Motion Detecting Workstation Theodore Shinners Kevin Schmitz University of Iowa: Embedded Systems Spring 2011

Hardware Overview Four Motion Control Sensors Three Solid State Relays spliced in extension cords

Zilog ZMOTION Detectors

Zilog ZMOTION Detectors Cont Pins 1,8 are GND Pins 2,7 are Vcc: Device Uses 3.3V. – Required a simple step down from the 5V output – Used a Sharp voltage regulator Pin 6 is not used, set to Vcc Pin 5 is the output, pulled low with motion Pin 4 is analog input for sensitivity, set to 1.4 V for medium sensitivity Pin 3 is analog input delay, set to.2V for a 5 sec signal

Solid State Relay

SSR Continued SSR has 5V control and 5A 240 VAC/VDC load Standard 3 wire extension cords were cut apart Relay was soldered on the live wire Output from circuit above wired to control When the MCU output pin for associated relay goes high whatever is plugged into the extension cord is turned on

Software Overview Four motion sensors inputs to MCU All pulled up, when one goes low: – Determine what sensor was tripped – Look for any patterns – Determine the current output state of associated relay output – Change the output accordingly Constant Sampling for motion, delays once found

Software Example pin = PINC; pin = pin & 0b ; //read in inputs if(pin != 0b ){//if a sensor is low //Sensor 1 if(pin == 0b ){ //if it is the first sensor _delay_ms(2000);//wait and look for the pin = PINC;//”all on” condition pin = pin & 0b ; if(pin == 0b ){ temp2 = 0b ; //three output pins will be on }

Software Example Cont. else{ temp = out & 0b ; //otherwise only deal with the 1 st relay if(temp == 0b ){ temp2 = out & 0b ; //if on turn off } if(temp == 0b ){ temp2 = out | 0b ; //if off turn on } } out = temp2;//send the output PORTB = out; _delay_ms(5700);//wait for delay to run out } //end sensor 1

Motion Description 4 Motion Detectors Placed Horizontally across a board with line of sight focused with a physical shield Detectors 1-3 individually control output hardware 4 th detector controls output hardware components 2 and 3 1 st motion is to simply wave your hand over a sensor – One pass over the sensor will turn the component on – The next will turn it off

Possible Motions 2 nd motion is to wave your hand from left to right across all 4 sensors. – This will turn on all 3 output hardware components 3 rd motion is to wave your hand in the opposite direction across all 4 sensors. – This will turn those same components off

Real World Applications Reduction of Power Consumption Lighting Control Limited Mobility Assistance Personal Use, plug in anything User Interfacing, motion control on desktop PCs, etc

Possible Improvements Program More Motion Patterns – ie (3,2,1,4 makes all devices blink on and off) Improve Software to avoid problems with long delays from motion controls Additional output hardware – Workstation can control anything powered by an outlet