Science topic

# Kinematics - Science topic

Explore the latest questions and answers in Kinematics, and find Kinematics experts.

Questions related to Kinematics

Gait analysis force calculation at the joints

Till now, I have only processed

**single baseline**(One base - one rover) in RTKLIB in Kinematic or DGNSS mode. Can I process**multiple baselines**(e.g. One base - two rover) in RTKLIB? If so how can I do that?How can I process the raw kinematic biomechanics data? For example, how can I process the C3D files exported from VICON to obtain usable, accurate kinematic and kinetic data? Do you have any book recommendations?

I am new to the subject, thank you all!

I'm planning to do a study on the kinematics of rigid bodies. But I don't know a program where I can draw the shapes that I intend to use in this study.

Dear RG members,

I am working on finding the links between joint kinematic and EMG time series in pathological gait cycles.

The objective is to try to explain altered kinematics from altered EMG.

Do you know of any methodologies to explore that?

Do you think I need a healthy group to study the differences in kinematics and EMG?

Thank you very much for your responses.

Kind regards,

FrEd

Hello

Can I ask for a raw data for normal Gait Kinematics and kinetics that can be added to Excel sheet ?

Thanks in advance, your cooperation is highly appreciated.

Hello Everyone, I am working on 3 DOF parallel manipulator.

I was trying to find the reachable workspace of my parallel manipulator by the Monte Carlo method, and I am facing an error to solve it.

I created a MATLAB script to find workspace by Monte Carlo Simulation Method, the output of the script generates random position coordinates which the centroid of the end effector can reach with at least one orientation.

After generating random coordinates, I was easily able to solve the inverse kinematics by selecting a random coordinate generated by Monte Carlo, but when I tried to solve the forward kinematics, I was not able to get the same position coordinates that I used to solve the inverse kinematics.

Also, when I tried to manually change the leg lengths of my parallel robot in SolidWorks according to the output of inverse kinematics, I was not getting the same position coordinates of the end effector, as the values, I used to solve the inverse kinematics.

Note:

(For Inverse Kinematics Input: randomly generated position coordinate; Output: leg lengths)

(For Forward Kinematics Input: leg lengths obtained from inverse solution; Output: position coordinate of end effector)

I don't know where I am going wrong, Can anyone please help me with this?

Thank you in advance, I really appreciate your help !!

Shiv

I have a set of joint kinematics, collected via 3D mocap. I do not have any corresponding GRF/GRM data. Is there a way to calculate the GRF/GRMs from the kinematic data? I've seen some published work doing this, but the math is a bit above my head. Has anyone published any code etc in which you can plug in some kinematic data and it auto-generates the GRF/GRM for you? Alternatively - can anyone please advise an easy to follow method to calculate GRFs?

Thanks in advance!

Dear all ,

I wanted to ask with an example , let us say , we modeling a CT specimen with XFEM , I wanted to ask what is the difference of specifying kinematic coupling between the pins and hole and giving say displacement (as in displacement control) to the pins to giving displacement to the nodes at the hole directly ? What is the difference between both the cases ?

Is there any mathematical way/method to calculate GRF from kinematic data?

We want to build a reach task with as few elements as possible...

We have a nice workshop and also a 3D printer

Error : The ratio of deformation speed to wave speed exceeds 1.0000 in at least one element. This usually indicates an error with the model definition. Additional diagnostic information may be found in the message file.

Abaqus/Explicit Analysis exited with an error - Please see the status file for possible error messages if the file exists.

Warnings: The option *boundary,type=displacement has been used; check status file between steps for warnings on any jumps prescribed across the steps in displacement values of translational dof. For rotational dof make sure that there are no such jumps. All jumps in displacements across steps are ignored

There are 42 warning messages in the data (.dat) file. Please check the data file for possible errors in the input file.

Boundary conditions are defined at the nodes contained in node set WarnNodeBcIntersectKinCon. In addition the nodes are also part of a surface involved in kinematic contact. The kinematic contact constraint will be overridden by the boundary conditions in case of a conflict. Penalty contact may be used instead.

The nodes in node set WarnNodeCnsIntersectKinC are part of a kinematic contact surface definition as well as participate in a kinematic constraint (or distributing coupling). Nodes that participate in a kinematic constraint definition should not be used in a kinematic contact surface definition. If a degree-of-freedom participates in both types of constraints, the kinematic contact constraint will most often override the kinematic constraint. Abaqus/Explicit will not prevent the user from defining these conditions, but the resul

The ratio of deformation speed to wave speed in the elements in element set WarnElemDeformRateExceedsRatio-Step1 exceed the warning ratio. Refer to the status file for further details. This message is printed during the first applicable increment, but will not be printed during subsequent increments for the remainder of the step.

I have exported an Abaqus model as a .bdf file and then opened it in Nastran. Beams, bushings and kinematic couplings that I had defined in the Abaqus model did not get translated into Nastran. All other details, mesh, boundary conditions, loads, step definitions were translated.

Is there anyway I can translate these 1D elements as well.

I have collected oriented samples of deformed dykes (bearing schistosity and c/s structures, etc).
I have sawn three slabs of each sample orthogonal to each other (xy, xz, and zy planes).
On each slab I should be able to measure the movements (sense of slip).
Now, I would like to have the resulting three main kinematic axes for this sample.
I guess that one way is to draw, on a stereogram, the three planes and their sense of slip and then let the software compute the main axes.
Is this correct? I commonly use Faultkin and Stereonet."

I am looking for study materials about Kinematic chains. Any book or course notes that addresses basic principles and more would be of great help. Thank you!

I'm working with a motion capture system which tracks body markers during walking. This system assignes zero value to markers displacement when it couldn't track them (i.e zero to missing value like figure rawdats).

when I used fourth order zero lag butterworth filter for smoothing, the regions of interest and some parts of the signal changed

I tried converting all zeros to nans (figure nans)and then interpolating the signal but this doesn't work because at the beginng of the aquistion signal is nan which makes the result signal messed.

How can I fill these missing data (interpolate signal with missing data) or smoothing the signal without losing regions of interest

I need the basics for including energy loss in Hamilton formulation for Finite element analysis for vibration of viscoelastic materials. The papers I read use complex modulus to represent viscoelastic losses or convolution integrals. Can someone give me a link where the formulation starts from Hamilton's principle?

I am working on a goalkeeper goalkeeper research which is developing the kinetic response speed of a goalkeeper goalkeeper and I need a standardized test that measures this trait or maybe an electronic device that measures the same trait

Assume this as a beam with a horizontal force acting on top of it. The structure is hinged to a fixed plate with springs on both sides. How do I calculate the forces F2 and F3 based on the known F1 values?

I am doing thermomehcanical analysis for "Short fiber reinforced plastic" based on the isotropic hardening . As i am doing only the isotropic hardening , i want to ask you

a) which hardening effects more on the results either isotropic hardneing or kinematic harening ?

b) How much isotropic hardening effects (for example in %) and how much kinematic hardening contribute in the result and which one is more important.?

I am simulating a sheet metal forming process (Deformable Vs Deformable). Incorporating anisotropic elastic properties would need 21 constants. To make simulation easier, can isotropic elastic constants be used with Hill's yield criteria and kinematic hardening to mimick anisotropy and cold working?

Note: 3D FEA model

I know it is a very basic question but we have tried many times and are getting different values so for the confirmation I am posting here.

F is the Faraday constant (96,485 C mol-1 ). C0 is the bulk concentration of O2 (1.2 × 10-6 mol cm-3 ). D0 is the diffusion coefficient of O2 in 0.1 M KOH (1.9 × 10-5 cm2 s -1 ). ν is the kinematic viscosity of the electrolyte (0.01 cm2 s -1 ). k is the electron transfer rate constant and adopts 0.2 when ω is expressed in rpm.)

To develop constitutive models in continuum mechanics, one must consider kinematics, balance of momentum, balance of energy, and free-energy imbalance. Next, one must propose constitutive response functions that express dependent variables (e.g., free energy, stress, entropy, flux, and chemical potential) as functions of independent variables (e.g., deformation gradient, temperature, temperature gradient, and concentration of species). So, what are the general principles to determine which variables are dependent variables and which are independent variables?

I am confused with co-efficient of friction and friction factor.

A part of a Fluid Mechanics text book says that in Darcy-Weisbach equation

h

_{f}=(f L V^{2})/(2g D)f is friction factor.

In the same time, it says that in below equation the f is co-efficient of fraction.

h

_{f}=(4f L V^{2})/(2g D).In this case, we see that (Friction factor = 4 x co-efficient of friction).

INS-RTK modules claim to be close to a cm accuracy, has anyone used one and if so, how expensive can the telematic charges be if I have a case to run it 18h per day?

What is the best platform for implementing inverse kinematics of a 6-axis robotic arm? I have a robot parts with Nanotec controllers. But there is a lack of information or literature how to control the Nanotec controllers. I'm not an expert in robotics. The task is a part of a project. So it will be good if there are already existing solutions, as there is no reason in reinventing a bicycle.

I would need kinematic data related to the full arm (and not focused on the hand, such as NinaPro dataset). Thanks to anyone who can help me!

I would like to linearize my nonlinear MIMO system (I use this model for reference tracking purposes), but it doesn't fulfill the requirement of feedback linearization. Are there any alternative methods to linearize this system?

I am doing frequency analysis of an orthotropic bridge. To connect the girder with girder, floor beams and edge beams, I assigned MPC constraints to the respective nodes. But after running the analysis, I am getting the following error:

"22 nodes are missing degree of freedoms. The MPC/Equation/kinematic coupling constraints can not be formed. The nodes have been identified in node set ErrNodeMissingDofConstrDef."

I checked again the constraints, but there was not any node with missing dof.

Anyone can suggest me solution? It will be appreciated.

The Coriolis matrix S(q,q') in the Lagrangian formulation is a coupled n*1 matrix. But in many mathematical models, an n*n Coriolis matrix S(q,q') multiplied by q' is used. I need to understand how to transform the former into later. Also, are the q and q' values in the matrix, the desired values, or the instantaneous values?

A kinematic equation that is asking for (1) What could be the highest height the solid object can reach. (2) How long does it take for the object to reach the ground. With the application of Calculus.

I am searching the web for "Thrustpack" modeling software but haven't come across it. Is it open access? Are there any alternative open-access codes for forward kinematic modeling of thrust belts?

What is the principle of RTK (Real Time Kinematic) in the using GPS in topographic and bathymetric survey?

It is a Kinematics in one dimensional motion. Asking for average velocity in meter per second squared and in multiples of gravity which is 9.80m/s².

I have a robotic system that is not actuated in one joint (no torque is applied) and actuated in all other joints.

In this model, the blue rectangles are the links of the robot, the filled small circles are the joints and the circle slot is a constraint that the slider is rotating around it. The red filled circle and the red slot are connected to the ground but the red filled circle is a motor that produces torque. Among other joints, 2 of them are actuated and one is just a joint and isn't actuated.

The slider is applying force to the circular slot to remain on the track. This constraint force consists of a force toward the center of the slot and a moment in the direction perpendicular to the figure.

I want to solve the forward dynamics (by having the joint torques, I want to obtain all link's angular accelerations) to convert it into a state-space form. It is preferable for me to be able to obtain the constraint forces in the slider, also. I don't want to use ordinary newton's method. What other methods do you recommend me to use and why? Please remember that this system is a closed-lop kinematic chain and not a tree-structure (serial kinematic structure). I will be grateful if you introduce good references for the method you recommend.

Thanks

Dear motion analysis experts

I have some motion data that contain double support jumping kinematics.

at the time that I took the test, I didn't know that I have to use 1 force plates for each leg. so my cases jumped on a force plate with both foots.

I used vicon software to calculate kinetic data for demonstrated side.

Is it logical?

if not, what should I do to calculate joints kinetic?

Hi guys! I am recently reading

*Nonlinear Solid Mechanics A Continuum Approach for Engineering by Gerhard A. Holzapfel, Chapter 2.3*and was confused with one equation. You can refer to this stackexchange link for more detail (https://physics.stackexchange.com/questions/558789/why-the-material-time-derivative-of-a-material-field-f-equals-to-the-direction). In short, this equation states that the the material time derivative of a material field 𝐹 equals to the directional derivative of 𝐹 in the direction of the velocity vector 𝑣. I tried to prove this equation but failed and the process has been attached in the stackexchange post. Can someone help me with this?I want to convert the Young's modulus and Poisson ratio of an orthotropic material given in Cartesian coordinates into cylindrical coordinates. Please suggest me the way or provide me the link or document where I can get these things. Thanks in advance

I have been contacted by a famous French journalist who wants to interview me for a French radio program (on Sud Radio) about my preprint on the Mamoudou Gassama affair:

Preprint The Mamoudou Gassama Affair

Since no scientific journal would accept to publish my preprint because of the political dimension of the affair (involving French President Emmanuel Macron), the journalist would like to find scientists, not closely related to me, who would accept to testify that my analysis is scientifically sound. He is not asking for people to testify that what I suggest is really what happened, but just to testify that my analysis makes sense.

Let me know if you are interested, and I will send you the contact information for sending your testimony.

Hi everyone,

I'm trying to setting up a soil property in ANSYS 19.2 student version. I want it to be a Mohr-Coulomb model. But I also want to add a kinematic hardening law to it so that it can caputure the volume change better under cyclic loading.

However, as far as I know, the 'Bilinear Kinematic Hardening' and 'Multilinear Kinematic Hardening' options in 'Engineering Data' are for the metal properties and don't allow any parameter input for the soil kinematic hardening law.

Can anyone help me out?

five-axis industrial robot is being designed for pick and place application. for analysis it i am in need of references

The bionic car which is a concept car is said have an good aerodynamic shape. It having a larger frontal area is cited as a reason.

I am getting higher natural frequency value of a sandwich plate when computed on the basis of HSDT as compared to that of FSDT. But in general it is expected that the higher order kinematics (cubic in-plane displacement) should give lower frequency values than that computed using first order kinematics (linear displacement). I know that my result is correct, but I am unable to justify this point. kindly help

I am looking for EMG signals from any trunk muscle specially obtained for fatigue analysis. Isometric contraction.

I am a bio-mechanic engineer and I want to analyze human different movements like gait and jump.

I had written a code based on Christopher L Vaughan book: dynamic of human gait.

It was good because of calculation of instant center of rotation in joints and it was complicated due to this advantage.

Is there any other useful and detailed reference for calculating joint forces and moments?

I am using optitrack motion capture system to calculate the Maximum Lyapunov exponent from kinematic gait data .Different retro reflective markers are placed on trunk and feet of the subjects.

I m looking for the tool to synthesize the kinematic mechanisms automatically?

A mechanism is moving in a particular pattern. There is a real time video of the same with red color markers are stick to each links. Is there any image processing tool or software which can capture the movement of links and give its change in position, velocity and acceleration? So that the results can be used to co relate rigid body/ multibody dynamic model results.

In the framework of gravitoelectromagnetism (GEM), a gravitational field is a dual entity always having a “field” component

**, and an “induction” component***Eg***simultaneously created by their common sources: time-variable masses and mass flows. By the introduction of the physical quantity***Bg***the description of gravity in GEM takes the kinematics of the gravitating objects into account what implies that GEM is an extension of the classical field theory of gravity.***Bg*In GEM, the phenomenon of the deflection of a light ray passing the sun is explained by the effect of the sun’s gravitational field on the constituent elements of light.

The constituent elements of light, the photons, are moving with velocity

**. According to the “force law of GEM”, a photon moving in a gravitational field (***c***,***Eg***) in general - and in the gravitational field of the sun in particular - will be accelerated with an amount:***Bg***=***a***+ (***Eg***x***c***). The normal component of***Bg***causes the bending of the photon’s trajectory.***a*- At an arbitrary point
*P*near the sun, the vectoris directed to the center of the sun.**Eg** - The direction of the vector (
x*c*) at*Bg**P*depends on the direction of(this is the direction in which the light propagates). If a light ray is passing the sun on one side the direction of*c*is opposite to the direction of the moving surface of the sun (retrograde), and if a ray is passing the sun on the opposite side the direction of*c*is the same as the direction of the sun’s moving surface (prograde). In the first case (*c*x*c*) is directed to the sun, in the second case it is directed away from the sun.*Bg*

So, in the first case the bending effect of

**on the light ray is strengthened by the effect of (***Eg***x***c***), in the second case it is weakened. If half of the observed deflection of a light ray at one side (first case, retrograde) is the effect of***Bg***, the deflection of a ray at the other side (second case, prograde) should be negligible.***Eg**Do this correspond to the observations?*In the above we were looking to the impact on a light ray of the gravitomagnetic effect of the

*rotation of the sun**around its axis*. Another source of the sun’s gravitomagnetic induction is its*translation*. Indeed because the sun, relative to the earth, is moving in the ecliptic with a velocity*it generates a gravitomagnetic field. When***v***is the gravitational field at a point***Eg***P,*it can be shown that the gravitational induction at that point due to the sun's translation can be expressed as:*=***Bg***1/c*.(^{2}*x***v***). Note that, also in this case, the orientation relative to***Eg***of the component (***Eg***x***c***) of the acceleration***Bg***of a photon passing near the sun, is different depending on the side of the sun where the photon passes. Note also that the component (***a***x***c***) =***Bg***x (***e**_{c}*x***v/**c*) is very small relative to the component***Eg***[because of the factor (***Eg***/***v***c*)]**.**Hi!

I'm trying to approach the inverse kinematics of a robot arm with a non-spherical wrist as an optimization problem, as a closed-form solution is extremely hard(or sometimes impossible) to find for such arms.

Most of the articles I've read use the cartesian distance between the current effector position and the goal position as the function to optimize, and constrain the orientation of the effector to the desired orientation to take care of the angles.

However, I'm not quite sure I understand HOW to constrain that orientation and add that constraint to the optimization problem? The way I've formulated the problem is as follows:

1. The function to optimize takes as input the 6 angles for the robot joints

2. The function computes the current pose using the input angles and forward kinematics

3. The cartesian distance is computed and used as the value to optimize

Thank you!

Hi, I´m Mike, and I´m working on a similar project, this is about a discrete PID control for a Stewart-Gough platform and the method that was chosen will make the robot more precise, using inverse and forward kinematics. First of all thanks.

**Background**

I am working on motion capture data analysis of human walking movement. My goal is to find the variation of markers on different body part in relation to the movement of the main body.

For that I am considering upper trunk body and lower trunk body. Upper trunk body include shoulder, chest and upper abdomen. Lower body includes waist , hip ,lower back and lower abdomen.

I have markers placed in each body location. I want to create a marker that represents just the body movement and not the surface variations and joint variations so that it can be used as a surface to create reference variation. For that purpose, I am trying to create a kinematic model

**Problem**

How do I create my virtual point with respect to let's say 3 markers on the upper body? Which motion analysis software can give me this functionality to create some sort of kinematic model.

- let's say create a vector with respect to a plane made by 3 markers and then create a point from the vector with respect to the plane created by the markers.

The attached picture represents my problem for some rough visualization. Here 2 upper green markers are used to create a vector in red which is used to create a green virtual marker.

Hi to every one,

I am trying to model Cold form steel sections in Abaqus using S4R shell elements. Now the sections need to be connected together at the joints by pinned connections.

I'm using an MPC truss constraint between two nodes near the center. My questions are:

- Can you use the MPC in this way for a pinned connection? I have constrained only two nodes from the mesh. One on the master and the other on the slave.
- Do I need to kinematic couple a region of nodes to a reference point (RP) for each surface, and then use the MPC on the master surface RP and slave RP.
- MPC pinned constraint only constrains translation, but I need to release only one rotation for a bracing type of connection.

Thank you,

Allan

I am familiar with an understand the standard approach to deriving the kinematic relationships in a moving frame of reference (e.g. Kane and Levinson). I am having some difficulty, however, with Jazar's derivations within his

*specific*frame-referenced approach[1]. The questions are reference specific (the referenced author uses the same framework across multiple texts).My specific issues are detailed in the attached PDF document (this text editor is a bit limited in regards to presenting formulas). In brief:

- Frame referenced time derivatives v. simple time derivatives of the direction cosine matrix (DCM).
- The frame referenced first time derivative of a position vector expressed in a different frame v. the standard non-frame referenced time derivative of the same.
- The frame referenced first time derivative (G derivative as an example of the frame reference) of the multiplicative term consisting of the DCM (from frame B to frame G) and position vector (in frame B) that appears to drop a term/set it equal to zero in a product rule expansion of the derivative operation.
- Algebraic mapping of the DCM across multiplicative terms.

For each question, I have used selected excerpts from the reference, defined terms and shown the details of the 'work' that explain the question. Any help would be greatly appreciated.

References:

- Jazar, RN (2011) Advanced dynamics: rigid body, multibody and aerospace applications. Hoboken, New Jersey: John Wiley & Sons, Inc.

I am generating a workspace for a 7 degrees of freedom robotic arm using the values in the table below, however according to the code I have written below the x and y ranges obtained do not seem accurate since the diagram indicates that the effector is able to move 1000mm in either direction in the x and y axes - this is incorrect since the end effector can only move approximately 200mm in either direction in the x and y axes.

DH Parameters for 7DOF robot

I have implemented the Monte Carlo method of generating the workspace, however I'm not sure if this is the correct method that I should be using. Are there alternative methods to calculate the kinematics of a robot?

Any help you could provide me would be greatly appreciated!

a1 = 0;

a2_0 = 0;

a2_1 = 40.09;

a2_2 = 144.54;

a2_3 = 182.62;

a2_4 = 516;

a2_5 = 96;

a3_0 = 40.09;

a3_1 = 40.09;

a4 = 0;

a5 = 0;

a6 = 0.91;

a7 = 0.91;

alph1 = pi/2;

alph2_0 = -pi/2;

alph2_1 = 0;

alph2_2 = 0;

alph2_3 = 0;

alph2_4 = 0;

alph2_5 = 0;

alph3_0 = -pi/2;

alph3_1 = -pi/2;

alph4 = 0;

alph5 = pi/2;

alph6 = -pi/2;

alph7 = -pi/2;

alpha1_min = -1.4835298642 + pi/2;

alpha1_max = 1.4835298642 + pi/2;

alpha2_0_min = -0.75049157836 - pi/2;

alpha2_0_max = 0.80285145592 - pi/2;

alpha2_1_min = pi/2;

alpha2_1_max = pi/2;

alpha2_2_min = 0.75049157836 + pi/2;

alpha2_2_max = -0.80285145592 + pi/2;

alpha2_3_min = 0.75049157836 + pi/2;

alpha2_3_max = -0.80285145592 + pi/2;

alpha2_4_min = -0.75049157836;

alpha2_4_max = 0.80285145592;

alpha2_5_min = -0.75049157836 + pi;

alpha2_5_max = 0.80285145592 + pi;

alpha3_0_min = 0;

alpha3_0_max = 0;

alpha3_1_min = 0;

alpha3_1_max = 0;

alpha4_min = -1.5009831567;

alpha4_max = 1.5009831567;

alpha5_min = -1.3962634016 + pi/2;

alpha5_max = 1.3962634016 + pi/2;

alpha6_min = -1.5009831567 + pi/2;

alpha6_max = 1.5009831567 + pi/2;

alpha7_min = -1.5009831567 + pi/2;

alpha7_max = 1.5009831567 + pi/2;

d1 = 0;

d2_0 = 0;

d2_1 = 0;

d2_2 = 0;

d2_3 = 0;

d2_4 = 0;

d2_5 = 0;

d3_0 = 0.0012217304764 - 431.8 + 144.54;

d3_1 = 0.0012217304764;

d4 = 416.2;

d5 = 0;

d6 = 0;

d7 = 0;

N = 20000;

t1 = alpha1_max + (alpha1_max - alpha1_min)*rand(N,1);

t2_0 = alpha2_0_max + (alpha2_0_max - alpha2_0_min)*rand(N,1);

t2_1 = alpha2_1_max + (alpha2_1_max - alpha2_1_min)*rand(N,1);

t2_2 = alpha2_2_max + (alpha2_2_max - alpha2_2_min)*rand(N,1);

t2_3 = alpha2_3_max + (alpha2_3_max - alpha2_3_min)*rand(N,1);

t2_4 = alpha2_4_max + (alpha2_4_max - alpha2_4_min)*rand(N,1);

t2_5 = alpha2_5_max + (alpha2_5_max - alpha2_5_min)*rand(N,1);

t3_0 = alpha3_0_max + (alpha3_0_max - alpha3_0_min)*rand(N,1);

t3_1 = alpha3_1_max + (alpha3_1_max - alpha3_1_min)*rand(N,1);

t4 = alpha4_max + (alpha4_max - alpha4_min)*rand(N,1);

t5 = alpha5_max + (alpha5_max - alpha5_min)*rand(N,1);

t6 = alpha6_max + (alpha6_max - alpha6_min)*rand(N,1);

t7 = alpha7_max + (alpha7_max - alpha7_min)*rand(N,1);

for i = 1:N

A1 = TransMat(a1,alph1,d1,t1(i));

A2_0 = TransMat(a2_0,alph2_0,d2_0,t2_0(i));

A2_1 = TransMat(a2_1,alph2_1,d2_1,t2_1(i));

A2_2 = TransMat(a2_2,alph2_2,d2_2,t2_2(i));

A2_3 = TransMat(a2_3,alph2_3,d2_3,t2_3(i));

A2_4 = TransMat(a2_4,alph2_4,d2_4,t2_4(i));

A2_5 = TransMat(a2_5,alph2_5,d2_5,t2_5(i));

A3_0 = TransMat(a3_0,alph3_0,d3_0,t3_0(i));

A3_1 = TransMat(a3_1,alph3_1,d3_1,t3_1(i));

A4 = TransMat(a4,alph4,d4,t4(i));

A5 = TransMat(a5,alph5,d5,t5(i));

A6 = TransMat(a6,alph6,d6,t6(i));

A7 = TransMat(a7,alph7,d7,t7(i));

T = A1 * A2_0 * A2_2 * A2_3 * A2_4 * A2_5 * A3_0 * A3_1 * A4 * A5 * A6 * A7;

X=T(1,4);

Y=T(2,4);

Z=T(3,4);

plot3(X,Y,Z,'.')

hold on;

end

view(3);

title('Isometric view');

xlabel('x (mm)');

ylabel('y (mm)');

zlabel('z (mm) ');

% view(2); % top view

% title(' Top view');

% xlabel('x (mm)');

% ylabel('y (mm)');

% view([0 0 1]); % y-z plane

% title('Side view, Y-Z');

% ylabel('y (mm)');

% zlabel('z (mm)');

function [ T ] = TransMat( a,b,c,d )

T = [ cos(d), -sin(d)*cos(b), sin(d)*sin(b), a*cos(d);

sin(d), cos(d)*cos(b), -cos(d)*sin(b), a*sin(d);

0, sin(b), cos(b), c;

0, 0, 0, 1];

end

Hi everybody,

I want to simulate a bubble moving in fluid, say blood using comsol. For such type of interfaces, to couple mesh motion with fluid motion, dose the following kinematic boundary condition is okay?.

u.n= u*nx+v*ny

or n*(u-xt).

here t is time. which one is correct?. Thanks in advance.

Hi, I am planning a doctoral study using a novel immersive virtual reality playground for children with DCD and TD children, ages 7-10. I was planning on using referred children with DCD but was considering using the DCDQ'07 with the parents of both groups. I am also planning to administer the M-ABC2 for children who have not undergone this evaluation. We will be collecting kinematic data as well as task success, time for task performance and perceived motor competence. Our independent variables include level of immersion, level of output display gain, and setting (a real trampoline in the virtual environment (VE), a virtual trampoline in the VE, and a real trampoline in a real setting.

1.Can you share the full text of this article with me? 2. Would you consider a different tool for this purpose?

Thanks!

Sarina Goldstand

**Are the same repetitive kinematic parameters generated by endodontic motors sufficient for the concept of single-file endodontics?****Do the simplified single-file systems need more complicated kinematics generated by more talented endodontic motors?**

I am looking for forward kinematic of 3_PRR robots

but not numerical or neural solution

I looking for parametric solution

I have done detumbling of a 3U cubesat using Bdot law, magnetometers and magnetotorquers. The magnetic field and dynamics and kinematics have been correctly modelled but one of my angular rates is not getting 0.

I am about to visit wind tunnel facilities to test an automotive vehicle. The speed at which the CFD analysis are being carried out is 17 m/s To avoid the blockage effect a scaled model will be created with a scale of 1:3. I am assuming that in order to achieve the kinematic similarity the Reynolds number must be the same. Hence, the speed must be 3 times greater than the speed of CFD simulations. I have assumed that the forces acting on the car will be given by the equation RealForces =(1/scale^2)*ModelForces.

These forces will be the forces for the real car running at three times the speed?How can I calculate the forces acting on the real car at 17m/s??

I would like to be able to import footage from 2 or more cameras to analyze the motion of mammals. Lmbs is what mainly interests me.

I know of MOKKA and SkillSpector but SkillSpector has been crashing.

Have you got more suggestions?

We can choose one or two back stresses when we set up the nonlinear kinematic/isotropic hardening in ABAQUS. How do we decide the number of back stresses? let say model under uniaxial or multiaxial load.

Thanks,

I am looking for a GPS receiver with a sampling rate greater than 1 Hz. I looked online for Real time kinematics GPS receiver which have higher sampling rate but they are expensive. I am looking for other recommendations

Please see the image attached for the complete question.

I simulated inverse kinematic of ur10 and T01,T12,T23,...

are complex .is it true? I attached symbolic kinematic (mfile) and error.