Pi Robot Kit - Camera Not Working?

[Alan]

Hi there,

Glad you got the camera working in the end. I appreciate how frustrating it can be to spend hours and days on something that turns out to be a simple fix, but unfortunately to a certain extent, that is part of the learning process of electronics, robotics and programming in general. The days I lost mucking up C/C++ #include statements springs to mind.

At Dawn Robotics, we are trying to lower the barriers of entry to robotics, but there's obviously a lot of things that still need work. The Pi Camera Robot in particular, is not really yet a full kit with a manual in the sense of our Rover 5 robot. At the moment, it's more of a blog post that's got a bit out of control. We're working on some refinements and improvements however (clearer instructions and more photos being one of them) that should hopefully improve things in the future. For now, I've added to the part that talks about attaching the camera cable, as per your suggestions.

With regards to the camera going dark, this is an intermittent bug that I've seen which is usually solved by restarting the robot. This is either a problem with raspistill, or more likely a problem with the way we're using it in camera_streaming.py. Either way, this is a software issue which is hopefully a bit more up your street. I've created an issue on the Bitbucket repository to keep it visible. Also, the problem may be alleviated by trying the robot in an area with different lighting? This post on the Pi forums may also be relevant.

Regards

Alan

[JTeagle]

It certainly looks like the issue is not unique to me... so as long as my camera is not damaged by my error, I'm happy. Now I just have to find some decent learning material on using the Pi and Linux in general as I've never really played around with it before.

[mike1234]

Hi

My RPi Camera Bot was working OK, but I've built up a new image on SD Card (i.e. not copied the whole image) with the 7th May software revisions and the camera doesn't appear to be streaming, and no red light on the camera.
There is sufficient power i.e. motors are powered successfully and the voltage on the RPi is 4.95v.
I've run raspistill -o image.jpg and the camera light comes on and an image is captured !!

Can you suggest what I should look at now?

Thanks

[Alan]

Hi Mike,

Can you try running

raspberry_pi_camera_streamer

and let me know what the results are? The red light should come on when you run this program.

Also, if you get the time, can you try the new image (just to make sure that that works on your robot?). Hopefully it's just some aspect of my instructions for building the card that needs clarification.

Regards

Alan

[mike1234]

Hi Alan

I'll try to run the raspberry_pi_camera_streamer this evening.

However, I probably didn't make myself clear, I am now using the new image. The old one which I bought already installed on one of your SD cards worked OK, I just thought I'd try the new software.
I used your guide http://www.dawnrobotics.co.uk/creating- ... s-sd-card/
This works for the motor control and includes the shutdown button, just no streaming.

I'll post this evening when I've tried running raspberry_pi_camera_streamer on it's own.

Mike

[mike1234]

Alan

When I run raspberry_pi_camera_streamer I get an error message:-
.....can't find '_main_' module in raspberry_pi_camera_streamer....

Mike

[mike1234]

I also think that the motor 'ticking' that someone mentioned on an earlier post means that the motors are continually drawing current and this is draining the batteries very fast, I'm not sure but the power switch on the Arduino board is getting hot, I've tried to measure the current but my multi-meter is playing up.

[Alan]

Hi Mike,

That raspberry_pi_camera_streamer is very odd, the program is written in C/C++, but the error you're getting looks like a Python error.

Assuming that you're downloading it from source and building, can you please try running the following, and sending me the output?

Code: Select all

cd /home/pi/raspberry_pi_camera_streamer
cd build
make clean
make
./raspberry_pi_camera_streamer     # Note the ./ here - this runs the program just built

Now, the alternative to building the SD card image from scratch, which can take a while, is just to flash a prebuilt image to an SD card. To do this you would need to

1. Download 2014-05-07-dawn_robotics-raspbian.img.zip from here

2. Unzip the file to get the .img file

3. Flash the .img file to an SD card using instructions here (go to the section that says 'Flashing the SD card using...' for your operating system

Can you give this a go and let me know how you get on?

With regards to power usage, the servos will draw minimal current (compared to the Pi, and the wheel motors) and so I would say this won't noticeably affect battery life. What batteries exactly are you using to power the robot, and what kind of battery life are you getting out of them? We use Duracell 2400mAh NiMh batteries and get close to 1.5 hours with those.

Regards

Alan

[mike1234]

Alan
You have email. I ran the above but could paste the screen shot here so emailed it. It didn't work. I'll now just copy the ready made image to an sd card and try that.
Mike

[mike1234]

Regarding the current; the switch definitely gets very hot!!!
Mike