Saturday, June 21, 2014

GPS Location Sensing with the Arduino Mega

This project shows how to get location in latitude and longitude coordinates using an electronic circuit built with the Arduino Mega 2560 and the ITEAD GPS Shield v1.1 . If you want to see how to do GPS location sensing with the Arduino Uno and an LCD display check out my other blog.

The GPS shield has a GPS antenna connected. This is very important as you can't get a location fix if you don't have an antenna.

Using this circuit I got a location fix indoors on the ground floor of a 2 story house in 1 to 2 minutes. Outdoors it got a fix in about 30s or less. Accuracy was very good, to within 10-20ft initially, and improving the longer you leave it (it gets a new reading every second.

The wiring of this diagram is straightforward. First you should set the voltage switch on your GPS shield to 5v before you power it on and connect it up. There is also a 3.3v setting, but for our circuit we are using the Arduino Mega 2560 so the voltage setting I used is 5v. Next you need to set the jumpers for Rx (receive) and Tx (transmit) on the GPS shield. I set my GPS Rx to pin 6 and GPS Tx to pin 5. I wanted to receive the output of this circuit on my computer so I needed the default hardware serial interface for that. To communicate with the GPS shield I used the mega hardware serial interface 1. So I wired GPS Rx pin 6 to Mega Serial1 Tx1 pin 18, and GPS Tx pin 5 to Mega Serial 1 Rx1 pin 19. Using this circuit I was able to get a location fix even inside a house on the ground floor of a 2 story house. If used outside with a clear view of the sky it will get a GPS fix even faster.

You will need TinyGPS to run the sketch I used. Specifically you will need the TinyGPS.cpp and TinyGPS.h files to run this. I just dropped them in the same folder as the Arduino sketch and then when I loaded the sketch the Arduino IDE automatically found these two files and compiled and uploaded them with my sketch to the Mega for testing.

Below is a screenshot of the Arduino IDE serial console showing output from this sketch running. The GPS latitude / longitude coordinates each have a precision of 6 decimal places.

Below is the Arduino sketch I used for testing:

#include "TinyGPS.h"

TinyGPS gps;

#define GPS_TX_DIGITAL_OUT_PIN 5
#define GPS_RX_DIGITAL_OUT_PIN 6

long startMillis;
long secondsToFirstLocation = 0;

#define DEBUG

float latitude = 0.0;
float longitude = 0.0;

void setup()
{
  #ifdef DEBUG
  Serial.begin(19200);
  #endif
  
  // Serial1 is GPS
  Serial1.begin(9600);
  
  // prevent controller pins 5 and 6 from interfering with the comms from GPS
  pinMode(GPS_TX_DIGITAL_OUT_PIN, INPUT);
  pinMode(GPS_RX_DIGITAL_OUT_PIN, INPUT);
  
  startMillis = millis();
  Serial.println("Starting");
}

void loop()
{
  readLocation();
}

//--------------------------------------------------------------------------------------------
void readLocation(){
  bool newData = false;
  unsigned long chars = 0;
  unsigned short sentences, failed;

  // For one second we parse GPS data and report some key values
  for (unsigned long start = millis(); millis() - start < 1000;)
  {
    while (Serial1.available())
    {
      int c = Serial1.read();
//      Serial.print((char)c); // if you uncomment this you will see the raw data from the GPS
      ++chars;
      if (gps.encode(c)) // Did a new valid sentence come in?
        newData = true;
    }
  }
  
  if (newData)
  {
    // we have a location fix so output the lat / long and time to acquire
    if(secondsToFirstLocation == 0){
      secondsToFirstLocation = (millis() - startMillis) / 1000;
      Serial.print("Acquired in:");
      Serial.print(secondsToFirstLocation);
      Serial.println("s");
    }
    
    unsigned long age;
    gps.f_get_position(&latitude, &longitude, &age);
    
    latitude == TinyGPS::GPS_INVALID_F_ANGLE ? 0.0 : latitude;
    longitude == TinyGPS::GPS_INVALID_F_ANGLE ? 0.0 : longitude;
    
    Serial.print("Location: ");
    Serial.print(latitude, 6);
    Serial.print(" , ");
    Serial.print(longitude, 6);
    Serial.println("");
  }
  
  if (chars == 0){
    // if you haven't got any chars then likely a wiring issue
    Serial.println("Check wiring");
  }
  else if(secondsToFirstLocation == 0){
    // still working
  }
}


Hope you found this useful. Let me know if you create any cool enhancements to it. Have fun!

If you need any of the parts for this projects you can find them below:

Saturday, June 7, 2014

GPS Location Sensing with the ITEAD GPS Shield and Arduino Uno

Location is a valuable input for many applications. In this project I use the ITEAD GPS Shield v1.1 with a GPS antenna , an Arduino Uno , and an LCD Display to sense location in terms of latitude and longitude coordinates.

With this setup I was able to acquire lat / long coordinates outdoors with a clear view of the sky in 23s to 32s with an average of 28s. Indoors on the bottom floor of a 2 story house I was able to get a location in 61s to 140s with an average of 101s from time of power up to time of first GPS lat / long coordinate acquisition. With this circuit the longer it is given the more accurate the reading. Typically I found the first reading within a hundred or so feet and given more time it would get down to a few feet accuracy.

Below is the picture of the complete circuit.

The wiring of the circuit is fairly straightforward. There are two parts. The first is how to connect the GPS shield. It connects easily on top of the Arduino Uno so thats no problem. You will also need to set the jumpers for the GPS Rx (receive) pin 7 and GPS Tx (transmit) pin 6 parts of the serial interface.

Note that later on in the sketch for the Arduino code you will see the Uno Rx pin is 6 and Uno Tx pin is 7. This is because the Uno (Tx) transmits to the GPS (Rx) on pin 7 and conversely the Uno (Rx) receives from the GPS (Tx) on pin 6.

The second part of the wiring is the LCD display. Your wiring may vary depending on the display you have, so check its instructions. For my wiring I used the hookup below:

 LCD Pin Connect to
 1 (VSS) GND Arduino pin*
 2 (VDD) + 5v Arduino pin
 3 (contrast)  2.2k resistor to GND
 4 RS Arduino pin 12
 5 R/W Arduino pin 11
 6 Enable Arduino pin 10
 7 No connection 
 8 No connection 
 9 No connection 
 10 No connection 
 11 (Data 4) Arduino pin 5
 12 (Data 5) Arduino pin 4
 13 (Data 6) Arduino pin 3
 14 (Data 7) Arduino pin 2
 15 Backlight +
  1.5k resistor to Arduino pin 13
 16 Backlight GND GND Arduino pin*

I found this blog helpful in wiring my display.

Make sure you have a GPS antenna. I was not able to get a location fix without one.

I used a small 9v battery to power the circuit. This was fine for testing the acquisition time in a variety of locations. If you intend to run this circuit for longer periods of time you may need a more powerful power supply.

You will need TinyGPS to run the sketch I used. Specifically you will need the TinyGPS.cpp and TinyGPS.h files to run this. I just dropped them in the same folder as the GPS_LCD_Display.ino Arduino sketch and then when I loaded the sketch the Arduino IDE automatically found these two files and compiled and uploaded them with my sketch to the Uno for testing.

Below is the Arduino sketch I used for testing:

#include <SoftwareSerial.h>
#include <LiquidCrystal.h>

#include "TinyGPS.h"

TinyGPS gps;

int unoRxPin = 6; // connected to Tx pin of the GPS
int unoTxPin = 7; // connected to Rx pin of the GPS
SoftwareSerial ss(unoRxPin, unoTxPin);

LiquidCrystal lcd(12, 11, 10, 5, 4, 3, 2);
int backLight = 13;    // pin 13 will control the backlight

long startMillis;
long secondsToFirstLocation = 0;

void setup()
{
  ss.begin(9600);
  
  pinMode(backLight, OUTPUT);
  digitalWrite(backLight, HIGH); // turn backlight on. Replace 'HIGH' with 'LOW' to turn it off.
  lcd.begin(20,4); // columns, rows.  use 16,2 for a 16x2 LCD, etc.
  lcd.clear();  // start with a blank screen
  
  startMillis = millis();
}

void loop()
{
  bool newData = false;
  unsigned long chars = 0;
  unsigned short sentences, failed;

  // For one second we parse GPS data and report some key values
  for (unsigned long start = millis(); millis() - start < 1000;)
  {
    while (ss.available())
    {
      int c = ss.read();
      ++chars;
      if (gps.encode(c)) // Did a new valid sentence come in?
        newData = true;
    }
  }

  if (newData)
  {
    // we have a location fix so output the lat / long and time to acquire
    if(secondsToFirstLocation == 0){
      secondsToFirstLocation = (millis() - startMillis) / 1000;
    }
    
    lcd.clear();  // start with a blank screen
    
    float flat, flon;
    unsigned long age;
    gps.f_get_position(&flat, &flon, &age);
    lcd.setCursor(0,0);           // set cursor to column 0, row 0 (the first row)
    lcd.print("Lat=");
    lcd.print(flat == TinyGPS::GPS_INVALID_F_ANGLE ? 0.0 : flat, 6);

    lcd.setCursor(0,1);
    lcd.print("Long=");
    lcd.print(flon == TinyGPS::GPS_INVALID_F_ANGLE ? 0.0 : flon, 6);

    lcd.setCursor(0,2);
    lcd.print("Acquire Time=");
    lcd.print(secondsToFirstLocation);
    lcd.print("s");
  }
  
  if (chars == 0){
    // if you haven't got any chars then likely a wiring issue
    lcd.setCursor(0,0);           // set cursor to column 0, row 0 (the first row)
    lcd.print("No GPS: check wiring");
  }
  else if(secondsToFirstLocation == 0){
    // if you have received some chars but not yet got a fix then indicate still searching and elapsed time
    lcd.clear();  // start with a blank screen

    long seconds = (millis() - startMillis) / 1000;
    
    lcd.setCursor(0,0);           // set cursor to column 0, row 0 (the first row)
    lcd.print("Searching ");
    for(int i = 0; i < seconds % 4; ++i){
      lcd.print(".");
    }
    
    lcd.setCursor(0,1);
    lcd.print("Elapsed time:");
    lcd.print(seconds);
    lcd.print("s");
  }
}

Hope you found this useful. Let me know if you create any cool enhancements to it. Have fun!

Friday, May 2, 2014

Propane Gas Sensor Using the Arduino Uno

In this latest project I use the MQ6 propane gas sensor with the Arduino Uno to sense propane gas concentration in the air.

This sensor has a heater that requires about 150mA for 90s to take a reading. The Uno can't supply this current so I use a KA278R05 voltage regulator to provide it, with a 12v DC power supply providing the input power for the voltage regulator. The KA278R05 has an enable pin which I drive high using digital pin 8 of the Uno to enable the sensor for the 90 seconds it needs to be on in order to take a stable reading. I read the voltage level signal output of the MQ6 each second and the final stable value right at the 90s point after activating the sensor using analog input pin 0.

The schematic for the circuit I used:

The breadboard layout using the great tool from Fritzing:

The first set of results from clean air (no propane) graphed in excel. Here the measurement stabilized at around 256 after 90s:

The second set of results from air with a bit of propane graphed in excel. I put the sensor inside a grill with the lid closed and gave a small puff of propane, and without any flame. I recommend extreme caution if you try this. Just a tiny puff of propane, and in an outside area with good ventilation is how I did it. Have all the circuitry except the sensor outside the grill area. With this test the measurement stabilized at around 739 after 90s, which is almost 3 times higher than with clean air. Keeping in mind this was a very small puff of propane, this sensor is very sensitive:

Below is the sketch I used to drive the Uno for this test. I use a simple finite state machine to manage the state of the sensor.

#define MQ6_POWER_ON_DIGITAL_OUT_PIN 8
#define MQ6_LP_GAS_LEVEL_MEASURE_ANALOG_IN_PIN   0
#define MQ6_HEATER_TIME_MILLIS 90000
#define MQ6_SAMPLE_PERIOD_MILLIS 1000

int lpGas;

typedef enum {
  ST_MQ6_OFF,
  ST_MQ6_CYCLE_0_HIGH,
  ST_MQ6_DONE
} MQ6_STATE;

MQ6_STATE mq6State = ST_MQ6_OFF;

unsigned long mq6SwitchTimeMillis;
unsigned long mq6NextReadingTimeMillis;
unsigned long lpGasStartTimeMillis;
unsigned long startMillis;

//-----------------------------------------------------
void setup(){
  Serial.begin(19200);
  
  pinMode(MQ6_POWER_ON_DIGITAL_OUT_PIN, OUTPUT);
  
  startMillis = millis();
  
  // start 10s after power up
  lpGasStartTimeMillis = 10000; 

  // print headers for CSV output
  Serial.print("Seconds");
  Serial.print(",");
  Serial.println("LP Gas Level");
}

//-----------------------------------------------------
void loop(){
  readLPGas();
}

//-----------------------------------------------------
// uses a simple finite state machine to manage states of the MQ6 sensor
void readLPGas(){
  switch(mq6State){
    case ST_MQ6_OFF :
    {
      if(millis() > lpGasStartTimeMillis){
        digitalWrite(MQ6_POWER_ON_DIGITAL_OUT_PIN, HIGH);

        mq6State = ST_MQ6_CYCLE_0_HIGH;
        mq6SwitchTimeMillis = millis() + MQ6_HEATER_TIME_MILLIS;
      }
      break;
    }

    case ST_MQ6_CYCLE_0_HIGH :
    {
      if(millis() > mq6NextReadingTimeMillis) {
        lpGas = analogRead(MQ6_LP_GAS_LEVEL_MEASURE_ANALOG_IN_PIN);

        Serial.print((millis() - startMillis)/1000);
        Serial.print(",");
        Serial.println(lpGas);

        mq6NextReadingTimeMillis = millis() + MQ6_SAMPLE_PERIOD_MILLIS;
      }

      if(millis() > mq6SwitchTimeMillis){
        digitalWrite(MQ6_POWER_ON_DIGITAL_OUT_PIN, LOW);

        mq6State = ST_MQ6_DONE;
      }
      
      break;
    }

    case ST_MQ6_DONE :
    {
      break;
    }
  }
}

//-----------------------------------------------------

You can find a PCB breakout for this sensor if you are ready to create something more polished.

Let me know if you build any cool enhancements to this. Have fun!

Saturday, March 29, 2014

CO (Carbon Monoxide) Gas Sensor Using the Arduino Uno

This simple project uses the Arduino Uno and the MQ7 Gas Sensor to sense the concentration of CO (Carbon Monoxide) in the air. The MQ7 requires a heater voltage that cycles between 5v (60s) and 1.4v (90s), drawing approximately 150mA at 5v which exceeds the power capacity of the Uno, so I use the KA278RA05C adjustable voltage regulator to drive this. The default voltage of the KA278RA05C with Vadj (pin 4) disconnected is 5v which serves for the heater high voltage part of the cycle. I use a 50k potentiometer to adjust the voltage down to 1.4v for the heater high voltage part of the cycle. I use an LH1546 optical solid state relay to switch the adjustable voltage of the potentiometer on for the 1.4v heater low voltage. Pin 8 on the Arduino Uno drives the optical solid state relay and when high turns the relay on, adjusting the voltage of the regulator down to 1.4v. When this pin is low it turns off the relay causing the regulator to go back up to 5v. Analog pin 0 on the Arduino Uno is used to sense the voltage level out of the MQ7 which serves to measure the concentration of CO (Carbon Monoxide) in the air. Below is the diagram of the circuit on Fritzing.

Below is the actual circuit:

Below is the Arduino Uno sketch used:

#define VOLTAGE_REGULATOR_DIGITAL_OUT_PIN 8
#define MQ7_ANALOG_IN_PIN 0

#define MQ7_HEATER_5_V_TIME_MILLIS 60000
#define MQ7_HEATER_1_4_V_TIME_MILLIS 90000

#define GAS_LEVEL_READING_PERIOD_MILLIS 1000

unsigned long startMillis;
unsigned long switchTimeMillis;
boolean heaterInHighPhase;

void setup(){
  Serial.begin(19200);
  
  pinMode(VOLTAGE_REGULATOR_DIGITAL_OUT_PIN, OUTPUT);
  
  startMillis = millis();
  
  turnHeaterHigh();
  
  Serial.println("Elapsed Time (s), Gas Level");
}

void loop(){
  if(heaterInHighPhase){
    // 5v phase of cycle. see if need to switch low yet
    if(millis() > switchTimeMillis) {
      turnHeaterLow();
    }
  }
  else {
    // 1.4v phase of cycle. see if need to switch high yet
    if(millis() > switchTimeMillis) {
      turnHeaterHigh();
    }
  }
  
  readGasLevel();
  delay(GAS_LEVEL_READING_PERIOD_MILLIS);
}

void turnHeaterHigh(){
  // 5v phase
  digitalWrite(VOLTAGE_REGULATOR_DIGITAL_OUT_PIN, LOW);
  heaterInHighPhase = true;
  switchTimeMillis = millis() + MQ7_HEATER_5_V_TIME_MILLIS;
}

void turnHeaterLow(){
  // 1.4v phase
  digitalWrite(VOLTAGE_REGULATOR_DIGITAL_OUT_PIN, HIGH);
  heaterInHighPhase = false;
  switchTimeMillis = millis() + MQ7_HEATER_1_4_V_TIME_MILLIS;
}

void readGasLevel(){
  unsigned int gasLevel = analogRead(MQ7_ANALOG_IN_PIN);
  unsigned int time = (millis() - startMillis) / 1000;
  
  Serial.print(time);
  Serial.print(",");
  Serial.println(gasLevel);
}



The screenshot below shows the CSV data points of time in seconds against the MQ7 output voltage graphed into Excel.

The point at which to read the MQ7 level is at the end of the high 5v heating phase just before transitioning to the low 1.4v heating voltage. I found mine stabilized in an indoor home environment around 211 after the second heating cycle, corresponding to an analog voltage out of the MQ7 of (211/2013) * 5v = 1.03v. To calibrate I'll need a CO gas meter. Next item on the purchase list :-) Enjoy. Feel free to post below if you build some additional cool stuff on this.

Saturday, February 22, 2014

High Sensitivity Vibration Sensor Using Arduino

In my last post I described how to build a High Sensitivity Arduino Sound Level Detector. Another useful type of sensor to determine if something interesting is going on in the environment is a vibration sensor. In this post I use a piezo element as a raw sensor to detect vibration.

I found the raw piezo generated a very small signal. To greatly improve its sensitivity I used epoxy to glue a fishing weight to the piezo sensor. The piezo drives a load resistor of 1M in parallel with a 5.1v Zener diode just to protect the IC's against any large voltage spikes in the event of a large physical bump. I found the raw output of the piezo unsuitable for direct input to the Arduino as it is typically a very small voltage signal and needs amplification, so I amplify the signal from the piezo with a 221 gain non-inverting op-amp using one side of an LM358. I use the other side of the LM358 for a comparator. The sensitivity of the vibration sensor is controlled using a potentiometer for the threshold (negative) input into the comparator. The other (positive) input to the comparator comes from the amplifier of the piezo signal. The output of the comparator provides a direct input to Arduino Uno digital pin 8. To hear when it senses vibration I use a simple piezo buzzer driven directly from Arduino Uno pin 13. Below is the circuit diagram:

... and the breadboard circuit:

Here is the actual prototype:

... and a close up of the piezo element with the fishing weight glued on with epoxy for added sensitivity:

Here is the sketch I used on the Arduino Uno:

If you want to use this as a starting point you can copy / paste from below:

#define VIBRATION_DIGITAL_IN_PIN 8
#define BUZZER_DIGITAL_OUT_PIN 13

int buzzerDurationMillis = 1000;

void setup(){
  pinMode(VIBRATION_DIGITAL_IN_PIN, INPUT);
  pinMode(BUZZER_DIGITAL_OUT_PIN, OUTPUT);
}

void loop(){
    if(digitalRead(VIBRATION_DIGITAL_IN_PIN) == HIGH){
      digitalWrite(BUZZER_DIGITAL_OUT_PIN, HIGH);
      delay(buzzerDurationMillis);
      digitalWrite(BUZZER_DIGITAL_OUT_PIN, LOW);
    }
}
Enjoy. Let me know if you make any cool improvements on this.

Note: if you notice your output locking in on state try lowering the feedback resistor of the op-amp from 220k to something lower, for example 160k.

Update: I later added a 0.1uF capacitor to connect the output from the piezo element to the input of the op-amp, also grounded on the op-amp side using a 100k resistor. This acted as a DC decoupler and effectively lowered the comparator threshold required to detect vibration.

Monday, February 17, 2014

High Sensitivity Arduino Sound Level Detector

Generally we want to sense the environment when something interesting is occurring. Sometimes the presence of sound is indicative of an interesting activity. If we can detect sound level we can trigger a sensing activity to capture information about the activity of interest. I have posted a short video of this simple high sensitivity Arduino sound level detector working.

In this project we use an Arduino Uno, an electret microphone and an LM358 dual operational amplifier to create a simple sound level detector. The signal from the mic is amplified by the one side of the LM358 with a gain of approximately 221 (see op-amp wiki) as defined by the 220k feedback resistor and the 1k pull down resistor connected to the negative input of the LM258 amplifier. The output of the first stage amplifier provides input to the other side of the LM358 used as a comparator. The triggering threshold of the comparator is controlled using the potentiometer. When the audio signal from the first amp exceeds the triggering threshold the comparator sends a digital '1' to the Arduino Uno on pin 8. When the Uno detects the sound level high input it turns an LED on. You can see a schematic diagram of the sound detection part of the circuit below.

Prototyping this on a breadboard looks something like this:

The actual breadboard prototype appears below:

... and the simple sketch I used to drive the Arduino Uno appears below:

I include the sketch code below if you'd like to try it out yourself:

#define SOUND_DETECTED_DIGITAL_IN_PIN 8
#define LED_DIGITAL_OUT_PIN 7

void setup(){
  pinMode(SOUND_DETECTED_DIGITAL_IN_PIN, INPUT);
  pinMode(LED_DIGITAL_OUT_PIN, OUTPUT);
}

void loop(){
  if(digitalRead(SOUND_DETECTED_DIGITAL_IN_PIN) == HIGH){
    digitalWrite(LED_DIGITAL_OUT_PIN, HIGH);
    delay(50); // delay long enough for you to see the LED on
  }
  else {
    digitalWrite(LED_DIGITAL_OUT_PIN, LOW);
  }
}

Stay tuned for projects that receive the sound detection as input and use it to drive other interesting activities. Have fun. Feel free to share below if you built something cool with this, or have some ideas for enhancements.

Note: if you notice your output locking in on state try lowering the feedback resistor of the op-amp from 220k to something lower, for example 160k.

Friday, November 1, 2013

Is Healthcare Ready for Wearables?

Wearables promise major benefits to healthcare workers in providing new powerful information sources at the point of care, promising hands free operation that enables improved patient care, efficiency and productivity. Research has shown that what users do with technology is a major source of privacy and security risk. While some risk comes from vulnerabilities in the device hardware or software, it is what users do with technology that drives much if not most of the risk. In many cases this is inadvertent, with users unaware of such privacy and security risk side effects. To date, the source of much of this risk is from mobile devices and apps. An example is a healthcare worker using a file transfer app to transfer sensitive personal information such as patient records to a co-worker. While this makes exchange of healthcare information easy and efficient, it subjects such information to risks of breach. It can also compromise the integrity of the master patient record since such transfers and updates often don't update the master patient record, leading to a record that is incomplete or out of date, which in turn can result in suboptimal healthcare, or in a worst case a patient safety issue. Such risks also often have a cloud component, where for example a file transfer involves moving and storing patient information in a cloud, outside the control of the healthcare organization. This side effect is often called BYOC (Bring Your Own Cloud), and aside from confidentiality and integrity risks can also introduce trans border data flow risks. This type of risk is set to increase as users are further empowered with increasingly powerful devices, apps, wearables. Breaches have had major negative impacts on healthcare. Realizing the amazing benefits of these new technologies while minimizing these risks requires a proactive approach in which need to understand the lifecycle and flow of personal information around these devices, anticipate risks, avoid such risks wherever possible, and otherwise make informed and reasonable benefit / risk tradeoffs.

Many wearables are not full stand-alone computing devices in and of themselves, but are closer to advanced IO devices connected wirelessly to a nearby device such as a smartphone. An imminent example of this is Google Glasses. These types of wearables are capable of recording vast quantities of photos, audio and video that exceed the storage and processing capabilities of the local smartphone and therefore will be uploaded to the cloud. Further, this upload to the cloud could be over a personal 4G wireless network that doesn't even touch the healthcare organizations network and so can't be detected or blocked. Envision a patient or caregiver walking into a waiting room, or around a hospital, wearing one of these, recording other patients. While we have precedents of BYOC with mobile devices and apps, wearables such as this are poised to increase this problem drastically. Mitigating this type of risk will be a challenge, and will require a holistic approach consisting of technical safeguards to automatically detect and alert to this type of use and risk, as well as administrative controls such as policy and training, as well as physical controls that prevent the presence and use of such devices in particularly sensitive settings. The initial period after appearance of such wearables is bound to be bumpy, with many unfortunate negative surprises. Ultimately, a new set of social norms must be established that minimize these and streamline the use and benefits of wearables while minimizing risks.

What types of risks are you seeing with wearables in healthcare?