Idler Sprocket Sprocket No. 25 Chain Motor Fixed point

Mechanical Design Solenoid Pin Solenoid Lock Position Metal

Mechanical Design Pillar When Ejection seat has been ejected, Top board would fall off. We use two pillars in each side to hold top board. This could avoid collision damage.

Detection System Microprocessorultrasonic distance sensor Trig Echo

Start Distance<=1m && Speed>=1 m/s? Distance<=1m && Speed>=1 m/s? Output signal to solenoid Yes No solenoid

Ejection Height Control MicroprocessorLoad sensor

Get weight Start Calculate step Output to motor k - spring constant k=2500N/m h - desired ejection height, h=0.5m C - circumference of motor, C=16.35cm aps - angle per step, aps=0.018°

Motor provides ejection force Stepper motorMotor driver

Motor provides ejection force Idler sprocket Sprocket

Filter Design Filter is a device or process that removes some unwanted components or features from a signal. Slope Gain ω/ω0ω/ω0 ω/ω0ω/ω0 Passband ω/ω 0 = f c /f = 100Hz / 1KHz =

Filter Design =1 R4 = 0, IN- to Vout would be shorted Nothing would pass to R3, So we just set R3 = 0 Fc = 100 Hz 1. 2.

Bench Test for Filter design Yellow waveform: 1KHz Frequency 5Vpp 2.5V offset Sin wave Green waveform: Output waveform

Filter Design Change Scope: Green waveform is a sin waveform too

Could improve  1. Attaching springs to ejection deck.  2. More powerful solenoid.

Future work  1. Eject to backward & right direction  2. Add parachute on ejection seat  3. Work on a real car  4. Open top of real car.  5. More accurate deadly situation  6. Power system improvement.

Question s?

 Thank you!