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Blog page on fischertechnik robotics and embedded systems.

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2019
18 January (Playlist) Blog 306

RaspberryPi3 & PiXtend: Starting with the downloaded construction manual (apart from startup-manual and data-sheet) I can start with actual placement..which takes hours. Then, after the c(apacitors), d(iodes) and q (for transistors), I continue with ssh and vnc and find I should replace some software. Click the image to watch the video.

ESP32: First, I try to optimize the 7segment display function, after the errors of last time. After solving this, the LDR needs a solution. An observation leads to a quick solution. Also, a reseat of the ESP32 is needed to make the servomotor work. What's next? Click the image to watch the video.

Hand: Checking on the lift on the hand, it's actually a 2nd pitch. Which needs a modification, a checkout and wiring. But how? What should the algorithm be like with what controlling hardware? Does everything work now? (spoiler: several oopses during overall testing). Click the image to watch the video.

RaspberryPi: Investigating the mystery, I first check the spi on the ADC/MCP3008. Then I go on with the spi-3wire on DAC/MAX522. After also using the Mac, while checking on wiring, a big oops happens. Why? How? A final test shows what? Click the image to watch the video.

Mirft2: Starting with the HSV array, I try with several values for H,S and V to get rid of yellow. At the same time, watching the # of cycles..which make much sense. Finishing again with Blender3D to model the robot. Click the image to watch the video.

Discovery: First checking the trajectory (a mess again), I turn to the algorithm to find that I made a mistake in variable and in algorithm. And why doesn't a if-condition apply, according to the data? Click the image to watch the video.

Arduino Mega2560 S2: Once again: how can I read the pwm that is delivered by Octave? Changing the algorithm, pressing the ft switch and finally adding some more input. Something has to work, right?     Click the image to watch the video.

RaspberryPi2 & ROS: Checking the GPIO using Bash, I find that a comparison with gEDA goes wrong. For some reason, details are missing and wrong. Wiring is wrong too. After fixing, compilation goes wrong. But it runs...how? why? Click the image to watch the video.

BeagleBoard & rollertrack: Starting with adding another angle to the trajectory, I find a problem with the wormgear. But how to solve that? Also, the chain motor should stop during the shift. Then problems set in. Oops. Click the image to watch the video.


11 January (Playlist) Blog 305

RaspberryPi3 & PiXtend: Introduction of the RaspberryPi3 in combination with the PiXtend: an open-source PLC that can operate together. The setup just needs some work. Also, what's with VNC? Click the image to watch the video.

ESP32: First focus is on the keypad: why doesn't it work? Can I work out the schematics? Then, the 7segment display can be optimized in the algorithm. But this gives an unexpected problem. What's with void and int? Click the image to watch the video.

Hand: Focus again on the winch: how to make this work? Will a modification to the hand work? Then the balance: how about a reinforcement of the arm-base? Then an oops with the wiring to the interface. How to solve that? Click the image to watch the video.

RaspberryPi: Trying again to get the MAX522 working using spidev, I decide to update and reboot..and try the MCP2008 DAC. What will happen? Do I need a rewire?  I'm in for a surprise (again) and some food for thought. Click the image to watch the video.

Mirft2: Trying again on OpenCV with values things go bad. Finding other values, what happens? Why? Then: modelling using Blender and close observation reveals I need to change the model. Click the image to watch the video.

Mydfir: Starting with the usual linefollowing test towards objects, I notice something odd in response and direction. Testting with diagnose, something is wrong with the sonar. But how to solve this? Click the image to watch the video.

Arduino Yún: Starting with a short overview, I continue with Octave to get the graphs correct. Then: the lamp mechatronics need improvement to hold the lamp and I find out what's wrong with the flashlight. Oops. Finally, an idea to maybe copy the data to the computer. Click the image to watch the video.

Discovery: Focus is on distance again and trying to get the trajectory straight. But I find that my algorithm isn't effective and contains flaws. Also: what's with ROBOPro again? Click the image to watch the video.

Arduino Mega2560 S2: Focussing on input again, I change the algorithm bit by bit and find out that 0 isn't 0? Time for a switch replacement, but will it make a difference? Another analysis and an small mistake in the schematics. Click the image to watch the video.

RaspberryPi2 & ROS: Starting with another test on GPIO, this time on the Mac. Then, trying to find a solution for the GPIOClass. Finally, back to Mac and GPIO with a camera. Click the image to watch the video.

BeagleBoard & rollertrack: First, checking the switches using Python, since it can't be done properly with the diagnose tool. Then more reconstruction to give the balls more speed for the looping. But will it work out? Click the image to watch the video.


4 January (Playlist) Blog 304

ESP32: First focus: keypad. Does it help to change the algorithm? Then: why do the LCD, motor and LDR not work? Some rewiring leads to an unexpected solution for most. But the keypad still gives some questions. Click the image to watch the video.

Hand: After a short overview: how can the hand be lifted? This simple question starts a new analysis with parts missing and a looming reconstruction of the lower arm. But something has to be done. Click the image to watch the video.

RaspberryPi: For the MAX522 DAC, back to trying Python via the shell, using Mac as well. Is there any logic in what happens? Will some rewiring bring a solution? The live+4 seconds videostream is nice, but a bit ....  Click the image to watch the video.

Mirft2: Focus starts on connecting: will it go fine this time? Then, OpenCV and HSV: what's up with the number of pixels. What about Gimp? Finally, further with modelling in Blender3D and finding some points to improve. Click the image to watch the video.

Arduino Yún: Focus is on the attempt to get data visible from the phototransistor. So new data acquisition, making sure all 100x''s are there. Next: Octave..careful observation reveals a viewing mistake which leads to change in the algorithm. Click the image to watch the video.

Arduino Mega2560 S2: Testing the input from the button, takes some code changes but will it solve the mystery? Then, to signal the next loop of the algorithm, I add another LED and another code bit. Click the image to watch the video.

RaspberryPi2 & ROS: For the GPIOClass.h, I realize this must be a linker issue, so this must be solved in the settings. But how and where? Then, with the Mac, another attempt with Bash for the GPIO with surprising results. Click the image to watch the video.

BeagleBoard & rollertrack: Instead of timing, 2 switches should be added to the wormgear and tthe algorithm changed. Does it work? Diagnose says yes. Then the track needs an adaption which requires a reconstruction. Click the image to watch the video.