CMS:Children Monitoring System By: Mohammad Safar |Steven Smith

Failure and Redesign Old design: New Idea: Was too simple. Implemented and wasn’t practical. New Idea: Brief introduction. Four sub-systems for a more quality design. A) Sensor. B)Clip (Wearable). C) Router. D) Phone Software.

How will the devices work together

Presentation Flow Sub Devices explained. Detailed information of parts. Power consumption analysis. Progress. Testing. Demonstration.

Sensors: Purpose: Parts: Capture motion movements and relay the information to Device B (clip) Parts: Arduino Nano: We need the device to be light and convenient for use. PIR motion Sensors (Passive Infrared): Detects the motions and send the signals to the RF Transmitter. RF Transmitter: Receives the signal from the PIR sensor and sends it to the clip device. 9V Duracell Battery with a 600 mAH Value

Sensor The Design was made using fritzing application

Clip (Wearable Device) Purpose: Receive the motion signal. Read input from accelerometer. Relays sound to device C(Router). Arduino Uno: Needed to use the accelerometer shield. RF receiver: Receive signals from the motion sensor. Wireless Transceivers or RF Transmitters: Depending on if the small wireless transceivers will decide if we need to have a Router (Device C) or connect the clip device directly to the phone. Accelerometer: Capture shaking movements. Sound Sensor: Detects sounds: can be activated to relay an alarm if a sound if sound signals persisted for a specified amount of time. Used for crying detection when left alone.

Clip

Router Purpose: Arduino Uno + Wi-Fi shield. Relay information between the Phone Software and the clip device. Was needed because the Wi-Fi shield is too large to implement in the clip device. Depending on the Wireless transceiver we might not need this device. Arduino Uno + Wi-Fi shield. To establish Wireless connection with the paired Phone device. RF Transmitter/Transceiver: Transmit signals from and to the clip device.

Phone application Requirements: Android OS. Wireless connection. The phone will be paired wirelessly to either Device B or C (Clip or Router). Using the application the user can control which inputs and alarms to receive: Motion sensors input and assign an alarm to it. Accelerometer: Assign how many inputs in a specified amount of time to trigger an alarm or turn off the function completely. Sound sensor input: by turning this on the user can get alarms if the device detected a sound of a certain level for a specified amount of time.

Sensors (Detailed) The PIR motion sensor has: Operating voltage of 4.5 -20V. Capture angle 120 cone degrees 1-2 meters. According to spec sheet will test it to get confirm. Current 50uA.

Sensors (Detailed) RF Transmitter: RF Receiver: Operating voltage of 3-12V. Working Current 20-28 mA. Working Frequency 315-433 MHz. Distance up to 500m with sentivity to -103dBm RF Receiver: Operating Voltage 5 VDC. Static current 4 mA. Has same working frequency as the Transmitter

Clip Device (Detailed) Wireless Transceiver: Operating voltage of 1.9-3.6 Either connect to 5V pin with voltage divider or 3.3V pin. Current analysis: 11.3-13.5 mA while transmitting/receiving data. 25uA while on standby. 900nA while in power down. Range is 80 meters (282 ft). 2.4 GHz antenna and data rates if (250 kbps , 1 Mbps , 2Mbps).

Clip Device (Detailed) Sparkfun Accelerometer Operating Voltage of 1.95 – 3.6V. Either connect to 5V pin with voltage divider or 3.3V pin. Current consumption: 40uA in measurement mode , 0.1 uA in standby. High resolution measurements. Can set acceleration on any axis when it exceeds a user set level.

Clip Device(Detailed) Sparkfun Sound Sensor: Operating voltage of 3.5-5.5 V Current consumption 240 uA in detection mode. Can control sensitivity for detection. 9V Lithium batteries: 600 mAh. Rechargeable. To power up Arduino borads.

Leds and buzzers (Testing only) To know if the device is detecting or receiving signals. Buzzers: Using them for alarms until the Phone application is built.

Current Consumption All of the calculation are calculated while the device is working standby consumption is much lower. Sensor PIR Motion Sensor 50 uA RF Transmitter 28 mA Total 28.05 mA Battery life of 600 mAh 15 hrs Clip Device RF Receiver 4 mA Wireless Transceiver 13 mA Sparkfun Accelerometer 40 uA Sparkfun Sound detector 240 uA Total 17.280 mA Battery life of 600 mAH 24 hours

Progress Planning Progress report Week of Planned 31 Aug Tried RF tags with card reader 7 Sept Scrapped Idea 14 Sept Came up with new design and added more functions 21 Sept Complete Accelerometer and sound detector 28 Sept Test wireless transceiver and decide if we want to use the Wi-Fi shield 5 October Design the phone application 12 October Test individual parts and them paired together 19 October Assemble device for final packaging 26 October Design the cases 2 November Final packaging complete 9 November Work on the video

Testing by subsystems (Sensor) PIR Sensor: Make sure it covers the intended area in our case we are aiming for doorways this will be tested by making a human child pass through doorways in everyway we can think of (walking, running, jumping, crawling) and check the signal acquisition. Transceiver/Receiver: First we want to make sure that the receiver receives the signal from the PIR sensor. We also want to make sure that the alarm reacts only to the child wearing the clip device instead of anyone who passes through the PIR sensor. We are going to test the power to the signal vs the range and make document the threshold of when the child is in range of the PIR sensor and make the alarm only activates on that threshold.

Testing by subsystems (Clip device) Receiver (covered in previous slide) Accelerometer: Test if the accelerometer can detect sudden jolts of movement from the wearable device. Making sure the accelerometer can detect “free falling” conditions in case child falls Sound detector: Testing the sensitivity and acquire the best required input for capturing the child’s voice without interference from other noise. Wireless transceiver: Check connectivity with the paired phone device. Check range vs connectivity to make sure information aren’t lost

Testing the whole system After building the device we will test the prototype to see if all the inputs and outputs matches the required design. Check connectivity between the whole network of subsystems.

What we are going to demonstrate What we have so far! Completed the sensor paired with an LED to know when a PIR reading is acquired. Completed the test code of the sensor. Completed The RF Receiver instead of relaying the information received to the phone device we put an LED and buzzer to confirm the receive of signal. Completed the test code for the receiver.

Sensor Test Circuit:

Sensor (test code)

Receiver Test Circuit:

Receiver (test code)

Demonstration

Questions and suggestions! Any help and ideas are appreciated!