I want to build a automatic stopwatch for dog agility.
It's not very accurate to start and stop time with a ordinary one.
I need a sensor on the first jump and another sensor on the last jump.
The first start time and the second stop time.
And then view time on a display or so.
I found this project that is alike what i want.
https://www.hackster.io/falafelsoftware/ir-break-beam-hot-wheels-car-speed-track-361455
The sensor used in this Adafruit Breakbeam Sensor
https://learn.adafruit.com/ir-breakbeam-sensors/overview?view=all
If i understand it correctly the range is only up to 50 cm.
A jumps width is normally 120 cm but it can be up to 140 cm.
So i need at least 120cm range.
I want to use a raspberry Pi and windows C#.
I have experience with c# and visual studio but this will be my first IOT project.
I am very thankful for any help and tips to build this.
Specially tips on a sensor that will work for me.
Related
I currently have firmware that can reach an average deep sleep current of ~130uA. I can reach this level reproducibly on one of the boards I have.
successful deep sleep
Trouble is, when I try to clone this chip onto other chips using the nRF Programmer (Connect) app, I get extremely high power consumption, average of ~20mA at all times, seems the device doesn't reach deep sleep properly. Tried this on several other boards, so I don't believe it's simply a problem of something shorting. Strangely, the application just runs fine, the current is just several times normal for the same functionality.
unsuccessful deep sleep
Does anyone have any ideas on how I can truly clone the flash of one device, onto another? Clearly the "save as file" on nRF Connect isn't doing this. Erasing all and reuploading, starting from a blank chip and writing,
FYI I'm using the nRF52840 module by Raytac (MDBT50Q), implemented on a custom board. This board SHOULD be capable of going down to ~33uA, which I have observed in the past with this very board. By some combination of erasing all, reprogramming, setting the 3.3V logic level(nrfjprog --memwr 0x10001304 --val 5), etc,
For posterity, I did actually find the solution! For anyone else in a similar boat to me, the winning command is:
nrfjprog.exe --readcode --readuicr --readram [filename.hex]
Apparently, the --readram was the winning flag, as without it the sketch simply doesn't run at the same current consumption for whatever reason. But now, I can reproducibly image and transfer identical firmware, which was what I was after.
I want to make home automation system for my final year project. One module of my project is light ON OFF on entrance, for that purpose I used IR sensor but the range of IR sensor is 20cm which is not suitable for my project, i need minimum 4 feet ranger to detect the human to turn ON OFF light. anyone suggest me to which sensor is best for that.
Thanks
You csn use what's called human sensor, it is very sensitive and provide the on off signal you need, low cost, easy to use ans small enough to fit inside any sensor enclosure.
I'm trying to get arduino uno to sequentially extract liquid from each of four chambers to a main chamber using solenoid vales, flowmeter, level sensors, and a centrifugal pump. process being open main tank solenoid valve, open valve one, extract quantity one, close valve two, delay 1 second, open valve two....
Does anyone know the best way to go about programming this? I have no coding experience outside of mathematic analysis. Trying to get it directly in the Arduino IDE. I'm also at the same time checking liquid levels and controlling temperature.
You should do one step at a time. Your project is pretty ambitious as a first project.
I would suggest going first for some small examples like letting a LED blink, using a button etc. to get a feeling for the IDE and C syntax.
When you feel confident enough with basic programs you can progress. I'd suggest to go one sensor/actuator at a time. Trying to communicate with it and verifying the data.
But keep in mind this won't be just a coding project but there will be a substantial mechanical/electrical part. Especially when dealing with liquids there are a ton of different hose diameters, voltage levels, etc.
You have to work out how to power the pump and valves safely, because the Arduino board can't handle greater currents.
If you really want to go into this project, you surely can. But keep in mind that this won't happen in a week. To get this working properly you probably will have to invest months and educate yourself not only on the programming side, but also on the electrical side.
I am working on a project that requires me to use 2 separate Arduinos running independently from each other. Now, both of these Arduino's are running the same code, but I noticed that after 10 minutes or so, one of them falls behind and this time difference keep increasing with time. Like I already mentioned, the Arduino`s are identical and I bought them at the same time and they are running the same copy of the program. Any ideas what might cause this and how can I fix it?
Thank you.
Here is the link to the Arduino that I bought just in case.
My Arduino modules on Amazon
The Crystal Oszillators have tolerances up to 100ppm (extreme case), which means you could possibly get 16Mhz*100ppm = 1600 clock pulses difference per second. Also the differences of the runtime could be caused by small voltage differences. Even if there is a voltage Regulator on the Board it has small tolerances, based on the fact, that it operates in the Range of MHz this can climb up to an recognizable Offset.
A possible solution is a synchronization of both microcontrollers. I'm not an expert, so the following solution is a possible and easy one, but definitly not the best.
If they are near by each other you can use two pins of each controller. One as Input and one as Output. Write something like this in your code (same for both if you use the same Pins):
digitalWrite(outPin, LOW);
while(digitalRead(inPin)){};
digitalWrite(outPin, HIGH);
Connect the Output from the first to the Input from the second and the same from second to first.
This results in a waiting state for each cycle of the faster Controller until the slower one reaches the same Programm Part. But be careful if one of them stucks somewhere it will stop the second one too. So there is no redundancy! if this was your goal, don't use this method and search for other synchronisation methods.
Perhaps you can use some RTC (real time clock) hardware to help you to keep they synchronised. They are really cheap and easy to use.
I am working on a drone project and currently choosing a board to use. Is it possible to use an Arduino Nano for all needs which are:
Gyroscope and Accelerometer
Barometer (as an altimeter)
Digital magnetometer
WiFi (to send telemetry for processing)
GPS module
4 motors (of course)
P.S:
I know nothing about Arduino. However I have a good ASM, C/C++, programming background and I used to design analog circuits.
I would like to avoid using ready-made flight controllers.
Pin count should not be too much of an issue if using I²C sensors, they would simply all share the same two pins (SCL, SDA).
I agree that the RAM could be a limitation, the processing power (30 MIPS for an arduino uno) should be sufficient.
On an arduino mega, the APM project ran for years with great success.
I believe it's possible to do a very simplified drone flight controller with an Arduino nano and several I²C sensors + GPS.
But even with a more advanced microcontroller it's not a trivial task.
*** If you still want to try the experiment, have a look at openlrs project : https://code.google.com/p/openlrs/ . It's quite old (there are several derived projects too), but it runs on a hardware similar to arduino uno (atmega328). It provides RC control, and quad flight controller with i²c gyroscopes, accelerometers (based on wii remote), and barometer.
It also parse data from the GPS, but afaik it doesn't provide autonomous navigation but it should be possible to add it without too much additional work.
edit : about the available RAM.
I understand that at first sight 2kb of RAM seems a very small amount. And a part of it is already used by Arduino, for example the serial library provides two 64 bytes FIFO, using some RAM. Same for the Wire (I²C) library, although a smaller amount. It also uses some RAM for stack and temporary variables, even for simple tasks such as float operations. Let's say in total it will use 500 bytes.
But then what amount of RAM is really required ?
- It will have a few PIDs regulators, let's say that each one will use 10 float parameters to store PID parameters, current value etc. So it gives 40 bytes per regulator, and let's say we need 10 regulators. We should need less, but let's take that example. So that's 400 bytes.
-Then it will need to parse GPS messages. A GPS message is maximum 80 bytes. Let's allow a buffer of 80 bytes for GPS parsing, even if it would be possible to do most of the parsing "on-the-fly" without storing it in a buffer.
-Let's keep some room for the GPS and sensors data, 300 bytes which seems generous, as we don't need to store them in floats. But we can put in it the current GPS coordinates, altitude, number of satellites, pitch, roll etc
-Then some place for application data, such as home GPS coordinates, current mode, stick positions, servo values etc.
The rest is mostly calculations, going from the current GPS coordinates and target coordinates to a target altitude, heading etc. And then feed the PIDs to the calculated pitch and roll. But this doesn't require additional RAM.
So I would say it's possible to do a very simple flight controller using 1280 bytes. And if I was too low or forgot some aspects, there's still more than 700 bytes available.
Certainly not saying it's easy to do, every aspect will have to be optimized, but it doesn't look impossible.
It would be a trick to make all of that work on a Nano. I would suggest you look at http://ardupilot.com/ they have built a lot of cool thinks around the ARM chip (same as an Arduino) and there are some pretty active communities on there as well.
Even if you didn't run out of pins (and you probably would), by the time you wrote the code for the motors and the GPS, you will run out of RAM.
And that's not even getting into the CPU speed, which is nowhere near enough. As mentioned in the other answer, you'll be better off with a Cortex M-x CPU.
Arguably, you could use a few Nanos, one per task, but chaining them together would be a nice mess...