Skip to main content
6 of 29
deleted 2 characters in body
cvgmt
  • 84.1k
  • 6
  • 97
  • 179

We use FrenetSerretSystem to calculate its tangent vector and normal vector at c[t0].

c[t_] = {t^2, t};
tangent[t_] = FrenetSerretSystem[c[t], t][[2, 1]];
normal[t_] = FrenetSerretSystem[c[t], t][[2, 2]];
s[t_] = ArcLength[c[τ], {τ, 0, t}];
t0 = .5;
Show[ParametricPlot[c[t], {t, 0, 1}], 
 Graphics[{Arrow[{c[t], c[t] + normal[t]}], 
    Arrow[{c[t], c[t] + tangent[t]}]}] /. t -> t0, PlotRange -> All]

enter image description here

And then we calculate the ArcLength of the parametric curve {t^2,t} from 0 to t0 then we get the point {0,s[t0]} in y-axis.

After that we translate {0, s[t0]} - c[t0] and rotate tangent[t0] to the y-axis direction {0,1} so that the new curve tangent to the y-axis at {0,s[t0]}.

c[t_] = {t^2, t};
tangent[t_] = FrenetSerretSystem[c[t], t][[2, 1]];
normal[t_] = FrenetSerretSystem[c[t], t][[2, 2]];
s[t_] = ArcLength[c[τ], {τ, 0, t}];
r[t_, t0_] := 
  RotationTransform[{tangent[t0], {0, 1}}, {0, 
     s[t0]}][(c[t] + {0, s[t0]} - c[t0])];
Manipulate[
 ParametricPlot[r[t, t0], {t, 0, 1}, AspectRatio -> Automatic, 
  PlotRange -> {{0, 1}, {0, 2}}], {t0, 0, 1}]

enter image description here

cvgmt
  • 84.1k
  • 6
  • 97
  • 179