Wiki source for SensorPuck


Show raw source

=====Sensor Puck=====

==a==Waht is the Sensor Puck?==a==

The sensor puck demonstrates Silicon Laboratories optical sensor [[Si1147M01 Si1147-M01]], humidity and temperature sensor [[Si7021]] and Microcontroller ([[EFM32G210]] Gecko). The data is broadcast using a Bluetooth Low Energy (BLE) module.

Data and can be displayed on a mobile device (Apple iOS or Android) that supports the BLE protocol.

Product page:
http://www.silabs.com/products/sensors/Pages/environmental-biometric-sensor-puck.aspx


{{image url="images/SensorPuck.jpg" alt=""}}


==a==Components==a==

- Microcontroller [[EFM32G210]], ARM Cortex-M3
- Switched voltage regulator [[TS3310]]
- Optical sensor [[Si1147M01 Si1147-M01]] (UV index, ambient light, pulse rate)
- Humidity and temperature sensor [[Si7021]]
- Bluetooth Smart Chip [[BCM20732i]], ARM Cortex-M3
- Epson 24 MHz [[http://www.epsondevice.com/docs/qd/en/DownloadServlet?id=ID000658 FA-238 ]]



==a==Receive data on Raspberry Pi==a==

There is an App for iOS and Android, but I would like to see the Sensor Puck data on my living room screen ([[http://homienaut.com/22-zoll-touchscreen-am-homienaut/ Homienaut]]).

This python script helped me a lot to start receiving and converting the data from sensor puck: http://amperture.com/?p=23

Sensor puck sends the data in as advertising packet. This means in terms of Bluetooth Smart there is no connection required. The Sensor Puck is the broadcaster and the [[http://homienaut.com/22-zoll-touchscreen-am-homienaut/ Homienaut]] is the observer.
I found this broadcast format specification very useful to determinate additional parameters of the sensor (ambient light, UV index, battery voltage and pulse rate).
http://community.silabs.com/mgrfq63796/attachments/mgrfq63796/6/10653/1/Silicon%20Labs%20Sensor%20Puck%20App.pdf

I wrote two applications: a command line application and a GUI application in python.


==a==Terminal Application==a==

I wrote this code based on the implementation from http://amperture.com/?p=23

The Sensor Puck has two modes. Usually Sensor Puck is in enviromental mode. If you put a finger on the optical sensor, the puck switches into biometric.

My script delivers the following parameters.

== Enviromental Mode ==

Humidity: 51.4 %
Temperature: 20.5 C
Ambient light: 1.5 Lux
UV index: 0.0
Battery voltage: 3.0 V


== Biometric Mode ==

HRM state: Active
Pulse rate: 72 bpm




%%(python)
# Code based on the implementation from http://amperture.com/?p=23
# With additions by Andreas Tobola, October 2015, http://tnotes.de/SensorPuck

import subprocess
import os

proc = subprocess.Popen(['hcidump --raw'], stdout=subprocess.PIPE, shell=True)

hrmStateStr = ['Idle', 'No Signal', 'Acquiring', 'Active', 'Invalid', 'Error']

while True:
line = proc.stdout.readline()
if ">" not in line:
hexarray = line.split()
N = len(hexarray)

os.system('clear')

if N==14:
print "== Enviromental Mode ==\n"

# Humidity uint16 deciprecent
humidity = (int(hexarray[6], 16) << 8) + int(hexarray[5], 16)
humidity = float(humidity)/10

# Temperature int16 decidegrees (can be negative -> twos complement)
temp = (int(hexarray[8], 16) << 8) + int(hexarray[7], 16)
temp = float(temp)/10

# Ambient Light uint16 lux/2
amblight = (int(hexarray[10], 16) << 8) + int(hexarray[9], 16)
amblight = float(amblight)/2

# UV Index uint8 index
uvidx = int(hexarray[11], 16)

# Battery Voltage uint8 decivolts
vbat = int(hexarray[12], 16)
vbat = float(vbat)/10

print u"Humidity: %.1f " %humidity + '%'
print u"Temperature: %.1f \xb0C" %temp
print "Ambient light: %.1f Lux" %amblight
print "UV index: %.1f" %uvidx
print "Battery voltage: %.1f V" %vbat
elif N==18:
print "== Biometric Mode ==\n"

# HRM State uint8 none
hrmState = int(hexarray[5], 16)
print "HRM state: " + hrmStateStr[hrmState]

# HRM Rate uint8 bpm
pulseRate = int(hexarray[6], 16)
print "Pulse rate: " + str(pulseRate) + " bpm"

# HRM Sample Array uint16[5] none
# ...
print " "
%%


The Sensor Puck has two modes Enviromental and Biometric Mode.

If the finger is on the optical sensor, the sensor switches into Biometric Mode.

Depending on the mode the sensor broadcasts different data.





==a==GUI Application==a==

Additionally, I wrote a python script with GUI based using [[Tkinter]] to visualize the data.


{{image url="images/SensorPuck1.jpg" alt=""}}

{{image url="images/SensorPuck2.jpg" alt=""}}

{{image url="images/SensorPuck4.jpg" alt=""}}


Put your finger on the optical sensor of the Sensor Puck to measure the pulse rate.

{{image url="images/SensorPuck6.jpg" alt=""}}



%%(python)
#!/usr/bin/python
# Thos is a GUI version of the Sensor Puck Script at http://tnotes.de/SensorPuck
# Andreas Tobola, October 2015
# Version 1.4

from Tkinter import *
import time
import thread
import subprocess
import os

# XML-RPC to provide the sensor data for other processes
from SimpleXMLRPCServer import SimpleXMLRPCServer
from SimpleXMLRPCServer import SimpleXMLRPCRequestHandler



bgcolor = 'black';
fgcolor = 'light blue'
fgcolorerr = 'Orange Red'

#bgcolor = '#A0A0F8';
#fgcolor = '#302040'
#fgcolorerr = '#801020'


temp = 0.0
amblight = -1.0

def getTemperature():
return temp

def getAmbLight():
return amblight

def threadSensorDecoder():
global tTimeOutObserver
global temp
global amblight
while 1:
line = proc.stdout.readline()

if ">" not in line:
hexarray = line.split()
N = len(hexarray)

tTimeOutObserver = time.time() + 42

if N==14:

# Humidity uint16 deciprecent
humidity = (int(hexarray[6], 16) << 8) + int(hexarray[5], 16)
humidity = float(humidity)/10

# Temperature int16 decidegrees (can be negative -> twos complement)
temp = (int(hexarray[8], 16) << 8) + int(hexarray[7], 16)
temp = float(temp)/10

# Ambient Light uint16 lux/2
amblight = (int(hexarray[10], 16) << 8) + int(hexarray[9], 16)
amblight = float(amblight)/2

# UV Index uint8 index
uvidx = int(hexarray[11], 16)

# Battery Voltage uint8 decivolts
vbat = int(hexarray[12], 16)
vbat = float(vbat)/10

laSensData['text'] = u'Temperature: %.1f \xb0C \n Humidity: %.1f ' %(temp, humidity) + '%' + ' \n Ambient light: %.1f Lux \n UV index: %d \n Battery voltage: %.1f V' %(amblight, uvidx, vbat)

txtExtra = '';
if humidity > 58.0:
txtExtra += 'Ventilate the room.\n'
if temp > 25.0:
txtExtra += 'It\'s incredible hot in here!\n'
elif temp > 22.5:
txtExtra += 'It\'s hot in here.\n'
elif temp < 18.0:
txtExtra += 'It\'s cold in here!\n'
if vbat < 2.7:
txtExtra += 'Low sensor battery.\n'

laExtra['text'] = txtExtra;


elif N==18:

# HRM State uint8 none
hrmState = int(hexarray[5], 16)

# HRM Rate uint8 bpm
pulseRate = int(hexarray[6], 16)

# HRM Sample Array uint16[5] none
# maybe one day...

laSensData['text'] = u'Pulse Sensor Mode \n Sensor state: %s \n Pulse rate: %d bpm' %(hrmStateStr[hrmState], pulseRate)

txtExtra = '';
if hrmState == 3:
if pulseRate > 120:
txtExtra += 'Your pulse rate is high.\n'
if pulseRate < 50:
txtExtra += 'Your pulse rate is low.\n'
laExtra['text'] = txtExtra;




def threadSensorObserver():

global temp
while 1:
time.sleep(2)
if time.time() > tTimeOutObserver:
laSensData['text'] = '';
laExtra['text'] = 'Sensor out of range.';
temp = 0;



def threadSensorDataServer():

# Restrict to a particular path.
class RequestHandler(SimpleXMLRPCRequestHandler):
rpc_paths = ('/RPC2',)

# Create server
server = SimpleXMLRPCServer(("localhost", 8201), requestHandler=RequestHandler)
server.register_function(getTemperature, 'getTemperature')
server.register_function(getAmbLight, 'getAmbLight')



server.serve_forever() # Run the server's main loop




tTimeOutObserver = time.time() + 12

master = Tk()

master.configure(background=bgcolor)
fontSensData = ("Helvetica",30,"bold");

w = Label(master, text="Sensor Puck", font = ("Helvetica",50,"bold"), bg=bgcolor, fg=fgcolor )
w.pack()

laSensData = Label(master, text="...", font = fontSensData, bg=bgcolor, fg=fgcolor )
laSensData.pack()

laExtra = Label(master, text="", font = fontSensData, bg=bgcolor, fg=fgcolorerr )
laExtra.pack()

proc = subprocess.Popen(['sudo hcidump --raw'], stdout=subprocess.PIPE, shell=True)

hrmStateStr = ['Idle', 'No Signal', 'Acquiring', 'Active', 'Invalid', 'Error']


try:
thread.start_new_thread( threadSensorObserver, () )
thread.start_new_thread( threadSensorDecoder, () )
thread.start_new_thread( threadSensorDataServer, () )
except:
print "Error: unable to start thread"




mainloop()
%%

Just in case you ask yourself the question, why I didn't used the escape char ""%%"" in my formated string constructions. Well, ""%%"" is the escape char for end of code in my Wiki. So I use + '%' + instead to be able to post this code here. But both solution deliver an equal result.


==a==Sensor Puck Firmware Modifications==a==

Change advertising period from 500 ms
%%(c;;ble.c)
BLE_SetAdvertisingParameters(800, 0, 800, 0);
%%
to 10 seconds advertising periods (only in envirometal mode).
%%(c;;ble.c)
BLE_SetAdvertisingParameters(16000, 0, 16000, 0);
%%

Change sensor data update function from 1 second
%%(c;;sensor_puck.h)
#define PERIODIC_UPDATE_MS 1000
%%
to 10 seconds.
%%(c;;sensor_puck.h)
#define PERIODIC_UPDATE_MS 10000
%%

Average current reduction from ~225 µA to ~70 µA @ 3 V in environmental mode.




----
Siehe auch {{backlinks}}
Valid XHTML :: Valid CSS: :: Powered by WikkaWiki