Recent content by noelll

Hi! Thank you for your reply! Base on my knowledge, i = 2:h:n refers to i starting value 2 will have a increment of h till it reached the value of n . Is this causing me the problems? What would you suggest me to do instead? Sorry to trouble you! Noel

Hi, Thank you so much for your reply, yes the immersed volume of the lifeboat is changing as it enters the water and i would need to evaluate a new volume each sec, when it dives in. However, i tried doing a while loop, and my code just kept running, my knowledge in MATLAB is at beginner's...

Hi there, Homework Statement I am doing a simulation of a free-fall lifeboat trajectory into the ocean and there is a part where i need to get the volume of the lifeboat to obtain its buoyancy force. Buoyancy force is proportional to the immersed volume of the body and this volume can be...

Hi Jason, Thank you so much for your reply, sorry for my bad explanation. Currently I am using this journal paper (attach) to do my coding. Hence, the equations and solving two problem are all base on the equations in the paper. alpha is the angle of launch and by using the equations in the...

Hi Twigg and Jason, thank you so much for your reply. I took Jason advise and i re-do my RK algorithm. clc; % Clears the screen clear all; % Constants g = 9.81; degree=55; alpha=(degree*(pi/180)); M = 6000; fr = 0.05; Bx1 = 1.95; Bx2 =...

Hi Twigg, Thank you so much for your reply, I am currently following a journal paper(attached) base on the paper during rotation phase ##\Phi''## and ##\omega(t)## should constantly change with time. I am not sure if the problem due to my runge kutta algorithm. Therefore, i am not absolutely...

Hi Twigg, Thank you so much for your reply, yes i went to check and phi is changing by very small step, i also check my coefficients and the value i get is correct. Could it be my runge kutta algorithm were wrong? Because base on the motion equations i shared above, equations does not have any...

Hi thank for your reply, Yes my phi and omega did not change it still remain the same as what i have input as the initial parameters, however but for my X and Z it change according to time. Therefore, I feel that my phi and omega is not passing into the runge kutta loop. Then again my X and Z...

Hi thanks for your reply, tried de-bugging it and the code seems fine, so i was thinking it should be my runge kutta algorithm. I start learning runge kutta just last week and i still do not really understand how the coupled equations work. base on what i did above, was to find the value of...

MX''=Fn(cosΦ−usinΦ) MZ''=Fn(sinΦ+ucosΦ)−Mg MΦ''=Fn(Bxx+uBz) I tried using Runge-Kutta methods to approximate motion equations in MATLAB but it turn out wrong. I also tired finding and researching forums and web for solution but to no avail. Fn,M,θ,u is constant fn/M = 0.866 it seems that i...

Hi thanks for your reply, clc; % Clears the screen clear all; thete=30; g= 9.81; %Constant h=0.001; % step size tfinal = 3; N=ceil(tfinal/h)...

Hi thanks so much for your reply, However my knowledge on MATLAB functions is still limited , base on my four 1st order ode X' = Vx Z' = Vz Vx'=[fn*(sin θ - uCos θ )]/M Vz'={[fn(cos θ + uSin θ )]/M} - g Do I need to write a function for each ode? How do I write it? Currently I only have...

Homework Statement Hi There! MX''=Fn(sin θ - uCos θ ) MZ''=Fn(cos θ + uSin θ ) - Mg Fn,M,θ,u is constant fn/M = 0.866 M = 6000 θ = 30 u = 0.5774 i split my motion equation into 2 individual 1st ode, X' = Vx Z' = Vz Vx'=[fn*(sin θ - uCos θ )]/M Vz'={[fn(cos θ + uSin θ )]/M} - g...

Hi, my name is Noel, i am currently a final year student , in newcastle university majoring in offshore engineering! i love to play dota, going out to watch movies, listening to musics and love reading book. I hope to make many like minded friends through this forums and finally NICE TO MEET YOU!