Surface with Frenet frame

陳隆期 shared this question 5 months ago
Needs Answer

Greetings everyone,

I tried to draw a surface along a curve,by using Frenet curve.

In the file you can see I draw a curve c on plane,

and use unitvector(perpendicularvector(c'(t))) and (0,0,1) as Frenet frame to draw circles at each point to construct a surface named h(t,s),

But you can see that unitvector(perpendicularvector(c'(t))) didn't work well.

In another way, I use curve command to script this circles p(s), it works .

So I want to know how to fix this problem or is this a bug ?

Thank you for taking time to read this.

Comments (2)

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1

try using curves in 3D (ie:third value 0); I see 2D and 3D mixed in your work

then from a' a'' get (a'⊗a'')⊗a' and a'⊗a'' for normal and binormal directions. then unitvector

please, what is the definition of surface you want

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Thank you, it looks better now.

Finally I found the problem is the vector command in surface command have high probability cause error.

So I computed the unit cross vector and put in surface command, it worked finally

I still wanna know if it is a bug or I type the command in a wrong way.

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