Questions tagged [kinematics]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
4
votes
0answers
1k views

How to calculate the coupler length in a crank rocker mechanism

I'm trying to learn a bit about building kinematic mechanisms by building a small project. The goal is to be able to open and close a box programmatically via a servo motor. I have a small box that ...
4
votes
1answer
424 views

4 Gears in a Circular Pattern - Calculating the Proper Distances for Meshing

I have recently been working on a gearbox for a robot. I have this pattern of 4 gears with each gear connected to its 2 neighbors. It looks like this: You will probably notice something though. ...
2
votes
1answer
114 views

Bending Moment Doubt

I don't understand how bending moment is being calculated in the problem mentioned in the above link. I understand the parts after that i.e. calculating elastic potential and partial derivatives but I ...
1
vote
2answers
2k views

What is meant by "shock load" in gears?

What is meant by shock load in gears? What are steady, light, medium and heavy shock loads?
0
votes
0answers
54 views

No. Of Instantaneous centres

I’m reading “Theory of Machines and Mechanisms” by Joseph Shigley. Page No. 118 - The author states that A mechanism has as many instant centres as there are ways of pairing the link numbers. Thus,...
3
votes
0answers
53 views

Rotating four cylinders with one motor/actuator

I have a setup with 4 cylinders placed next to each other in following configuration. The cylinders are made of .2mm stainless steel. I would ideally want to rotate them along their axis using a ...
1
vote
1answer
75 views

Unachievable motions because of singular Jacobian

This is the Jacobian of a robot arm (IBB IRB 120) with already specified joint angles (0,0,0,0,0,0). This Jacobian is singular for this configuration. ...
1
vote
0answers
371 views

Inverse kinematics solutions pros and cons

I know at least 3 different approaches to solve inverse kinematics problem. They are pseudo inverse jacobian, cyclic coordinate descent and ANFIS networks. I would like to know advantages and ...
1
vote
3answers
157 views

Compound gear system: Finding velocity

In the figure below we have that the gear $A$ is has an fixed axis and has the radius of $R_a = 0,1m$ and, in the instant represented in the figure spins clock-wise with angular velocity $\omega_a = 4\...
3
votes
2answers
194 views

Rotational Motion Kinematics - Not sure how to fix axis of rotation

Hi I am trying to make a CAD model of something like the scoop sampler shown below. http://www.rolls-royce.com/~/media/Files/R/Rolls-Royce/documents/customers/nuclear/scoop-sampling-tcm92-50918.pdf ...
2
votes
0answers
925 views

Forward and Inverse Kinematics of PUMA 560

I am currently coding a Forward and Inverse Kinematics solver for a PUMA 560 robot. For the Inverse Kinematics part I am using the closed for solution given in this paper. But my issue is, my solution ...
1
vote
0answers
99 views

force transmission in kinematic chain

In the following kinematic chain, I would like to get equation to go from $F_{in}$ to $T_{out}$. (excuse the poor drawing, nodes 3,4,5 are always aligned) Here's my attempt : The torque at $1$ is : $...
3
votes
2answers
222 views

Universal joint vs Double Universal Joint (CV configuration) kinematics

Concerning this subject, I consulted the following Wikipedia page: Universal joint where the elementary kinematics equation of the U-joint is stated. But, a little bit further in the article Double ...
0
votes
1answer
173 views

Kinematics Mechanics Find the length of the belt and the speed of the rack

For A. I know that the formula for belt is simply $L=\frac{Pi(D_a+D_b)}{2}+2C+\frac{(D_b-D_a)^2}{4C}$ Which gives me $L= 116.99"$ since C is equal to $50$ For B. However I'm stuck and can't get the ...
3
votes
0answers
38 views

Parameter effects on kinetics of esterification for bio-diesel production

I want to discuss the effect of parameters on the kinetics of esterification for bio-diesel production. In esterification process, temperature effect and molar ration are two important parameters. ...
2
votes
1answer
989 views

Deformation gradient, strain tensor from cylindrical coordinates

I do not have any engineering background but I am studying some mathematics to try and understand and solve this problem. I have a mesh (M1) in cylindrical coordinates and this deforms into a mesh (M2)...
3
votes
2answers
168 views

Questions on machinery terminology

I have some questions in the basics of machinery terminology Can a spring ever be a link? Most books (eg. Ham et al. 58, Shigley pg. 5) consider links to be rigid. However, I have come across ...
3
votes
2answers
147 views

How to interpete the formula: $I_{G}\alpha = \dot{\vec{H}}$?

I am having hard time to fully undestand what those formula's actually mean. I know the meaning of each element: I : moment of inertia H : angular momentum $\alpha$: angular acceleration $\omega$: ...
5
votes
2answers
10k views

Calculating torque needed to climb a graded hill

I've been designing an electric skateboard which is driven by only one of the rear wheels (for the moment). As I was picking out motors for the board, I soon realized I would need to find a balance ...
5
votes
2answers
459 views

How to calculate the velocity of a piston-like linkage?

I ve tried to solve this problem in so many ways but still didn't manage to do it... What would be the correct way to solve it please? This arm of this mechanism has a length of 0,2m. The piston has ...
3
votes
1answer
102 views

Why do 2 points on a mechanism not have the same angular velocities?

Could someone please explain me why the velocity of point P and P' aren't the same? Appearently it is because the angular velocity of point A and B aren't the same. We are only given that the angular ...
2
votes
2answers
6k views

How do you find the kinematic degrees of freedom of a mechanism?

In the above mechanism it is required to find the generalized coordinates to write equation of motion of the MDOF system. I just want to ask how do we actually approach such a problem? How to identify ...
6
votes
2answers
3k views

Feedback control of two-link planar manipulator

TL;DR: how can I calculate the disturbance at each joint due to coupling forces in a two-link planar robot manipulator actuated by two independent DC motors? I'm studying control theory and trying to ...
1
vote
0answers
113 views

How can a piece of steel rotated without any power input? [closed]

Currently I am trying to rotate a piece of steel >90 degrees without any power input. The piece of steel is attached on the wall. A servo is also attached on the steel. This question addresses ...
1
vote
1answer
683 views

What are the basic mechanism, components or parts to generate relative movements?

I'm an engineer in industrial design and despite that I studied mechanics, kinematics and dynamics, I got difficulties when I try to label or find components which could enable my designs have ...
5
votes
2answers
2k views

Applications of Five-Bar Mechanisms

I have some university work to do based on a real world application with five or six bar mechanism, but I am unable to find such a device. Are there real applications of such mechanisms? I've ...
2
votes
0answers
101 views

Mechanical device to simulate hinge axis external/off of part

Take a horizontal bar 10' pinned on the right end, so that there is a hinge point on the right end. Space requirements dictate that the bar must be cut in down to 5' (cut in middle and keep the left ...
4
votes
1answer
13k views

GIM Mechanism Software (Kinematics / Analysis / Synthesis)

I've recently discovered a very awesome software tool for the synthesis and analysis of mechanisms. The tool is called GIM, from Faculty of Engineering in Bilbao, Department of Mechanical Engineering,...
1
vote
1answer
286 views

4 bar mechanism how does this 4 point method work

I'm wondering if somebody could explain the 4 position method a bit more understandably. I am trying to follow the explanation in here. What I fail to understand is how does the actual fourbar linkage ...

1
2