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Answer the questions which you are most confident in. It is impossible to answer all the questions in

the allotted time. The difficulty increases with the number of stars.

Answer as precisely as possible and restrict your self to simple sentences and points, or one word

answers. Remember, this is for inductions so we need to know what you are good at, and not how well

you write exams.

1.An arm connected with the following joints is shown in the figure. ***

A. Determine the relation between the angle theta1, theta2, theta3,l,m to a specific point in Cartesian

space. (hint: first convert Cartesian co-ordinates to polar form; to find a relation use triangle formula

rather than deducing relations with equations directly) assume initial positions of angles. Draw

diagrams when necessary.

2. The degrees of freedom of a machine is defined as the number of independent parameters required to

locate a configuration of the machine. How will this information(knowledge on the number of degreesof freedom for the robot) help design a robot?

3. Give the best situations for the application of the following drives (under which terrain, speed of

motion, power needed, practicality, also state a phrase for a reason)

A. Biped walking

B. Differential drive with tracks (tanks)

C. Differential drive with castor and independent wheels

D. Car steering drive

4. Static friction is the co-efficient of friction between two surfaces when there is zero relative motion

between the two surfaces. Dynamic friction is the co-efficient of friction between two surfaces when

there is relative motion between the two surfaces. How is this information useful and for which drive

is it suitable? (state your answers in points, and specify which drive will favor and not favor the

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particular type of friction)

5.You are provided with an accelerometer, which gives accelerations in three dimensions.

A. How will you find distance traveled with the readings.

B. How will you find the orientation of the robot,(initial position and orientations are given)?

C. Can orientation be calculated with just one accelerometer? If it cant state the assumptions that arerequired so as to measure the orientation.**

6. The following Gear trains are shown.

A Which gear system will have the greatest ratio between Output Torque/Input Torque(W):

B. Give the ratios between the Ws in each case. (a : b : c)

C. Design a gear train which changes the axis of rotation.

D. Design a gear train which is unidirectional, ie.. does not function when the driver and driven are

interchanged.

E. Design a gear system for a crane which pulls loads up but when it is turned off(power is removed to

the input shaft) does not fall back to the ground. *

(for all the DESIGN questions draw diagrams, for representing gears use circles for front view and

rectangles for side view (as shown in the figure), and write their diameter, adjacent to or inside the

gear., for special types of gears like helical or beveled gears, label them )

7. A. Which type of drive is useful for navigating rough rocky terrain with bumps, front wheel drive, or

rear wheel drive? State a reason.

B. Design a method to climb stairs. (draw a diagram and explain in 5 sentences)

8. Draw 3 sketches depicting a biped moving forward. Draw stick figures. Show the center of gravity

and if necessary show the front view and top view for each sketch. *

9. An arm is shown in the following diagram, which is controlled by a motor, holding a weight at its

other end. Find the minimum torque necessary to just start motion in the arm.

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ALL THE BEST