Coimbatore

Hello Divya,
Admission in PSG College is done via TNEA, where your board's marks are considered for admission. There is no seperate examination for that. However, have a look at the eligibility criteria if you find yourself eligible then apply for it.

No, it's not a good college.

Hello Sharmila,
PSG-Coimbatore is a highly reputed institution where all the courses will be worthy to study. But it also depends on your interest. Your choice of robotics and automation is really good as in the future, it will be having a good scope.
The link below gives you the cut-off marks for the year 2016:
https://www.cutoffmarks.com/cutoffdetails/2015/psg-college-of-technology-3.php
All the best!

As a student of TSM, my opinion is TSM is better than PSGIM.
TSM: Development Immersion Programme, Rural Immersion Programme, loaded with assignments so that you can easily manage corporate work, ethics and values are given importance. 2016 MHRD rating: 15th,Top B-Schools (All India) Hansa Research Survey: 51st.
PSG: More global exposure, choice-based credit system, experiential learning with games, unique pedagogy .Top B-Schools (All India) Hansa Research Survey: 43rd.
Whatever is the college's resources or ranking, you will have to sweat it out and efficiently utilize it.
Best of Luck! Make a wise selection and work consistently.