Creating a 3D plot of a trajectory for multiple robots in formation

I am working with 3 mobile robots that form a triangle. they start at arbitrary initial conditions then form. I want to create a 3-D plot of how the robot positions change time. In a sense that I want to plot their formation at each time step t. For now i can plot robot final positions. see the figure and code snippet. Please advise on how to create this 3-D plot.

oend=length(t1); plot(real(robot1),imag(robot1),'-b',real(robot2),imag(robot2),'-g',... real(robot3),imag(robot3),'-r'), hold on plot(real(robot1(oend)),imag(robot1(oend)),'*',real(robot2(oend)),imag(robot2(oend)),'*',... real(robot3(oend)),imag(robot3(oend)),'*'), z=[robot1(oend) robot2(oend) robot3(oend) robot1(oend)]; plot(real(z),imag(z)), hold off