If you have followed my last three posts, you should have:
USB Flash Drive with AR Drone
If your compiled libraries are too large to be stored in AR Drone’s internal memory, you will need to use a USB drive. Make sure that the USB drive is formatted with fat32 filesystem. I have heard that a lot of people have problems getting AR Drone to recognize the flash drive. I have gotten lucky in this regard, both my Kingston 16 GB and a Chinese No-Name 8 GB USB flash drives have worked flawlessly with AR Drone.
After you have plugged in the USB to the Drones USB port, wait for about 15-30 seconds for the Drone’s firmware to auto-mount the drive.
You can run the following simple command to see a list of file systems in a human readable format.
I get the following list:
Filesystem Size Used Available Use% Mounted on ubi1:system 26.3M 14.1M 10.9M 56% / tmp 57.7M 688.0K 57.0M 1% /tmp dev 57.7M 0 57.7M 0% /dev ubi0:factory 4.8M 76.0K 4.5M 2% /factory ubi2:update 13.2M 28.0K 12.5M 0% /update ubi2:data 53.5M 8.1M 42.7M 16% /data /tmp/udev/dev/sda1 7.6G 1.8G 5.8G 23% /tmp/udev/dev/.mnt/sda1 /tmp/udev/dev/sda1 7.6G 1.8G 5.8G 23% /data/video/usb0
Notice the last line. It means that my 8 GB usb flash drive in mounted to
/data/video/usb0. I can navigate to this directory and see the contents of my flash drive.
Configuring the Linker
You have your cross-compiled binary and the shared libraries on the USB. Now all you have to do is to configure the dynamic linker so that it can see the libraries on your flash drive. The dynamic linker loads and links the shared libraries from the path specified by the environment variable
$LD_LIBRARY_PATH. So we just need to add the path to lib folder in our flash drive to
Running the Program
Now you can simply run the program like so:
Terminating the Program
If your program is in an infinite while loop, and you want to stop the program,
Ctrl + C will not work here. If you want to exit a program you will need to kill the process.
Get the list of running processes with
you will get a list like the following
1176 root 2740 S /bin/sh 1229 root 43264 R ./AR_embedded 1259 root 2604 S sleep 10 1260 root 2740 S /bin/sh
my program AR_embedded has process ID of
1229, now that I have noted the ID of the process I want to terminate, I can go ahead and kill it