Computer Aided Engineering Design

380 COMPUTER AIDED ENGINEERING DESIGN

case the cloth cuttings required for stitching the shirt) and then developing the relation between the
geometric parameters required to draw these cutting in terms of the user specified feature dimensions.

Project 4

Develop an algorithm to design generic B-spline curves and surfaces. The Input parameters shall be
the order, number of control points and their co-ordinates. Write functions to calculate the knot
vectors, basis functions and finally the function, for calculating points on a B-spline to display. Also
for a parameter value u on the curve, calculate the position vector, tangent and curvature.

Project 5

Develop algorithms for designing surfaces of revolution and sweep surfaces. The Input parameters
shall be the order, number of control points, their coordinates for the B-spline curve and a vector
defining the axis of revolution or the direction of sweep as the case may be. Use the code developed
in Project 4 to design a B-spline curve to be used as curve to be revolved or swept. For simplicity,
assume the curve to be lying on the XY plane. In case of surface of revolution, the axis of revolution
is the Y-axis and in case of a sweep surface, the direction of sweep is the Z-axis. Also for parameter
values ‘u’ and ‘v’ on the surface, calculate the position vector, tangents and curvatures.

Figure P1. The configuration of the object “Drop” and point P at time t = 0

0

26.5651 deg

A

P B

10.0000 mm

5.0000 mm Path of A

Path of P

z