MaplePrimes - Questions and Posts tagged with model

DirectSearch optimization package

gilp — Wed, 27 Mar 2013 09:24:38 Z

Hi,

I'm using the DirectSearch package in a 10 periods model and in the first period i get this values:

> DirectSearch[SolveEquations](sys, assume = positive);
Warning, complex or non-numeric value encountered; trying to find a feasible point
        [HFloat(1.1842542076623546e-32), 

          Vector[column](%id = 18446744078126621390), [

          x1a = HFloat(4204.651582462925), 

          x1c = HFloat(4204.651582462925),

Model the Human hand constraining the fingers to a cerain range of angles

Kenna — Sat, 26 Jan 2013 22:58:00 Z

I am new to maplesim. I want to model the human hand and constrain the fingers to a certain range of angle. Then apply a controller to analyse its controllability and also see the dynamic equation formulation

How to plot multiple data points

gdog — Thu, 13 Dec 2012 17:44:47 Z

I am trying to model the change in lifetime versus mass and have the formula;

> T := 6.58*10^38*10^(-25)/x^3;
                                      
> plot(T, x = 10^10, 10^9, 10^8, 10^7, 10^6, 10^5, 10^4, 10^3, 10^2, 10, 10^0);
Error, (in plot) unexpected options: [x = 10000000000, 1000000000, 100000000, 10000000, 1000000, 100000, 10000, 1000, 100, 10, 1]

I want to plot for values between x=10^-11 and 0, i have this error and i am not sure why.

Correlation coefficient for system of nonlinear differential equations and data

kierstejn — Wed, 12 Dec 2012 19:35:44 Z

Hey guys..

I need some help on determining the correlation coefficient between my data points for an Influenza epidemic and the SIR model, with my estimated parameters Beta and Alpha. The initial conditions for the equations are defined at the beginning of my worksheet:

SIR_model.mw

Hope someone can help me ;)

Simulate Cutting a Rope

karishanson22 — Thu, 29 Nov 2012 02:46:09 Z

I have modeled something like a rope attached to a fixed frame at both ends. Is there a way to detach one end of the rope from the fixed frame during a simulation? Is there a better way to go about this? I want to be able to release one end of the rope during the simulation.

Any advice or thoughts will help.

Thanks

Zemax integration with MapleSim

rwong1231 — Fri, 09 Nov 2012 05:28:12 Z

Hi,

I was just curious if MapleSim has integration capability with Zemax.

I'm interested in creating a dynamic electro-mechanical model (i.e. optical imaging on a moving system):

Zemax <--> MapleSim

If there isn't a toolbox yet, is there a workaround?

Thank you again!

modelling of pile foundations

cesar torres — Fri, 26 Oct 2012 10:50:42 Z

I am writing to request some general opinion/support. I’m new to Maple and I’m interested in analysing a pile foundation (long steel pipe driven into the ground). The pile is normally modelled as a series of masses interconnected by straight elements and the soil surrounding the pile is modelled as a series of non-linear springs acting on each of the masses.

I would like to know if this is something that can be done in Maple or if MapleSim is needed.

Phase change

lisa1301 — Wed, 17 Oct 2012 14:37:43 Z

Hi everybody,

Does somebody has an idea about how to model the temperature of water during freezing ?

I mean, if you consider a certain mass of water and you put it, for example on a fridge. I don't consider the convection but only the diffusion, and I would like to model, if possible with an animation the temperature of the water (as a cube for the shape).

Normally, during the freezing I should observe a decrease of the temperature, then a freezing...

Model Spiderweb in MapleSim

karishanson22 — Thu, 04 Oct 2012 20:47:42 Z

I have been messing around with MapleSim for a while now, and I cannot find a good way to model something such as a spiderweb. I want to be able to model a spiderweb (using something like cables), and then measure the tension in the cables, and also vibrations as they travel through the cables. Is this something that I can accomplish using MapleSim? If so, what is the best way to approach this problem? Any suggestions or comments would be helpful. Thanks.

Linear Population Models

Chrissieh18 — Tue, 25 Sep 2012 10:16:47 Z

I am trying to plot a Linear Population Model using Maple, could anybody tell me what I am doing wrong. My plot is just registering as a straight line at 1.0 and I know this is incorrect.

Modelling Flow Inertia in Three Coupled Liquid Tanks

Samir Khan — Thu, 30 Aug 2012 23:42:55 Z

1 Introduction

Three tanks are connected with two pipes. Each tank is initially filled to a different level. A valve in each pipe opens, and the liquid levels gradually reach equilibrium. Here, we model the system in MapleSim (including the influence of flow inertia), and also derive and solve the analytical equations in Maple.

How to choose the best solutions from multiple solutions in inverse kinematics model?

onder — Sat, 25 Aug 2012 21:04:21 Z

Hi,

I have an inverse kinematics model for a double inverted pendulum. There are multiple solutions for each joint angles due to symmetry and I have to choose the appropriate ones. I thought I can use the previous choices and compare them with the current multiple solutions, so I could choose the ones which are closer to the previous ones. However, since the double inverted pendulum moves in in both region at the equilibrium, this aproach does not work. Could you advise...

Error, (in dsolve/numeric/DAE/isolate) is not linear

gpasmit — Fri, 10 Aug 2012 14:57:29 Z

Dear All,

Im trying to model a rigid body, hanging from a string. In the end I have a system of 5 Equations of Motion and with all the Initial conditions I use dsolve. It gives me the error

Error, (in dsolve/numeric/DAE/isolate) is not linear

I know the system is not lnear but that should be not a problem. One strange thing I notice is that Maple adds these dots in some equations: (the one after 15 but please see original file)

15.*cos(`ϕz`(t...

Why cant maplesim solve this model?

JotaTR — Mon, 16 Jul 2012 22:34:09 Z

Hi,

The model that i uploaded (EqQui.msim) has a component with severall output and 4 inputs, but 2 of the inputs (LgKph2o and Lgkpco2) depends on one of the outputs. The 2 interpolation tables transfor the output variable (temperature) in this two inputs. All components works fine independtly (first "model", the one on the top), but if i link the exit of both interpolation tables mapleSim say it cant solve a lot of variables.

How do I solve DAEs given by MapleSim in Maple?

greenjeans97603 — Tue, 26 Jun 2012 19:28:39 Z

If I have a MapleSim file that successfully runs and I want to manipulate the data and equations in Maple, how would I do that? I know how to link a MapleSim file to a Maple document, and how to pull out the system of reduced DAE's, ODE's, parameters, etc. My question is whether or not there's a simple way to have Maple solve those equations and be able to display the same type of data (graphs, export the numerical solution to the system to an Excel file, etc.) that...