A mechanical linkage is an system of connected bodies. The connections are called joints, that come in many flavors. Linkages allow you to design various path movements, speed profiles and force changes. The simplest possible linkage is a four bar mechanism and its special case the crank mechanism.

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### Is there a formula that relates the two angles in a crank rocker?

I'm working on a mechanism that requires a crank rocker - is there a formula that relates the angle (to some fixed reference; horizontal, vertical, whatever) of the driving "crank" to the ...
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### What would you call this mechanism and how can I calculate the forces involved

So I have an assembly with two pins sliding in two groves. First I would like to know if there's a name for this so I can do some more research. Second, if the assembly is standing up so that the top ...
297 views

### Linkage of two shafts that need to rotate different angles

I have two switches that have different throw angles the switches have shafts coming out of them which are connected the the cams that can be seen in the attached pic. One needs to rotate 95 degrees ...
64 views

### How to generate a repeating semi-circle waveform using a mechanical linkage

How can one, in a smooth way, produce a semicircle wave, as opposed to a sinusoidal wave ? Imagining the machinery and linkages behind the movement. I mean the trace. For example a point fixed in ...
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### 3D linkage design - terminology

I am designing an animatronic head, which has five degrees of freedom: pitch, roll and yaw for the head part, and pitch and yaw for the neck part. However, the yaw movements for the head and neck are ...
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### Linkage between two vertically and horizontally offset wheels

I'm trying to drive a wheel with a radius of 20cm that is 20cm above the motor and horizontally offset by 20cm from the motor, similar to the following: I wonder what a good linkage might be for a ...
213 views

### Rotation around an axis outside of the mechanism

I want to design a system of linkages that will allow me to rotate the green element around the blue point/axis without entering the red circle. The green triangle to go fully around the blue point. I ...
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### Why does this linkage calculate log?

From wikipedia, there's this animated GIF of a linkage. Question: How does it calculate log? All I see there are trig functions and circles. log doesn't show up in ...
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### Toggle position of a fourbar slider-crank

In the fourbar mechanism as in the following picture, I have to find the toggle position, the sliding distance and the time ratio. Here is my understanding/plan to do this: The toggle positions ("...
59 views

I am facing a difficult question and can't find answers anywhere else. What on the left is a hydraulic ram, it's pushing the box in the centre to move upward, while the four-bar linkage attached on ...
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### Is there a spherical joint equivalent to a 4 bar linkage?

In a 4-bar linkage, all the joints are regarded as hinge joints. However, when I searched "spherical 4-bar linkage system", I didn't get a 4-bar system with spherical joints but instead a 4 bar system ...
104 views

### Analytical six-bar linkage trajectory solution

Six-bar linkage is shown on the image: It has one degree of freedom, so if one of the variables is constrained, it's possible to calculate the positions of all the joints. In this specific case the ...
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### 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 ...
174 views

### Calculating force exerted on plate by link

I am currently involved with a project using a mechanism similar to that seen in 'table tilters' and we are struggling to work out how to begin resolving the forces. The image shows the state we are ...
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### What is the correct mathematical approach to this linkage problem?

I have a linear actuator with 52 millimeters of travel. I have a set of linkages with specific dimensions as shown in the images below, to which this actuator will be attached. The REF dimension is ...
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### How to quickly design and simulate crank based mechanisms? [closed]

I'm doing a project on Theo Jansen's Mechanism, where I have to modify the mechanism. What is the most efficient way to design these mechanisms? Is there any good software where I can just draw the ...
453 views

### what college level teaches mechanical linkage design?

I'm 17 years old and learning first-year college math. What college level math do I need for mechanical linkage design? Can I learn designing and creating mechanical linkage without math but with my ...
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### Gear design for symmetrical opening of two parts

I'm trying to build a lamp which has about 20 identical layers stacked on top of each other. There is a central spine and, on each level, a pair of arcs attached to the spine that are hinged and which ...
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### What are a few low-cost options for building linkages?

I'm working on a project trying to combine a pantograph linkage with a four-bar linkage. I'd like to build it out of relatively at-hand materials (AKA, nothing requiring a machine shop), and I'd like ...
357 views

### Synthesis of 5 bar mechanism

I'm working on my university project but I can't find a proper synthesis method for 5 bar mechanism. I'm working on underactuated mechanism. It's a slider crank with the connecting rod divided into 2 ...
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### How to build a pivot linkage for a robot.

I have asked this question in 3DPrinting.stackexchange forum but got no answer answer. Please take a minute to see if you can help. I am building a simple RWD vehicle using 3d printer parts. See the ...
548 views

### How do folding barriers work?

With folding barriers like the one below, how does the orange bar get turned by the green mechanism? What's inside the yellow triangular part? https://www.youtube.com/watch?v=LF8kSTCZIxw
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### Difference between Linkage, Kinematic chain, Mechanism, Mechanical element, Mechanical machine and their precise definitions

Recently I started to study about "Design of mechanical machinery". Since I am a person who is very sensitive about words I want to know the difference between these notions and their precise ...
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### Lengths of Connectors in Steering Linkage

Below is a picture 4-wheel vehicle steering linkage. I figured that in order to steer correctly $(W+D)tan\theta_1=Dtan\theta_2$ where $\theta_1$ is the angle of the outside front wheel, $\theta_2$ is ...
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### Design of a Four-Bar Infinity Coupler Linkage

How can I control a Four-Bar Infinity Coupler such that it does not accidentally become a Paralellogram Linkage? It seems to me that, when the bars are all horizontal, gravity could change the ...
177 views

### How fast can Jansen's linkage driven walker go?

I've seen videos of Theo Jansen's linkage driven walkers, and they all walk really slowly. Is it because they want to showcase leg movement or these things actually can't move fast?
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### What factors into the high cost of transmission components? [closed]

I've been shopping around for gears, pulleys and other transmission components for building a milling machine over the past few weeks. Many of these parts are so rudimentary and ubiquitous, yet the ...
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### 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 ...
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### 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,...