After testing various fan-driven possibilities and having no progress in texture sensing of a desert, I started to spread other ideas around MIDI controller, in the thinking process of project 2, I also gave up a plan applying color sensors. So it's an opportunity to explore color instruments for this project, and what I have in my hands is an RGB sensor named TCS3200 from DFROBOT.
First time I tried to implement the MIDI controller example from Tom on Uno because I thought Uno is more powerful to drive the sensor module. But I encountered an unknown error like below, then I moved everything to Nano 33, the error didn't jump out again.
Then I met a huge obstacle that took up me so much time to debug: any Digital Audio Workstation couldn't play notes even they showed my Arduino connected. I checked every wire in mentioned MIDI controller circuit, as well as added returned numbers in the serial monitor, which proved nothing wrong on the physical end.
Since the hardware had no problem, so did the software, I moved to check the code. Finally, I found the following function actually didn't send MIDI messages out to DAW:
void midiCommand(byte cmd, byte data1, byte data2) {
Serial1.write(cmd); // command byte (should be > 127)
Serial1.write(data1); // data byte 1 (should be < 128)
Serial1.write(data2); // data byte 2 (should be < 128)
}
The bug was removed after I added following two lines from Tom's one-key MIDI player example:
midiEventPacket_t midiMsg = {cmd >> 4, cmd, data1, data2};
MidiUSB.sendMIDI(midiMsg);
https://player.vimeo.com/video/488921475
I made a two-sides color disk, including yellow, orange, red, black, green, blue, purple, white(my Airpods instead...) to test the sensor range. As the video shows, the initial ranges are very crowded, so I mapped them into 510~0(2*255[RGB values]) to get a more visible difference.
https://player.vimeo.com/video/488917323
Then I suddenly realized the most flexible moving tool to sense colors is the human hand. So I converted the position relation between the color disk and the sensor module. Below glove born. In consideration that I have to use one hand to take process videos and photos, I only made a one-hand glove with five colorful finger caps, one black pad in the palm of my hand, and one white pad on the back of my hand.
