【W(wǎng)SN】基于XBea連續(xù)監(jiān)測(cè)無線溫度傳感器網(wǎng)絡(luò)附matlab代碼
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智能優(yōu)化算法?? ? ??神經(jīng)網(wǎng)絡(luò)預(yù)測(cè)?? ? ??雷達(dá)通信?? ? ?無線傳感器?? ? ? ?電力系統(tǒng)
信號(hào)處理?? ? ? ? ? ? ?圖像處理?? ? ? ? ? ? ??路徑規(guī)劃?? ? ??元胞自動(dòng)機(jī)?? ? ? ?無人機(jī)
?? 內(nèi)容介紹
摘要:無線傳感器網(wǎng)絡(luò)(WSN)已經(jīng)成為了現(xiàn)代科技領(lǐng)域中的熱門話題。在許多應(yīng)用領(lǐng)域,如環(huán)境監(jiān)測(cè)、農(nóng)業(yè)、醫(yī)療保健和工業(yè)自動(dòng)化中,WSN都被廣泛應(yīng)用。其中,溫度傳感器網(wǎng)絡(luò)在許多實(shí)時(shí)監(jiān)測(cè)和控制應(yīng)用中起著重要作用。本文將介紹一種基于XBea的連續(xù)監(jiān)測(cè)無線溫度傳感器網(wǎng)絡(luò)算法步驟。
引言:隨著科技的不斷發(fā)展,無線傳感器網(wǎng)絡(luò)的應(yīng)用范圍越來越廣泛。無線傳感器網(wǎng)絡(luò)由許多小型傳感器節(jié)點(diǎn)組成,這些節(jié)點(diǎn)可以通過無線通信進(jìn)行數(shù)據(jù)傳輸和交互。溫度傳感器網(wǎng)絡(luò)是無線傳感器網(wǎng)絡(luò)中的一種重要類型,可以用于監(jiān)測(cè)和控制環(huán)境中的溫度變化。
XBea是一種常用的無線通信模塊,可以用于構(gòu)建無線傳感器網(wǎng)絡(luò)。它具有低功耗、低成本和易于使用的特點(diǎn),非常適合于溫度傳感器網(wǎng)絡(luò)的應(yīng)用。本文將基于XBea模塊,介紹一種連續(xù)監(jiān)測(cè)無線溫度傳感器網(wǎng)絡(luò)的算法步驟。
算法步驟:
部署傳感器節(jié)點(diǎn):首先,需要在監(jiān)測(cè)區(qū)域內(nèi)部署一定數(shù)量的傳感器節(jié)點(diǎn)。這些傳感器節(jié)點(diǎn)應(yīng)該均勻分布在整個(gè)區(qū)域內(nèi),以確保溫度監(jiān)測(cè)的全面性和準(zhǔn)確性。
建立通信網(wǎng)絡(luò):使用XBea模塊建立傳感器節(jié)點(diǎn)之間的通信網(wǎng)絡(luò)。每個(gè)傳感器節(jié)點(diǎn)都與周圍的節(jié)點(diǎn)建立連接,形成一個(gè)無線傳感器網(wǎng)絡(luò)。通過這個(gè)網(wǎng)絡(luò),節(jié)點(diǎn)可以相互傳輸溫度數(shù)據(jù)和控制命令。
數(shù)據(jù)采集和傳輸:每個(gè)傳感器節(jié)點(diǎn)定期采集周圍環(huán)境的溫度數(shù)據(jù),并將數(shù)據(jù)通過XBea模塊傳輸給相鄰的節(jié)點(diǎn)。通過這種方式,溫度數(shù)據(jù)可以在整個(gè)網(wǎng)絡(luò)中傳輸和共享。
數(shù)據(jù)處理和分析:接收到溫度數(shù)據(jù)的節(jié)點(diǎn)將對(duì)數(shù)據(jù)進(jìn)行處理和分析。節(jié)點(diǎn)可以根據(jù)預(yù)先設(shè)定的閾值進(jìn)行溫度異常檢測(cè),并采取相應(yīng)的控制措施。同時(shí),節(jié)點(diǎn)還可以將處理后的數(shù)據(jù)傳輸給基站或上級(jí)節(jié)點(diǎn),以供進(jìn)一步的分析和決策。
能量管理:為了延長(zhǎng)網(wǎng)絡(luò)的壽命,需要對(duì)能量進(jìn)行有效的管理。節(jié)點(diǎn)可以根據(jù)能量消耗情況進(jìn)行自適應(yīng)的工作調(diào)度,以減少能量消耗并延長(zhǎng)節(jié)點(diǎn)的使用壽命。此外,還可以采用能量回收和能量傳輸?shù)燃夹g(shù),以提供節(jié)點(diǎn)的能量供應(yīng)。
結(jié)論:本文介紹了一種基于XBea的連續(xù)監(jiān)測(cè)無線溫度傳感器網(wǎng)絡(luò)的算法步驟。通過部署傳感器節(jié)點(diǎn)、建立通信網(wǎng)絡(luò)、數(shù)據(jù)采集和傳輸、數(shù)據(jù)處理和分析以及能量管理等步驟,可以實(shí)現(xiàn)對(duì)溫度的連續(xù)監(jiān)測(cè)和控制。這種算法步驟可以為溫度傳感器網(wǎng)絡(luò)的設(shè)計(jì)和應(yīng)用提供一種有效的解決方案,具有重要的實(shí)際意義和應(yīng)用前景。
?? 部分代碼
%% Introduction
% In <part1_buildingthenetwork.html part one>, <part2_gatheringdata.html
% part two>, and <part3_calibration.html part three> of this series of blog
% post I went through the process of reading voltages from a network of
% XBee(R) modules, building and testing my wireless network of temperature
% sensors, calibrating the sensors, and gathering temperature data from the
% network of sensors in my apartment. In this post I will show you some of
% the basic analyses I performed on the data. In particular, I have two
% goals:
%
% # determine how long it takes for my apartment to warm up after
% the heat has been turned on, and
% # find out what rooms in my apartment
% take the longest to heat up, so I can make the necessary adjustments to
% my radiators so that all the rooms warm up at the same rate.
%% Overview of Data
% As I mentioned in a previous post, I collected the temperature every two
% minutes over the course of 9 days. I placed 14 sensors in my apartment: 9
% located inside, 2 located outside, and 3 located in radiators. The data
% is stored in the file <../twoweekstemplog.txt |twoweekstemplog.txt|>.
[tempF,ts,location,lineSpecs] = XBeeReadLog('twoweekstemplog.txt',60);
tempF = calibrateTemperatures(tempF);
plotTemps(ts,tempF,location,lineSpecs)
legend('off')
xlabel('Date')
title('All Data Overview')
%%
% _Figure 1: All temperature data from a 9 day period._
%
% That graph is a bit too cluttered to be very meaningful. Let me remove
% the radiator data and the legend and see if that helps.
notradiator = [1 2 3 5 6 7 8 9 10 12 13];
plotTemps(ts,tempF(:,notradiator),location(notradiator),lineSpecs(notradiator,:))
legend('off')
xlabel('Date')
title('All Inside and Outside Temperature Data')
%%
% _Figure 2: Just inside and outside temperature data, with radiator data removed._
%
% Now I can see some places where one of the outdoor temperature sensors
% (blue line) gave erroneous data, so let's remove those data points. This
% data was collected in March in Massachusetts, so I can safely assume the
% outdoor temperature never reached 80 F. I replaced any values above 80 F
% with |NaN| (not-a-number) so they are ignored in further analysis.
outside = [3 10];
outsideTemps = tempF(:,outside);
toohot = outsideTemps>80;
outsideTemps(toohot) = NaN;
tempF(:,outside) = outsideTemps;
plotTemps(ts,tempF(:,notradiator),location(notradiator),lineSpecs(notradiator,:))
legend('off')
xlabel('Date')
title('Cleaned-up Inside and Outside Temperature Data')
%%
% _Figure 3: Inside and outside temperature data with erroneous data removed._
%
% I'll also remove all but one inside sensor per room, and give the
% remaining sensors shorter names, to keep the graph from getting too
% cluttered.
show = [1 5 9 12 10 3];
location(show) = ...
? ?{'Bedroom','Kitchen','Living Room','Office','Front Porch','Side Yard'}';
plotTemps(ts,tempF(:,show),location(show),lineSpecs(show,:))
ylim([0 90])
legend('Location','SouthEast')
xlabel('Date')
title('Summary of Temperature Data')
%%
% _Figure 4: Summary of temperature data with only one inside temperature
% sensor per room with outside temperatures._
%
% That looks much better. This data was collected over the course of 9
% days, and the first thing that stands out to me is the periodic outdoor
% temperature, which peaks every day at around noon. I also notice a sharp
% spike in the side yard (green) temperature on most days. My front porch
% (blue) is located on the north side of my apartment, and does not get
% much sun. My side yard is on the east side of my apartment, and that
% spike probably corresponds to when the sun hits the sensor from between
% my apartment and the building next door.
%% When do my radiators start to heat up?
% The radiator temperature can be used to measure how long it takes for my
% boiler and radiators to warm up after the heat has been turned on. Let's
% take a look at 1 day of data from the living room radiator:
% Grab the Living Room Radiator Temperature (index 11) from the |tempF| matrix.
radiatorTemp = tempF(:,11);
% Fill in any missing values:
validts = ts(~isnan(radiatorTemp));
validtemp = radiatorTemp(~isnan(radiatorTemp));
nants = ts(isnan(radiatorTemp));
radiatorTemp(isnan(radiatorTemp)) = interp1(validts,validtemp,nants);
% Plot the data
oneday = [ts(1) ts(1)+1];
figure
plot(ts,radiatorTemp,'k.-')
xlim(oneday)
xlabel('Time')
ylabel('Radiator Temperature (\circF)')
title('Living Room Radiator Temperature')
datetick('keeplimits')
snapnow
%%
% _Figure 5: One day of temperature data from the living room radiator._
%
% As expected, I see a sharp rise in the radiator temperature, followed by
% a short leveling off (when the radiator temperature maxes out the
% temperature sensor), and finally a gradual cooling of the radiator. Let
% me superimpose the rate of change in temperature onto the plot.
tempChange = diff([NaN; radiatorTemp]);
hold on
plot(ts,tempChange,'b.-')
legend({'Temperature', 'Temperature Change'},'Location','Best')
%%
% _Figure 6: One day of data from the living room radiator with temperature change._
%
% It looks like I can detect those peaks by looking for large jumps in the
% temperature. After some trial and error, I settled on three criteria to
% identify when the heat comes on:
%
% # Change in temperature greater than four times the previous change in temperature.
% # Change in temperature of more than 1 degree F.
% # Keep the first in a sequence of matching points (remove doubles)
fourtimes = [tempChange(2:end)>abs(4*tempChange(1:end-1)); false];
greaterthanone = [tempChange(2:end)>1; false];
heaton = fourtimes & greaterthanone;
doubles = [false; heaton(2:end) & heaton(1:end-1)];
heaton(doubles) = false;
%%
% Let's see how well I detected those peaks by superimposing red dots over
% the times I detected.
figure
plot(ts,radiatorTemp,'k.-')
hold on
plot(ts(heaton),radiatorTemp(heaton),'r.','MarkerSize',20)
xlim(oneday);
datetick('keeplimits')
xlabel('Time')
ylabel('Radiator Temperature (\circF)')
title('Heat On Event Detection')
legend({'Temperature', 'Heat On Event'},'Location','Best')
%%
% _Figure 7: Radiator temperature with heating events marked with red dots._
%
% Looks pretty good, which means now I have a list of all the times that
% the heat came on in my apartment.
heatontimes = ts(heaton);
%% How long does it take for my heat to turn on?
% I currently have a programmable 5/2 thermostat, which means I can set
% one program for weekdays (Monday through Friday) and one program for both
% Saturday and Sunday. I know my thermostat is set to go down to 62 at
% night, and back up to 68 at 6:15am Monday through Friday and 10:00am on
% Saturday and Sunday. I used that knowledge to determine how long after my
% thermostat activates that my radiators warm up.
%
% I started by creating a vector of all the days in the test period. I
% removed Monday because I manually turned on the thermostat early that day.
mornings = floor(min(ts)):floor(max(ts));
mornings(2) = []; % Remove Monday
%%
% Then I added either 6:15am or 10:00am to each day depending on whether it
% was a weekday or a weekend.
isweekend = weekday(mornings) == 1 | weekday(mornings) == 7;
mornings(isweekend) = mornings(isweekend)+10/24; % 10:00 AM
mornings(~isweekend) = mornings(~isweekend)+6.25/24; % 6:15 AM
%%
% Next I looked for the first time the heat came on after the programmed
% time each morning.
heatontimes_mat = repmat(heatontimes,1,length(mornings));
mornings_mat = repmat(mornings,length(heatontimes),1);
timelag = heatontimes_mat - mornings_mat;
timelag(timelag<=0) = NaN;
[delay, heatind] = min(timelag);
delay = round(delay*24*60);
%%
% Let's take a look at those times to make sure we found the right ones.
% In this plot, I'll circle in blue the first time the heat comes on each
% morning, and plot blue vertical lines indicating when the thermostat
% turns on each morning.
heatontemp = radiatorTemp(heaton);
onemorning = mornings(3)+[-1/24 5/24];
figure
plot(ts,radiatorTemp,'k.-')
hold on
plot(heatontimes,heatontemp,'r.','MarkerSize',20)
plot(heatontimes(heatind),heatontemp(heatind),'bo','MarkerSize',10)
plot([mornings;mornings],repmat(ylim',1,length(mornings)),'b-');
xlim(onemorning);
datetick('keeplimits')
xlabel('Time')
ylabel('Radiator Temperature (\circF)')
title('Detection of Scheduled Heat On Events')
legend({'Temperature', 'Heat On Event', 'Scheduled Heat On Event',...
? ?'Scheduled Event'},'Location','Best')
%%
% _Figure 8: Six hours of radiator data, with a blue line indicating when
% the thermostat turned on in the morning, and blue circle indicating the
% corresponding heat on event of the radiator._
%
% Let's look at a histogram of those delays:
figure
hist(delay,min(delay):max(delay))
xlabel('Minutes')
ylabel('Frequency')
title('How long before the radiator starts to warm up?')
%%
% _Figure 9: Histogram showing delay between thermostat activation and the
% radiators starting to warm up._
%
% It looks like the delay between the thermostat coming on in the morning
% and the radiators starting to warming up can range from 7 minutes to as
% high as 24 minutes, but on average this delay is around 12-13 minutes.
heatondelay = 12;
%% How long does it take for the radiators to warm up?
% Once the radiators start to warm up, it takes a few minutes for them to
% reach full temperature. Let's look at how long this takes. I'll look for
% times when the radiator temperature first maxes out the temperature
% sensor after having been below the maximum for at least 10 minutes (5
% samples).
maxtemp = max(radiatorTemp);
radiatorhot = radiatorTemp(6:end)==maxtemp & ...
? ?radiatorTemp(1:end-5)<maxtemp &...
? ?radiatorTemp(2:end-4)<maxtemp &...
? ?radiatorTemp(3:end-3)<maxtemp &...
? ?radiatorTemp(4:end-2)<maxtemp &...
? ?radiatorTemp(5:end-1)<maxtemp;
radiatorhot = [false(5,1); radiatorhot];
radiatorhottimes = ts(radiatorhot);
%%
% Let's see how well that worked:
figure
plot(ts,radiatorTemp,'k.-')
hold on
plot(ts(heaton),radiatorTemp(heaton),'r.','MarkerSize',20)
plot(ts(radiatorhot),radiatorTemp(radiatorhot),'b.','MarkerSize',20)
xlim(onemorning);
datetick('keeplimits')
xlabel('Time')
ylabel('Radiator Temperature (\circF)')
title('Radiator Hot Event Detection')
legend({'Temperature', 'Heat On Event', 'Radiator Hot Event'},...
? ?'Location','Best')
%%
% _Figure 10: Six hours of radiator data, with red dots indicating the heat
% coming on and blue dots indicating the radiator is hot._
%
% Now I'll match the |radiatorhottimes| to the |heatontimes| using the same
% technique I used above.
radiatorhottimes_mat = repmat(radiatorhottimes',length(heatontimes),1);
heatontimes_mat = repmat(heatontimes,1,length(radiatorhottimes));
timelag = radiatorhottimes_mat - heatontimes_mat;
timelag(timelag<=0) = NaN;
[delay, foundmatch] = min(timelag);
delay = round(delay*24*60);
%%
% Let's look at a histogram of those delays:
figure
hist(delay,min(delay):2:max(delay))
xlabel('Minutes');
ylabel('Frequency')
title('How long does the radiator take to warm up?')
%%
% _Figure 11: Histogram showing time required for the radiators to warm up._
%
% It looks like the radiators take between 4 and 8 minutes from when they
% start to warm up until they are at full temperature.
radiatorheatdelay = 6;
%%
% Later on in my analysis, I will only want to use times that the heat came
% on and the radiators reached full temperature, so I will only keep those
% values in the |heaton| vector.
heatonind = find(heaton);
heatonind = heatonind(foundmatch);
heaton = false(size(heaton));
heaton(heatonind) = true;
%% When do the radiators cool off?
% I'll use the same technique as above to detect when the radiators start
% to cool off, which must mean the heat has gone off.
heatoff = radiatorTemp(1:end-5)==maxtemp & ...
? ?radiatorTemp(2:end-4)<maxtemp &...
? ?radiatorTemp(3:end-3)<maxtemp &...
? ?radiatorTemp(4:end-2)<maxtemp &...
? ?radiatorTemp(5:end-1)<maxtemp &...
? ?radiatorTemp(6:end)<maxtemp;
heatoff = [heatoff; false(5,1)];
heatofftimes = ts(heatoff);
heatoffind = find(heatoff);
%%
% Let's take a look at the heat on, radiator hot, and heat off times all
% together in one graph.
figure
plot(ts,radiatorTemp,'k.-')
hold on
plot(ts(heaton),radiatorTemp(heaton),'r.','MarkerSize',20)
plot(ts(radiatorhot),radiatorTemp(radiatorhot),'b.','MarkerSize',20)
plot(ts(heatoff),radiatorTemp(heatoff),'g.','MarkerSize',20)
xlim(onemorning);
datetick('keeplimits')
xlabel('Time')
ylabel('Radiator Temperature (\circF)')
title('Radiator Cooling Event Detection')
legend({'Temperature', 'Heat On Event', 'Radiator Hot Event',...
? ?'Radiator Cooling Event'},'Location','Best')
%%
% _Figure 12: Six hours of radiator data, with red dots indicating the heat
% coming on, blue dots indicating the radiator is hot, and green dots
% indicating the radiator starting to cool._
%
%% How long does it take my living room to warm up?
% Now that I know it takes about 12-13 minutes from the time my thermostat
% activates in the morning until the radiators start to warm up, and
% another 4-8 minutes for the radiators themselves to warm up, let's look
% at how long it actually takes my apartment to warm up after the radiators
% heat up. I'll focus on the living room inside temperature for now.
%%
% Grab the Living Room Inside Temperature (index 9) from the |tempF| matrix.
livingroomtemp = tempF(:,9);
%%
% Let's look at one day's worth of living room inside temperatures to see
% how they compare the the living room radiator temperatures.
figure
[ax,p1,p2] = plotyy(ts,radiatorTemp,ts,livingroomtemp);
set(ax,'XLim',oneday)
set(ax(1),'YColor','k','YLim',[60 180],'YTick',60:20:180)
set(ax(2),'YColor','b','YLim',[60 ?72],'YTick',60:2:72,'XTick',[])
set(p1,'Color','k')
set(p2,'Color','b')
datetick(ax(1),'keeplimits')
xlabel(ax(1),'Time')
ylabel(ax(1),'Radiator Temperature (\circF)')
ylabel(ax(2),'Room Temperature (\circF)')
title('Living Room and Radiator Temperatures')
legend([p1,p2],{'Radiator Temperature','Room Temperature'},'Location','SouthEast')
%%
% _Figure 13: Living room and radiator temperatures plotted overlapping but
% with different y-axes scaling._
%
% As you would expect, once the radiator temperatures rise, so do the room
% temperatures, but I would like to find out how quickly the room
% temperatures rise. To do that, I will first break up the temperature data
% into segments delimited by the times the heat came on. I'll keep only the
% rising portion of each segment (up to the first occurrence of the maximum
% temperature in the segment, or until the heat is off). I'll also keep
% track of the minimum and maximum temperature in the segment, and at what
% time those temperatures occur. I am initializing a matrix to store the
% segments (|segmentTemps|) so that segments that are shorter than the
% maximum length are padded with |NaN| values instead of zeros.
numSegments = sum(heaton);
segmentSizes = heatoffind-heatonind+1;
segmentTemps = NaN(numSegments, max(segmentSizes));
for c = 1:numSegments
? ?segmentTemps(c,1:segmentSizes(c)) = livingroomtemp(heatonind(c):heatoffind(c));
? ?[segmentMaxTemp(c,1),segmentTimeToMax(c,1)] = max(segmentTemps(c,:));
? ?[segmentMinTemp(c,1),segmentTimeToMin(c,1)] = min(segmentTemps(c,1:segmentTimeToMax(c)));
? ?segmentTemps(c,segmentTimeToMax(c)+1:end) = NaN;
end
% Clip off columns that are all NaN at the end of the matrix.
maxSegmentSize = max(segmentTimeToMax);
segmentTemps = segmentTemps(:,1:maxSegmentSize);
% Shift from 1-based indexes to 0-based minutes.
segmentTimeToMin = (segmentTimeToMin - 1)*2;
segmentTimeToMax = (segmentTimeToMax - 1)*2;
segmentTimes = (0:(maxSegmentSize-1))*2; % Time since heat came on in minutes
%%
% Let's take a look at one of these segments:
figure
plot(segmentTimes, segmentTemps(1,:),'b.-')
hold on
plot(segmentTimeToMin(1),segmentMinTemp(1),'r.','MarkerSize',20)
legend({'Temperature','Minimum Temperature'},'Location','NorthWest')
xlabel('Minutes since radiator started to warm')
ylabel('Temperature (\circF)')
title('Room Temperature During One Heating Event')
%%
% _Figure 14: Room temperature during one heating event, time zero is when
% the radiator started to warm up._
%
% In the plot you can see that the temperature continues to decrease for a
% few minutes, then seems to rise almost linearly. Based on this
% information, let's shift the plot so that the base of the linear increase
% in temperature is at the origin.
figure
plot(segmentTimes-segmentTimeToMin(1), segmentTemps(1,:)-segmentMinTemp(1),'b.-')
legend({'Temperature Increase'},'Location','NorthWest')
xlabel('Minutes since minimum temperature')
ylabel('Temperature Increase (\circF)')
title('Shifted Room Temperature During One Heating Event')
%%
% _Figure 15: Change in room temperature during one heating event, time
% zero is when the room temperature reached its minimum value._
%
% That was just one segment, let's look at all of them, with the data
% shifted so that the lowest temperature in each segment occurs at the
% origin.
%%
% First I shift all the times based on the |segmentTimeToMin|
segmentTimes_mat = repmat(segmentTimes,length(segmentTimeToMin),1);
segmentTimeToMin_mat = repmat(segmentTimeToMin,1,length(segmentTimes));
segmentTimesShifted = segmentTimes_mat - segmentTimeToMin_mat;
%%
% Then shift all the temperatures based on the |segmentMinTemp|
segmentMinTemp_mat = repmat(segmentMinTemp,1,size(segmentTemps,2));
segmentTempsShifted = segmentTemps - segmentMinTemp_mat;
%%
% And find the total temperature change and time for each segment.
segmentRiseTime = segmentTimeToMax-segmentTimeToMin;
segmentTempRise = segmentMaxTemp-segmentMinTemp;
%%
% Now I can plot the shifted data
figure
h1 = plot(segmentTimesShifted',segmentTempsShifted','b-');
legend(h1(1),{'Temperature Increase'},'Location','NorthWest')
xlim([-10 max(segmentTimesShifted(:))])
xlabel('Minutes since minimum temperature')
ylabel('Temperature Increase (\circF)')
title('Shifted Room Temperature During All Heating Events')
%%
% _Figure 16: Change in room temperature during all heating events, time
% zero is when the room temperature reached its minimum value._
%
% Although it isn't perfect, it looks close to a linear relationship. Since
% I am interested in the time it takes to reach the desired temperature
% (what could be considered the "specific heat capacity" of the room), let
% me replot the data with time on the y-axis and temperature on the x-axis
% (swapping the axes from the previous figure). I'll also plot the data as
% individual points instead of lines, because that is how the data is going
% to be fed into |polyfit| later.
% Remove temperatures occuring before the minimum temperature.
segmentTempsShifted(segmentTimesShifted<0) = NaN;
figure
h1 = plot(segmentTempsShifted',segmentTimesShifted','k.');
xlabel('Temperature Increase (\circF)')
ylabel('Minutes since minimum temperature')
title('Time to Heat Living Room')
snapnow
%%
% _Figure 17: The time it takes to heat the living room (axes flipped from
% Figure 16)._
%
% Now let me fit a line to the data so I can get an equation for the time
% it takes to heat the living room.
%%
% First I collect all the time and temperature data into a single column
% vector and remove |NaN| values.
allTimes = segmentTimesShifted(:);
allTemps = segmentTempsShifted(:);
allTimes(isnan(allTemps)) = [];
allTemps(isnan(allTemps)) = [];
%%
% Then I can fit a line to the data.
linfit = polyfit(allTemps,allTimes,1);
%%
% Let's see how well we fit the data.
hold on
h2 = plot(xlim,polyval(linfit,xlim),'r-');
linfitstr = sprintf('Linear Fit (y = %.1f*x + %.1f)',linfit(1),linfit(2));
legend([ h1(1), h2(1) ],{'Data',linfitstr},'Location','NorthWest')
%%
% _Figure 18: The time it takes to heat the living room along with a linear fit to the data._
%
% Not a bad fit. Looking closer at the coefficients from the linear fit, it
% looks like it takes about 3 minutes after the radiators start to heat up
% for the room to start to warm up. After that, it takes about 5 minutes
% for each degree of temperature increase.
%% What room takes the longest to warm up?
% I can apply the techniques above to each room to find out how long each
% room takes to warm up. I took the code above and put it into a separate
% function called <../temperatureAnalysis.m |temperatureAnalysis|>, and
% applied that to each inside temperature sensor.
inside = [1 5 9 12];
figure
xl = [0 14];
for s = 1:size(inside,2)
? ?linfits(s,1:2) = temperatureAnalysis(tempF(:,inside(s)), heaton, heatoff);
? ?y = polyval(linfits(s,1:2),xl) + heatondelay;
? ?plot(xl, y, lineSpecs{inside(s),1}, 'Color',lineSpecs{inside(s),2},...
? ? ? ?'DisplayName',location{inside(s)})
? ?hold on
end
legend('Location','NorthWest')
xlabel('Desired temperature increase (\circF)')
ylabel('Estimated minutes to heat')
title('Estimated Time to Heat Each Room')
%%
% _Figure 19: The estimated time it takes to heat each room in my apartment._
%
%%
% In <part1_buildingthenetwork.html part one> of this series of blog posts,
% I mentioned that "I often find that even though the thermostat shows a
% nice and toasty 73, I'm sitting in my bedroom or the office freezing."
% Given that my thermostat is located in the living room, the data backs up
% my anecdotal observation: the office and bedroom take almost twice as
% long to warm up as the living room, while the kitchen warms up a little
% faster than the living room.
%% Conclusions
% I started this series of blog posts with the intention of using a
% wireless network of temperature sensors (built using XBee(R) modules) to
% get a better understanding of how long my heating system takes to warm up
% my apartment, and to use that knowledge to help tune my heating system to
% provide more uniform heating.
%
% The analysis above is just the start of the analysis that can be done on
% this data, but it is enough to help me to tune my heating system. I'll
% start by opening the valves on the bedroom and office radiators more, and
% maybe even close the valves on the living room and kitchen radiators a
% little. Then I'll collect data for another week and see whether that
% helps.
%
% I now also know that my heating system takes around 15-20 minutes from
% when the heat comes on until the temperature starts to rise, and at best
% it takes about 3-5 minutes for each degree of temperature increase. My
% thermostat is set to allow the temperature to drop to 62 degrees at
% night, and warm up to 68 in the morning. Looking up 6 degrees on that
% last plot, I should adjust my thermostat to come on at least 30-40
% minutes before I get up in the morning so it has enough time to warm up.
% No wonder my heating bill is so high.
?? 運(yùn)行結(jié)果







?? 參考文獻(xiàn)
[1] 肖三強(qiáng),羅文廣.基于無線傳感器網(wǎng)絡(luò)的智能溫度測(cè)量系統(tǒng)的設(shè)計(jì)[J].裝備制造技術(shù), 2014(7):3.DOI:10.3969/j.issn.1672-545X.2014.07.039.
[2] 王翥,郝曉強(qiáng),魏德寶.基于WSN和GPRS網(wǎng)絡(luò)的遠(yuǎn)程水質(zhì)監(jiān)測(cè)系統(tǒng)[J].儀表技術(shù)與傳感器, 2010(1).DOI:10.3969/j.issn.1002-1841.2010.01.017.
[3] 張文洋.基于WSN的鐵軌監(jiān)測(cè)設(shè)計(jì)與仿真[D].大連理工大學(xué),2011.DOI:CNKI:CDMD:2.1012.276150.