HobbyTransform

Good to hear you've got it working. I haven't tried blue lasers, but that would be an interesting direction to go with this project. A suggestion to try, instead of the library and circuit setup as in this instructable try the serial communication that is natively available on the uno, so the rx and tx pins already on the uno; i.e. the transmitting uno's tx pin goes to the laser and the receiving uno's rx pin goes to the photodiode. The code would be different too, if you haven't used the arduino serial communication before, find some tutorials online for that. Compare the results you get from that with the results from using my library and see which one is more reliable for your purposes. I was helping someone use this library once and it turned out that the built in serial communication…

Good to hear you've got it working. I haven't tried blue lasers, but that would be an interesting direction to go with this project. A suggestion to try, instead of the library and circuit setup as in this instructable try the serial communication that is natively available on the uno, so the rx and tx pins already on the uno; i.e. the transmitting uno's tx pin goes to the laser and the receiving uno's rx pin goes to the photodiode. The code would be different too, if you haven't used the arduino serial communication before, find some tutorials online for that. Compare the results you get from that with the results from using my library and see which one is more reliable for your purposes. I was helping someone use this library once and it turned out that the built in serial communication of the uno was more reliable in his case.

Hi, please double check that your baud rate on the serial window matches the one set on the line of receiver code with Serial.begin, i.e. the the unedited example code it is Serial.begin(9600), that can affect the results. Also, for good measure, check that you have the latest version of the Arduino IDE as older versions can mess up your results or be glitchy. Let me know if that fixes the problem.

Hello, the receiver code is actually complete, it just doesn't have many lines of code because most of the work is done in the library files (which are quite lengthy actually).

Hi, no those question marks shouldn't be printing out. Make sure that your baud rate on the serial window matches the one set on the line of receiver code with Serial.begin, i.e. the the unedited example code it is Serial.begin(9600). Also, for good measure, double check that you have the latest version of the Arduino IDE as older versions can mess up your results or be glitchy.

Hi Rickstar2020, I don't have an arduino mega but I assume it would work just the same if you assign more analog pins in the code, just assign more pins and write to them following the pattern I've set out in my code above.To answer your other question about using more than 12 leds:I think you only really need 2 pins because there are only two brightness values in the code: brightness1 and brightness2 and half the leds have brightness1 and the other half have brightness2. If you wire half your leds in series to one pin (assign a value of brightness1) and half in series to another pin (assign it a value of brightness2) you can have more leds flashing in the same manner as this project but you may need to lower your resistor values so you have enough current running to power each led's then…

Hi Rickstar2020, I don't have an arduino mega but I assume it would work just the same if you assign more analog pins in the code, just assign more pins and write to them following the pattern I've set out in my code above.To answer your other question about using more than 12 leds:I think you only really need 2 pins because there are only two brightness values in the code: brightness1 and brightness2 and half the leds have brightness1 and the other half have brightness2. If you wire half your leds in series to one pin (assign a value of brightness1) and half in series to another pin (assign it a value of brightness2) you can have more leds flashing in the same manner as this project but you may need to lower your resistor values so you have enough current running to power each led's then you don't even need a mega, an uno will be sufficient but keep in mind that microcontroller pins have a maximum current output, you have to find the datasheet of your specific microcontroller / development board to get that number.A better setup would be use 2 pins controlling some transistors which power your two strands of leds, then you aren't capped to microcontroller pin current limits. I can only give you this basic idea to point you in the right direction you'll need to search how to use transistors as that is your best option to control a large number of any kinds of loads (leds, motors, etc) using a microcontroller.

Hi pieboy, the code is actually c, which is a subset of c++, so you could rename the .cpp files to .c and it should work fine with a c compiler I think. I haven't tested it with any raspberry pi's but that sounds like a cool project idea, just make sure the laser slew rate can handle the higher bit-rate of transfer as that will affect the accuracy. The photodiode module part number is IS0103 I believe, so you should be able to find a datasheet for that.

Hi, yes the laser sensor module is necessary because the resistor and capacitor that come with it form a low pass filter to filter out noise I believe. Normal photodiodes have 3 pins: ground, vcc and a signal pin. The laser sensor module also has 3 pins because it has the photodiode on it.

Yes only use the recommended photodiode. A LDR works differently, based on different frequency of light I think. The maximum bit rate for the specific laser you use can be determined by experimenting with different values of bit rate in the code. Baud rate can be calculated from bit rate, I think it this case it would be 44 bits = 1 baud, so divide bit rate by 44 to get baud rate.

Maybe you might be able to get away without changing the library. Try combining the code from the two arduino example files (transmitter and receiver codes) into one file. See what happens.

Doesn't sound like any changes are needed in the code, just connect two lasers to the same data pin and it should work.

You could probably save the data as a string or array and loop over each character or element of the array. In the loop you would just hamming encode each byte and modulate as in the original code.

Hey guys, this question has already been asked a couple of times before. Please scroll through the comment section to find the possible solutions (there may be a number causes for your problem, so I gave a number of possible solutions).

Hi Julian, I think what you are looking for could be the line:delay(30); // wait after resetin the function MPU6050::dmpInitialize() in one of the following files: MPU6050_6Axis_MotionApps20.h and MPU6050_6Axis_MotionApps41.h, which file you have to edit depends on which one is #included in your MPU6050_DMP6.ino file. Maybe you can set the delay to something smaller or even 0 and see what happens. I'm only speculating from looking at the code, I haven't tested any of this, so I'll leave that up to you.

I can't help you until you answer my question: "have you taken a look at the code (i.e. both the included arduino sketch and the MPU6050 library header files)? Can you tell me what part of the code relates to calibration?" Then I can help you out. Please stop repeating your question, I already understand what you are asking.

I presume the capacitor is acting with the resistors as a low pass filter to filter out high frequency noise. So in your setup without the capacitor, the noise is coming through along with the signal and causing inteference.

Hi, yes I have tested it multiple times. It seems your problem is most likely on the receiver end. Make sure to use the same model receiver as the one in this instructable otherwise I can't guarantee you'll get the same results as me; my sensor doesn't just have resistors but a capacitor.

Hi Julian, stationary calibration is important because it is the only way for the system to know in what orientation, position and speed it is at any given point later. If you run the initialization phase once and store the offsets for later and skip calibration on each start up, you need to guarantee your setup always begins in that exact same state of motion and orientation for the IMU motion data to be at least approximately accurate.It might be possible to the skip calibration part in the code, have you taken a look at the code (i.e. both the included arduino sketch and the MPU6050 library header files)? Can you tell me what part of the code relates to calibration? Then I can help you out.

To view the simulation on an android smartphone, I would assume you'd need an android compatible arduino IDE (e.g. https://play.google.com/store/apps/details?id=name...) or the web editor (https://create.arduino.cc/editor) and the processing app (http://android.processing.org/install.html), serial data would be received via bluetooth, i.e. transmitted from HC-05 and received by the phone's bluetooth. In theory this setup might work, I leave that up to you to test.For the velocity of the car, you should be able to calculate it from acceleration using integration (velocity is the definite integral of acceleration, initial velocity is 0 m/s, initial acceleration is 9.8m^-2 down) or perhaps the library for the mpu6050 module has a function for calculating velocity, I leave that up to you to f…

To view the simulation on an android smartphone, I would assume you'd need an android compatible arduino IDE (e.g. https://play.google.com/store/apps/details?id=name...) or the web editor (https://create.arduino.cc/editor) and the processing app (http://android.processing.org/install.html), serial data would be received via bluetooth, i.e. transmitted from HC-05 and received by the phone's bluetooth. In theory this setup might work, I leave that up to you to test.For the velocity of the car, you should be able to calculate it from acceleration using integration (velocity is the definite integral of acceleration, initial velocity is 0 m/s, initial acceleration is 9.8m^-2 down) or perhaps the library for the mpu6050 module has a function for calculating velocity, I leave that up to you to find.

To view the simulation on an android smartphone, I would assume you'd need an android compatible arduino IDE (e.g. https://play.google.com/store/apps/details?id=name...) or the web editor (https://create.arduino.cc/editor) and the processing app (http://android.processing.org/install.html), serial data would be received via bluetooth, i.e. transmitted from HC-05 and received by the phone's bluetooth. In theory this setup might work, I leave that up to you to test.For the velocity of the car, you should be able to calculate it from acceleration using calculus (velocity is the definite integral of acceleration, initial velocity is 0 m/s, initial acceleration is 9.8m/s^2 down) or perhaps the library for the mpu6050 module has a function for calculating velocity, I leave that up to you to fin…

To view the simulation on an android smartphone, I would assume you'd need an android compatible arduino IDE (e.g. https://play.google.com/store/apps/details?id=name...) or the web editor (https://create.arduino.cc/editor) and the processing app (http://android.processing.org/install.html), serial data would be received via bluetooth, i.e. transmitted from HC-05 and received by the phone's bluetooth. In theory this setup might work, I leave that up to you to test.For the velocity of the car, you should be able to calculate it from acceleration using calculus (velocity is the definite integral of acceleration, initial velocity is 0 m/s, initial acceleration is 9.8m/s^2 down) or perhaps the library for the mpu6050 module has a function for calculating velocity, I leave that up to you to find.

Hi Alyan, for editting the plane to show a car instead, please refer to Waldo's solution in the comments section further down.For connecting wirelessly to a phone, I suppose bluetooth might be possible (e.g. HC-05 bluetooth module), I haven't tried that so I can't say how you would have to modify the code to do that but have a look at arduino bluetooth tutorials on instructables and maybe combine it with what you've learnt in this one?

Or perhaps you just need to update to the latest version of Arduino, as I see yours is outdated. That's another possible reason for the error, not very likely, but worth updating just in case.

Hi Tarek, at this point I see 3 possible errors:1. Note that there is more than one libraries folder in the Arduino folder, make sure to put my library in ...\Arduino\libraries and not ...Arduino\hardware\arduino\avr\libraries.2. arduino_modified_sketch_373287\receiver.ino, the arduino sketch being used must have the same name as the folder it is in, since they are different, that may be causing error.3. Why is your sketch in the AppData folder? Is that a good idea? I'd move it somewhere else like your Desktop or a personal folder for example and try again.Anyway, I tested it out on my computer by removing the library from ...\Arduino\libraries and compiling the receiver sketch and I get a similar error to you (except that my sketch isn't in the AppData folder but on the desktop).

Or perhaps you just need to update to the latest version of Arduino, as I see yours is outdated. That's another possible reason for error, not very likely, but worth updating just in case.

Hi, have you installed the library? The error you are receiving indicates either the library hasn't been installed (in the libraries folder in the arduino application folder, wherever you've installed the arduino application on your computer) or you haven't restarted the arduino application after installing.

That's a good question, what have you found out about it so far on google?

Hi Tuấn, not yet, I plan to add one and some more pictures / schematics soon. Thanks for asking!

I'll need more information about your setup than that to be able to help you, there is probably a host of reasons why you'd get a random error like that. I can only give you general advice at this point: double check your wiring, make sure you have the latest version of arduino, try an earlier version of the library if the current one isn't working, if all else fails disconnect everything and repeat the instructable from scratch to spot any possible mistakes you've made in setting up the system.

Hi, it's good to see you're experimenting beyond this instructable to see what else is possible with this module. My guess is: see if you can find in the code what is being done with the AD0 pin of the first sensor and try to replicate that behavior independently with the AD0 pin of the second sensor via a separate arduino pin and see what you get.

For bluetooth you have to send / receive the data through serial. Here is a great starting point to help you with the arduino code for HC-05 modules. I learnt a lot through that instructable.

Hi, this depends on what type of rf transmitter you want to use. There are many options such as 433MHz or 315MHz modules, bluetooth (e.g. HC-05 or HC-06), WiFi (e.g. ESP8266), XBee or even Zigbee. The simplest to use are probably the bluetooth modules in my opinion.

I've started writing the code ages ago. The main issue that's was delaying me was hardware related, but it's been sorted now. I'll be posting an instructable when it's complete. Stay tuned.

The map function is simply a math function to linearly map from one range of values to another, it can be used in many different contexts, analog was just one specific example. So if you have a gyro value, say gy, mapping from (-180,180) to (0,360) would look like: gy (or some other variable like gy_new) = map(gy, -180, 180, 0, 360).

Maybe one of the pins hasn't been soldered on properly? Double check that enough solder was used to make a clean connection. Or maybe the particular usb port used with the arduino was faulty? You could try another usb port on your computer. If those aren't the issue, there might also be a solution on the ic2dev forum (the link is somewhere in the comment section).

Try the arduino map function: https://www.arduino.cc/en/Reference/Map

Hi,Can you please copy and paste the entire error message here? I'm not sure this file is even relevant because I haven't found it on my computer or in the library folder MPU6050.

Hi, glad you found it useful.To print yaw pitch roll values, you'll need to add Serial.println(...) lines to the code. For saving files through arduino, I haven't done it before but it's probably a similar process as done in the C language, i.e. using fopen and fclose functions. Check here for an example: http://www.tutorialspoint.com/c_standard_library/c_function_fopen.htm. Google is your friend, that's where I would start.

Cool, it sounds easier than I thought. I might try it out some time.

Hi Julian,I agree with Waldo's idea, that's how I would start:1. Go to the #ifdef OUTPUT_READABLE_YAWPITCHROLL section of the void loop() function2. save the most recent values to temp variables, y_old, p_old, r_old...3. get the next values and save them: y_new, p_new, r_new...4. use an if statement rather than a while statement: if(y_new - y_old > y_tol || p_new - p_old > p_tol || ...){PRINT VALUESDO OTHER STUFF}5. replace the old values with the new valuesI leave it to you to decide how to handle the very first values recorded.

Hi Julian,I agree with Waldo's idea, that's how I would start:1. Go to the #ifdef OUTPUT_READABLE_YAWPITCHROLL section of the void loop() function2. save the most recent values to temp variables, y_old, p_old, r_old...3. get the next values and save them: y_new, p_new, r_new...4. use an if statement rather than a while statement: if(y_new - y_old > y_tol || p_new - p_old > p_tol || ...){PRINT VALUESDO OTHER STUFF}5. replace the old values with the new valuesI leave it to you to decide how to handle the very first values recorded.

Hi, you mean the code for a quadcopter? I don't have one yet, but I will be writing it soon, I've just been in the process of gathering all the parts I need for the quadcopter. So stay tuned as I am planning to post an instructable on making an arduino quadcopter soon.

Hi Ainel,Apologies for the late reply, I was trying to find a solution to your answer online but I haven't found anything. If you're still looking for a solution you can either experiment with the code to see if there is a way to start printing data automatically, or if there isn't a way and that's just how the arduino serial window works, maybe you could experiment with other serial windows like PuTTY or Tera Term. Hopefully you find something that works, but if not it shouldn't matter too much because the serial window is mainly for debugging your project so when you send the data through an XBee there probably won't be a need for Serial Begin / Write / Read in your code.

Actually the link I posted in this instructable is correct, it is the official repository for "all current and future releases" as stated by toxiclibs.org.

No worries, if you happen to find a solution please post here for the benefit of anyone else who might be experiencing the same problem. Thanks!

Hey Gabriel, at this point I think your chip might be broken and you may need to get a new one. But just in case it's not, you could try asking for a solution on this forum: http://www.i2cdevlib.com/forums/. If that fails, then just get a new chip.

Hi Gabriel, based on the motion response in the simulation in your video I'd say it's working fine but with a weird offset in the pitch angle for some reason, perhaps there was a slight misalignment when the chip was being manufactured which is causing the offset. I think you should be able to compensate for that with a simple fix: find the line of code (in the arduino sketch) that says// supply your own gyro offsets here, scaled for min sensitivityAnd adjust the appropriate X, Y, Z Gyro offsets accordingly. It might take some trial and error. Let me know if that works.

What do you mean?

Hi, I haven't looked at other simulations but it sounds interesting, especially arducopter. To find out if other simulations exist and how to do them, I would just search on google and youtube. That's how I learnt about the MPU6050 simulation before I made this instructable.

Hi Kitu,It sounds similar to some of the problems others have been posting in the comment section here. Have a read through the comments and you might find a solution that works for you.

I've just re-downloaded the library and repeated the process outlined in my instructable and there doesn't seem to be any compilation errors. A possible reason why you are getting an error is a very subtle mistake you may have done in step 2: in renaming Adafruit-GFX-Library, make sure you have used _ instead of -.

Hi, did you make sure to restart the arduino application after editing the .h file? So maybe close arduino then reopen it and then compile and upload.

No worries, glad to help.

I just found a similar question on the ic2devlib forum, answered by Jeff Rowberg himself where he explains what the raw output of the accelerometer / gyro mean.

That's awesome! I will release an instructable when I'm done (currently in the designing / building phase), be sure to follow me so you know when it comes out. I've got a list of other projects I'm planning to release soon if you're interested.

I've had a look at the comments in the MPU6050.cpp library and it looks like the acceleration is g.

Hi,did you make sure to select the correct COM port before uploading? Also double check the wiring is correct, e.g. SCL / SDA not XCL / XDA. If that's still an issue, try an earlier version of the ic2dev library, like January 4 (the link to that is in the one of the comments).

Hey, what a coincidence! I'm also making an arduino quad from scratch! Hi 5! Haven't started yet though, just received all the parts in the mail.Your printed values don't seem too bad to me, it looks like only small changes when the device is stationary, that happened to me too. I think you'll simply have to set a tolerance level (e.g. #define tol ...) for your ypr values so that if they change by more than the tolerance, then it can be interpreted as actual motion and not just noise.There's another person I've come across who's making a quad from scratch using the MPU6050. You might find some useful notes there: https://hackaday.io/project/6671-quadcopter-from-scratch

Hi, if you want to communicate with your laptop there are several options even besides this 433MHz module. For example, you can communicate via bluetooth (e.g. using the HC-05 module, here is a good starting point) or via WiFi (e.g. using the ESP8266, the version 3 module is probably best but I'll have to test it when I get the chance).

Thanks! I managed to get it working on my computer. I used PuTTY instead of Tera Term.