Dr. Babasaheb Ardinmbedkar is known as the Architect as well as the father of the Constitution. The crucial task of presenting the draft to the Constituent Assembly, of replying to all the queries as well as of revising the original draft according to the suggestions of the Constituent Assembly was shouldered by Dr. Babasaheb Ambedkar. Due to this fundamental contribution in the making of the Constitution, Dr. Babasaheb Ambedkar is rightly known as the Architect and the Constitution of India and the Government of India honoured Dr.Ambedkar by awarding India's highest civilian award the 'Bharat Ratna' in the year 1990, posthumously to the architect of the Indian Constitution, which came into force from 26th January 1950. 

B.R. Ambedkar is known as the father of the Indian Constitution. He played a major role in framing the Indian Constitution and is considered as one of the most important figures in Indian history. Ambedkar was a social reformer, economist, and jurist who fought for the rights of the Dalits (untouchables) and other marginalized communities in India.

Ambedkar's contribution to Indian Constitution:

1. Chairman of the drafting committee: Ambedkar was the chairman of the drafting committee of the Constituent Assembly, which was responsible for drafting the Indian Constitution. He played a key role in formulating the principles and provisions of the Constitution.

2. Advocate of social justice: Ambedkar was a strong advocate of social justice and equality. He fought against the caste system and worked towards the upliftment of the Dalits and other marginalized communities.

3. Architect of fundamental rights: Ambedkar is known as the architect of fundamental rights in the Indian Constitution. He was instrumental in drafting the provisions related to fundamental rights, which guarantee the citizens of India certain basic rights and freedoms.

4. Advocate of federalism: Ambedkar was also a strong advocate of federalism. He believed in the distribution of powers between the Centre and the states and worked towards ensuring a strong federal structure in the Indian Constitution.

5. Advocate of secularism: Ambedkar was a firm believer in secularism and worked towards ensuring that India remained a secular nation. He played a key role in drafting the provisions related to secularism in the Indian Constitution.

In conclusion, B.R. Ambedkar's contribution to the Indian Constitution is immense. He played a vital role in framing the Constitution and ensuring that it reflected the values of justice, liberty, and equality. His legacy continues to inspire generations of Indians to fight for their rights and work towards a better future for all.