Dinesh S,
Are you making any modifications to the meta layer?
The log seems to indicate that the init script cannot find several of the basic linux commands that should be available like mkdir and grep. You can mount the SD card into your host machine and look at the root file system to see if these are in one of the bin folders.
Please also check the Ubuntu version and packages installed are OK. The README provides information on these.
Best,
Neeraj