Advanced Robotics Week 1 NPTEL Assignment Answers 2026

1. The writer who first used the term ‘robotics’ was

• Isaac Asimov
• Isaac Newton
• Karel capek
• Johanes Kepler

Answer : See Answers

2. Industry 4.0 connects:

• Machines, human and AI
• Human and computers
• Human and AI
• Machines and AI

Answer :

3. A robot is different from a CNC machine because

• it uses AI
• it can sense the environment
• it follows human commands
• it moves around

Answer :

4. The degrees of freedom of revolute and cylindrical joint are respectively

• 1 and 1
• 3 and 1
• 1 and 2
• 2 and 1

Answer :

5. A small cylinder is kept on a table on its base. How many degrees of freedom are required by a robot to pick it up and again place it on its base at another location on the same table?

• 1
• 2
• 3
• 4

Answer : See Answers

6. The work volume of a cartesian robot having three prismatic joints of equal length is a

• Cube
• Cuboid
• Sphere
• Cylinder

Answer :

7. A 3 × 3 orthogonal matrix is used to represent

• position of a rigid body
• orientation of a rigid body
• position and orientation of a rigid body
• none of the above

Answer :

8. The inverse of the rotation matrix is equal to its

• Transpose matrix
• Adjoint matrix
• Co-factor matrix
• Identity matrix

Answer :

9. A frame ‘B’ is rotated by 20o about the Z axis of a fixed frame ‘A’. If the coordinate of a point ‘P’ in frame ‘B’ is given by (1, 1, 1), find its coordinate in frame ‘A’.

• (0.59, 1.28, 1)
• (1.28, 0.59, 1)
• (1, 0.59, 1.28)
• (1, 0.59, 1)

Answer :

10. A frame ‘B’ is rotated by 30o about X axis of frame ‘A’ and translated by (6,6,6) units in the x, y and z directions of frame ‘A’. If the coordinate of a point ‘P’ in ‘B’ is given by (1, 1, 0), find its coordinate in frame ‘A’.

• (7, 6.86, 6.5)
• (7, 6.5, 6.86)
• (1, 6.5, 6.86)
• (6, 6.5, 7)

Answer : See Answers

NPTEL Advanced Robotics Week 1 Assignment Answers 2025

1. The writer who used the word ‘robotics’ was

a. Al-Jazari
b. Satoshi Shegemi
c. Ichiro Kato
d. Isaac Asimov

Answer :- d

Explanation: The term “robotics” was coined by science fiction writer Isaac Asimov in his 1941 short story “Liar!”. He is also known for the “Three Laws of Robotics.”

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2. Industry 4.0 deals with

a. Cyber Physical Systems that interconnect machines and machines
b. Development of AI
c. Cyber Physical Systems that interconnect machines, humans and AI
d. Brain computer interfacing

Answer :- c

Explanation: Industry 4.0 emphasizes smart automation, where cyber-physical systems, AI, and humans all interact in real-time.

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3. To be called a robot a system should do some or all of the following:

a. Interact with the environment
b. Re-programmable
c. Move around, sense the environment and display intelligent behaviour
d. Follow human’s instructions

Answer :- c

Explanation: A robot is typically a re-programmable, multifunctional system capable of sensing, moving, and acting intelligently in its environment.

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4. The Degree of Freedom of the prismatic and spherical joints are respectively

a. 1 and 3
b. 3 and 1
c. 1 and 2
d. 2 and 1

Answer :- a

Explanation:

• Prismatic joint = 1 DoF (linear motion)
• Spherical joint = 3 DoF (rotation about 3 axes)

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5. A cylinder is kept on a table on its base. How many degrees of freedom are required by a robot to pick up the cylinder and keep it at another place on the table on its base?

a. 2
b. 3
c. 4
d. 5

Answer :- b

Explanation: Robot needs to move in X, Y directions and perform a rotation to maintain the orientation. Hence, 3 DoF.

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6. The work volume of a cartesian robot having four prismatic joints of unequal length is a:

a. Sphere
b. Cube
c. Cuboid
d. Ellipsoid

Answer :- c

Explanation: A Cartesian robot moves in linear axes (X, Y, Z); when the lengths differ, the shape becomes a cuboid.

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7. The position of a point is represented by three coordinates (x, y, z) while orientation of a rigid body is represented by a

a. a position vector and an angle
b. a position vector
c. 4 x 4 matrix
d. 3 x 3 matrix

Answer :- c

Explanation: A 4×4 transformation matrix represents both position and orientation (rotation and translation).

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8. Determinant of a rotation matrix is equal to

a. -1
b. 1
c. 0.5
d. 0

Answer :- b

Explanation: A valid rotation matrix has a determinant of +1. If it’s -1, it’s a reflection.

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9. A frame ‘B’ is rotated by 60° about Z axis of a fixed frame ‘A’. If the coordinate of a point ‘P’ in ‘B’ is given by BP = (1, 1, 1), find its coordinate in frame ‘A’, AP = ?

a. (0.36, 1.36, 1)
b. (-0.36, -1.36, 1)
c. (0.36, -1.36, 1)
d. (-0.36, 1.36, 1)

Answer :- c

Explanation: After rotation of 60° about the Z-axis, transformation gives the coordinates as (0.36, -1.36, 1) (approximated values from cosine and sine calculations).

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10. A frame ‘B’ is rotated by 60° about X axis of a fixed frame ‘A’ and translated by (1,1,1) units in x,y,z direction of ‘A’. If the coordinate of a point BP = (2, 2, 2), find AP?

a. (3, 0.26, 3.73)
b. (3, -0.26, 3.73)
c. (3, 0.26, -3.73)
d. (-3, 0.26, 3.73)

Answer :- b

Explanation: Applying transformation (rotation + translation), you get (3, -0.26, 3.73) after applying the rotated coordinates of the point and then translating.