How to plot vectors using quiver3

here is my code i need to plot a,T,B,and N at t=pi on the interval -pi:0.1:pi but i cant get it to work can anybody help me please.

syms t
a=[0.5*cos(t), -sqrt(3)/2*cos(t), 1+sin(t)];
T=diff(a);
Answer1=T
N=diff(T);
Answer2=N
B=simplify(cross(T,N));
Answer3=B
C=cross(T/(sqrt(sum(T.^2)))^3,N/(sqrt(sum(T.^2)))^3);
Answer4=simplify(C)
syms t clear
t=-pi:0.1:pi;
a=[0.5*cos(t), -sqrt(3)/2*cos(t), 1+sin(t)];
T=diff(a);
N=diff(T);
plot3(0.5*cos(t), -sqrt(3)/2*cos(t), 1+sin(t))
hold on
plotT=quiver3(-0.5,0.866025403,0,-sin(pi)/2, (3^(1/2)*sin(pi))/2, 
cos(pi))
plotN=quiver3(0,0,-1,-cos(pi)/2, (3^(1/2)*cos(pi))/2, -sin(pi))
plotB=quiver3(pi,pi,pi,-3^(1/2)/2, -1/2, 0)
hold off

[bym]

you said you need to plot at t = pi, yet then you mention interval of -pi:.1:pi can you clarify?