Ergebnisse für
Am running multiple sensors in the field producing strings of data then sending them to a node. The node is an Arduino Uno on which SIM 800 is attached for internet connectivity. After computation, the result is several strings that i want to display to things speak. The code i have so far can only upload numerical data. Am in need of help to display these strings in Thingsspeak.Help me.
Dear Team,
I have populated my data on ThingsBoard platform using ESP8266, now I want to read that data using MATLAB Industrial Communication Toolbox. I have written a code for this purpose below,
% Replace these values with your ThingsBoard MQTT broker details
brokerAddress = "ssl://demo.thingsboard.io"; % Adjust the broker address
port = 1883; % Use the appropriate port for secure MQTT
% Replace these values with your ThingsBoard device details
clientID = "";
userName = "";
password = ""; % Leave empty if not required
% Replace this with the path to the root certificate you downloaded
rootCert = "";
% Create an MQTT client
mqClient = mqttclient(brokerAddress, 'Port', port, 'ClientID', clientID, ...
'Username', userName, 'Password', password, 'CARootCertificate', rootCert);
% Check if the connection is established
mqClient.Connected
% Expected output: ans = int32(1)
% Subscribe to the telemetry topic
topicToSub = "v1/devices/me/telemetry";
subscribe(mqClient, topicToSub);
% Wait for a while to receive messages (adjust the time as needed)
pause(60);
% Peek at the MQTT client to view received messages
peek(mqClient);
% Close the MQTT client
clear mqClient;
%%%%__________________Output Result______________________%%%%%
>> MQTT_Receive
Warning: Using a port that allows unencrypted communication. For confidential matters, considering using an encryption
enforcing port, such as 8883.
Error using MQTT_Receive
Failed to establish a connection with broker "ssl://demo.thingsboard.io".
I desperately seeking your assistance in this regard
Hello,
I have to draw root-locus for longitudinal motion; Short Period Mode and Phugoid Mode. Here is a code
%% Dynamics
Vp = 111.174
A_lon = [-0.0283 0.3139 -11.0665 -32.0344;
-0.4204 -1.5452 108.6931 -3.2616;
0.0205 -0.2011 -3.5080 0;
0 0 1 0]
B_lon = [0.0115 0.1150;
-0.2185 0;
-0.3591 0;
0 0]
C_lon = [1 0 0 0;
0 -1 0 Vp]
%% LQR Servo Design
A_servo = [A_lon zeros(4,2);
-C_lon zeros(2,2)]
B_servo = [B_lon ; zeros(2,2)]
n = 100; a = logspace(-2,2,n);
for i = 1:n
Q = a(i)*[1 0 0 0 0 0;
0 1 0 -Vp 0 0;
0 0 0 0 0 0;
0 -Vp 0 power(Vp,2) 0 0;
0 0 0 0 1 0;
0 0 0 0 0 1];
R = eye(2);
[K,S,P] = lqr(A_servo,B_servo,Q,R);
p_cl = P;
cl_sh(i,1) = p_cl(5); cl_sh(i,2) = p_cl(6);
cl_ph(i,1) = p_cl(3); cl_ph(i,2) = p_cl(4);
end
%% Plot
figure;
plot(real(cl_sh(:,1)), imag(cl_sh(:,1)), '+', real(cl_sh(:,2)), imag(cl_sh(:,2)), 'x', MarkerSize=5);
title("Root Locus of Short Period Mode")
xlabel("real")
ylabel("imag")
grid on;
figure;
plot(real(cl_ph(:,1)), imag(cl_ph(:,1)), '+', real(cl_ph(:,2)), imag(cl_ph(:,2)), 'x', MarkerSize=5)
title("Root Locus of Phugoid Mode")
xlabel("real")
ylabel("imag")
grid on;
When the code is executed, the sequence of eigenvalues is misaligned from some point in the iteration statement and the point was depended on weight of Q, R matrix. So when the sequence of eigenvalues is out of order from a certain point in time like this, how should we modify the code to solve it?
I'm logging data which I'd like to see on a daily basis. ie each day the chart x axis resets to 12midnight to 12midnight for the current day and just shows todays data. Is this possible please ?
Hello everyone. I'm beginner at MATLAB and I have 12 lead ECG database for my project. I have to see and investigate ECG signal but I couldn't find how to do it. Does anyone know how to combine these 12 lead data and obtain a clear ECG?
Hi,
I am now to appbulding, however I'am trying to build a app with appdesigner, but I cant find out how to change baground color of tree subnode and how to change color of text in subnode.
Is it even possible in appdesigner or in Matlab?
Or can I somehow use html to do this?
Can you help me find the solution?
Thank you very much.
Hello,
What is the difference between a moving angle and a normal angle?
Compute the Rotation about Y-axis over moving angle a = 30°
then
rotation about X-axis of angle β= 45°
What will the code like?
Thank you
Hello everyone, I'm using Simulink for running simulations, and I'd like to call a trained machine learning model (in my case, a TreeBagger) in MATLAB to make predictions in Simulink. However, I'm having some trouble with it. Has anyone already worked with this?
Hello there, I have a Amesim Black box model in Simulink. On my desktop, it works well. Also i tried to run on other desktops. Most of them work well. But some of them gives following error: Error in 'Model' while executing C MEX S-function 'Model', (mdlInitializeConditions), at time 0.0. Caused by: in Simcenter Amesim mexfunction: 'Model', Simcenter Amesim fatal error Cannot initialize Simcenter Amesim Model. EXIT This is an urgent case for me. Could you please help me?
Thank you so much.
Dear Community,
I am trying to perform PowerGUI Loadflow analysis for EV Charging station. The model converges but the load flow vaues on the DC bus is zero. Whether power_loadflow supports Mixed AC/DC load Flow.
Can someone help me by providing guidance on how to preform the same
Regards
Vara
when I build the model I get the name mismatch error for two calibratable signals . The signals are in the data dictionary , and I use them in the model by pulling from the dd with the same name . can anyone point me out what possibly cause this error?
Hi all,
The question is simple as the title says. How to consume messages from selected Kafka topic?
I have a setup which works perfectly from terminal and now I am trying to connect MATLAB with this Kafka topic, just to consume messages. I followed this:
but unfortunately there is no information how to consume messages. Any help will be appreciated!
How to write a script for single mpc controller to multiple sysytems? then plot the response in same graph and differentiate the system dynamics.The above figure for PID likewise for MPC anf commands or codes?
I'm plotting an error with respect to the number of points used.
Now there are three different ways to comput the error, and I always plot the maximal error.
If the maximum is for computation 1, I want the dot in the plot to be red, for computation 2 it should be blue, etc.
How can I achieve this? My data is in a n x 2 matrix
It is crucial to understand that this expression could be used in problems related to engineering, physics, mathematics, or any other aspect of real life.
Typically, Matlab is used to solve PDE and ODE problems. Perhaps users calculated this term 0^0 incorrectly in the process.
>> % Reviewed by Bewar Yousif Ali
>> % How to fix this problem 0^0 in Matlab !?
>> % Mathematically, x^0=1 if x≠0 is equal 1 else undefined(NaN)
>> 0^0
ans =
1
>> f=@(x,y) x^y;
>> f(0,0)
ans =
1
>> v=[2 0 5 -1];
>> v.^0
ans =
1 1 1 1
i=dsolve('Dy=-8*y+40*sin(8*t)','y(0)=5')
Warning: Support for character vector or string inputs will be
removed in a future release. Instead, use syms to declare
variables and replace inputs such as dsolve('Dy = -3*y') with syms
y(t); dsolve(diff(y,t) == -3*y). > In dsolve (line 126)
Hi all, I have to train a one class SVM for anomaly detection. I have a dataset with two features. I trained the model on normal instances with ocsvm function. What I don't understand are the contour lines for the ocsvm scores... I do not expect those to be like that. In the figure are represented the normal instances in the space (feature1, feature2) and the contour lines corresponding to some values of ocsvm score. They are simply absurd, not like the example see on the matlab guide. I would expect ellipsoidal contour lines, not these! Any help? Thank you!
I have a few ESP8266 running various sensor tasks, and sending GET or POST requests to Thingspeak via api.thingspeak.com. They all connect to the household router.
Recently, I became aware of a problem with the devices occasionally timing out when trying to communicate with Thingspeak. For example, here's a bit of code from a basic water level sensor:
String url = "http://api.thingspeak.com/update?api_key=xxxxxxxxxxxxx&field1=";
url += getdistance();
url += "&field8=";
url += batt;
http.begin(client, url);
int httpcode = http.GET();
Serial.println(httpcode);
String payload = http.getString();
Serial.println(payload);
http.end();
Fairly often, the connection will fail with a -1 httpcode. Sometimes it will run for weeks with no issues and then suddenly stop connecting. If I type the URL in a browser, it will always work immediately. If I connect the ESP to a mobile hotspot, it will also connect immediately with no issues. I can't find any issues at all with the router, and I've fully reset it etc. I've also confirmed the wifi connection between ESP and router is not the problem.
Sometimes one ESP will be running fine, and another will be having connection issues. The next day, the first one will have issues and the other will be fine.
So I added a bit of code to see if I could time the connection:
server = "api.thingspeak.com"
timer= millis();
while(client.connect(server,80)){
delay(10)}
t=millis()-timer;
Serial.print(t);
The devices now connect every time. But the connection can take up to 180 seconds. Some ESP's updating to older channels are much more reliable and connect within a second or two; it seems as though the more recently created channels take longer to connect to.
I'm reaching out here because I can't really think of where to begin trying to fix this. Why does a browser succeed immediately updating a channel with the api.thingspeak url but the ESP takes up to 180 seconds? Why do I not have any problems connecting the ESP via a mobile hotspot? Why does the same device work for weeks then suddenly play up?
I think I've isolated the problem to either the router or the thingspeak api, and I can't find anything wrong with the router.
Might be worth noting that I have an ESP in a heat pump which updates every 15 seconds to thingspeak by MQTT and it hasn't skipped a beat in months so maybe I should upgrade them all to MQTT.
Is the api just that flakey?
Error using matlab.ui.control.internal.controller.ComponentController/executeUserCallback Error while evaluating Button PrivateButtonPushedFcn.
help to solve this error in face recognition GUI
Hi I have a user defined blocks for my Simulink but whenever I add path of user defined, the error pops up stating I dont have stateflow.
Can anyone please guide me through it.
