Ray.Edgley's blog

How do we use ProgramAB

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So the question came up in the forums about repedative questions to the ProgramAB.
So I started to look at the call for starting and using the ProgramAB service.
 
In the Manticore version, this is the example code:
 
#########################################
# ProgramAB.py
# more info @: http://myrobotlab.org/service/ProgramAB
#########################################
 

Install Bug

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In the past whenever I have installed MRL on a Raspberry Pi or even in Windows, I would create a dirctory MRL, copy the myrobotlab.jar file into that director, then open a terminal window and navigate to the directory.

From there I would run the command:

java -jar myrobotjab --install

After some time, particularly on a new build with a fresh OS image, the program would finish and leave me at the command prompt.
Launching then without the --install would start MRL up with all the services installed.


Fixing Audio Output with Java 11 on the Raspberry Pi

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Notes for when running on the Raspberry Pi with the Rasbian Buster OS.
 
When using Java 11 OpenJDK, you may find the audio from the Text To Speech coming out the HDMI port instead of the selected 3.5mm Audio socket on the side of the Raspberry Pi.
This is caused by Pulse Audio not following the requested settings and routing the audio from the Java apps to a different output, the HDMI like it or not.
The solution is to edit the Java sound.properties file.
 

MPU6050 Testing Matrix

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MPU6050 Controller  OS ver  MRL ver Pi4J ver
Raspi 3 No Worky Buster 1.1.446 1.2
Raspi 4 No Worky

Pulling what's left of my hair out

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Been trying to get the MPU6050 6 DOF accelerometer/gyroscope working in MRL.

I can get it to attach and even return some data, except the data doesn't make sense.

With the MPU6050 held stationary, the should always be an acceleration in the downward direction of 1G or between 9.8 and 10 m/s depending on where on the planet you are located. (the lower value closer to the equator)
There should also be a constant low speed rotation of about 0.00416 degrees per second (the planet turns fully once per day)


Experimenting with the NeoPixel arrays on MRL.

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Most builders of the InMoov robot have eventually installed the NeoPixel ring with 16 Pixels in the stomach.
When working, these little multi colored LED unit can look very impressive.\
As Part of Fred's program, I also wanted to use these marvelous devices.
Of course I had to be different :-) and add extra NeoPixels to the ring.

NeoPixels and Ultrasonic sensors working together

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For a long time you could not run ultrasonic sensors on the same Arduino as the NeoPixels.
 
This was because the sleep function in the Arduino would upset the NeoPixel communication control.
In the recent versions of MyRobotLab Nixie version, this issue has now been solved.
 
What you are seeing here is 23 NeoPixels running with 2 active UltraSonic sensors and a Passive Infra Red sensor all on the same Arduino Nano running under MRL control.
 

 


Who said you can't run YOLO on a Raspi

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Testing Freds new program on the Nixie build 1.1.429.

 

 

Good news is it's working :-)

While I was in there, I started OpenCV, loaded the PyramidDown Filter and the Flip filter.


A bit about Fred_Inmoov

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Frequently Re-Engineered Device (FRED)
 
Fred is a modified InMoov Robot.
You can find the videos showing his contruction here:
https://youtube.com/playlist?list=PLgXTfFM40HqEbnFfhaLPmLv_RS1ZRCilI
 
In the Official build of InMoov, http://inmoov.fr/

PID Loops

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Proportional, Integral and Derivative or PID control systems have been around for a very long time, but they are still not very well understood.

Recently I convinced Fred to give a bit of a talk on the subject.
Good thing with robots, is convincingthem is just a case of programming them :-)

Here is the video of Fred's presentation.

https://youtu.be/KzrUz0WBopw