Questions tagged [mechanism]
A mechanism is a device designed to transform input forces and movement into a desired set of output forces and the movement.
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How do I motorize the elbow socket and other joints in a powered exo-skeleton?
How would you motorize the joints in an Iron Man suit? You need something fairly shallow, I would think, probably dual servos sitting on either side of an elbow or knee joint or either side of your ...
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Education sources for robot building?
I teach FTC robotics to high school students, and while I'm a proficient programmer and can teach them coding fairly well, my mechanical skills are a bit soft. I'm looking for good sources for myself ...
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SCARA Arm Lead Screw Choices
I'm thinking about building a SCARA Arm to lift moderate loads(5lbs) with a high degree of accuracy. I want a relatively quick and inexpensive Z axis gantry, and I was thinking about using a lead ...
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Can you have a career in robotics if you hate mechanics? [closed]
I'm a first year electronics engineering student. I love almost all the aspects of robotics - the electronics, algorithms, control theory etc. I can't stand the mechanical aspect of robotics though.
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How does the Makeblock threaded slot work?
I've been looking into a Makeblock robotics kit but have found no information on the web that comes from end-users, and one of the main advertised features is not clear to me: The slot threads shown ...
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Plastic shaft supports
I would like to prevent a shaft from being pulled through it's bearings - that is, press a plastic ring around it on either side. What are these rings called? They're not bearings or hubs. And where ...
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Building a non rotating persistence of vision device
I'm looking for a way to create a non-rotating persistence of vision device. I have all the electronics set up but I'm stumped with the mechanical design.
I tried these two designs:
But these didn't ...
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12V compressor and air pressure control
I am trying to make a simple robot with few functionality for someone, one of these functionality is inflating a balloon inside the robot, I know how to control a compressor using Arduino but the ...
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Why linkage-based haptic devices are much more common than cable (tension)-based ones?
According not only to this link, but in my humble opinion to common sense as well, cable-based haptic devices have got lower inertia and are less complicated mechanically. I also believe that ...
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Gears modeling in Google SketchUp and SketchyPhisics
I'm trying to make differential in Google SketchUp using this tutorial http://support.ponoko.com/entries/21249896-Gears-and-Joints-with-SketchUp-Sketchy-Physics for gears modeling.
But I have problem: ...
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Lifting robotic leg with only one servo
Note before I start: I have not actually put anything together yet, i'm still just planning, so any changes that require a shape change or anything like that are accepted.
I'm working on making a ...
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How can this mobile robot rotate so perfectly?
Please have a look at this youtube video.
When this mobile robot operates, the rack (which is said to weight up to 450 kg) can have its Center Of Mass (COM) distributed at any location. For example, ...
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How to measure and dispense a finite amount of powder or liquid
I've been watching too much How It's Made, and I've been wondering how they build devices that spray/inject/dispense a finite amount of liquid (to within some amount of error). I wanted to try this ...
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Attaching a M5 screw shaft to a cog wheel
Does anyone know of a good (low profile) way to attach the threaded (chamfered) end of a M5 screw shaft to a 30MM (30T 1M) plastic cog wheel? Would it be a good idea to widen the shaft hole and just ...
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Industrial Robotic Arm
I had the opportunity to work for a factory/company that is in the domain space of production and they want to use a robotic arm for part of the production line.
They want basically a robotic arm ...
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High power jumping mechanism in small robots
I recently saw this video on YouTube featuring a jumping robot: 5 Fastest Robots In The World
I was curious how this is accomplished mechanically? Do they wind a strong spring or use some sort of air ...
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Fastening sheet steel on nylon
I'm trying to attach a small piece of sheet steel (30mm x 50mm x 1mm) to a small piece of nylon (50mm x 50mm x 4mm). Does anyone know how they could be fastened using small screws (
Any thought ...
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How does Fliike Smiirl counter mechanism work
First of all please see this video : http://www.youtube.com/watch?v=n0dkn4ZIQVg
I think there is ony one stepper motor -or servo- working in the mechanisim. But as you can see each flip counter works ...
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Once you understand motors, what's the next step? [closed]
I've gone through tutorials on how to build circuits and control dc, stepper, and servo motors. I may not understand everything about them internally, but i have a good basic foundation.
Now i'm ...
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POM gears and metal fittings
I'm looking at this setup:
where the POM bevel gears are fitted with some kind of metal (bronze?) tube inside which fits over the shaft. What benefits does this method provide? Is it to allow the ...
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Atlas Robot Reference
Boston Dynamics keeps making great robots, however, I dont see any papers that they publish. Although now I can find papers on people using the ATLAS robot, I can not find an original paper detailing ...
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How has the Mars Exploration Rover (MER) has been working for 11 years if it was designed for 90 Sol? [closed]
The Mars Exploration Rover (MER) Opportunity landed on Mars on January 25, 2004. The rover was originally designed for a 90 Sol mission (a Sol, one Martian day, is slightly longer than an Earth day at ...
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What is torque bandwidth in actuated joints and how does it affect the control systems?
The rest of my student team and I are in the process of redesigning an exoskeleton and building it based on an existing one. From the papers that we have been reading there are some references to low, ...
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How to choose a servo motor for solar tracking mechanism?
I design a solar tracking mechanisim. You can see the very undetailed representation in the pic. For choosing a servo motor how can I calculate the torque etc?
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Doubt regarding publishing of robot in a journal or to be applicable for a presentation
i was just curious about publishing an abstract or stuff like that about a robot I've made all by myself .
Do i really need to make a working model of it or 3d solid works or cad will be enough ? .
I ...
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How to seal a threaded rod so I won't lose oil?
I have an M5 threaded rod that penetrates a box. Outside it is driven by a motor and it rotates a part inside the box. The box is sealed and I would like to seal the area around the rod as well. I ...
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Reverse lift mechanism
I have made a RC robot from a wheelchair and I'm planning to attach a snow plow. I'm wondering if there is any mechanism that would be able to lift the plow when reversing.
I have only 2 channel ...
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Lawn mower robot (type of cutter)
If not all, but major types of lawn mower robots are rotary mowers.
I presume1 that reel mower is more efficient, and is said to leave a better lawn health and cut. So, why industry go to the other ...
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How can I attach an arm to a double-flat drive stepper motor?
This is my first robotics experience, outside of one class 10 years ago. I've been Googling this question for about an hour but I can't find an answer!
I'm using a ROHS Step Motor 28BYJ-48 (with an ...
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Is this gear design feasible?
I came up with an idea and am working with a mechanical engineer to design and prototype the idea but I keep sketching out my own ideas in the process and I just came up with this.. I'm quite sure ...
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What to use as electrovalve?
I want do make following installation (blowing bottle tops as music instrument):
...
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What is the Name of the part I'm describing
I'm looking for a part that will do a particular function. It has to be able to move along one axis and tell me the force that is being exerted on it.
Kind of how like a piston moves inside an ...
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Simulation of Robotic arm
I want to simulate my 5 DOF robotic arm, in such a way that the calculated Torque and mass values of each joints (Servos) defined to be tested that are they capable of physically bear all the weight ...
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How do I calculate the direction robot is facing, pose from velocity and yaw rate?
I have a simple car robot with four wheels moving relatively slowly (5~10 mph). The robot has a velocity magnitude and yaw rate sensor and the sensor samples about every 0.1 seconds. I want to map the ...
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How to link ends of timing belt into loop
When I buy some length of timing belt I don't know how to link ends of timing belt into loop.
So far I've found one way to do that (thanks to http://www.lasersaur.com/):
http://www.flickr.com/photos/...
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What motor to use for reciprocating (reversive) movement [closed]
I want to make a copy of this machine Fisher Price Soothing Motions™ Glider and I'm wondering what motor to use? Simple DC motor with appropriate gearbox (slow rpm) or stepper motor?
Here is another ...
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Floppy fish mechanism design
I've bought a floppy fish toy (crab version) for my kid. The toy looks like:
Unfortunately, the toy mechanism inside jams when grabbed and the battery lasts for a short time:
I tried to do my own ...
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How to connect a servo motor and a crank shaft
I have a standard 5v
I am using the horn it came with it, I mean this piece:
Like the long arm in the middle. Each of its holes are 1mm diameter.
Then I have a 3d printed crankshaft I did:
Its ...
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Beginner question about software for calculations
I'm a complete beginner in robotics with background in programming...
I started thinking about a robot project yesterday and want to order some motors to test with. I saw the specs for the motors, ...
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Fuses for mechanical systems
** If there's a better stack exchange site for this, let me know--the mechanical engineering one is closed so I'm not sure where else is appropriate **
Do mechanical systems have fuses?
In an ...
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Good book on mechanisms [closed]
I am working with students (9th & 10th grade) on robotics and wanted to get a good book which covers basic mechanisms. Does anyone have any recommendations. Searching Google or Amazon yields ...
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Is this supposed to be a bearing?
I'm looking at the assembly of a tail rotor that should look like this
original image
I wonder if the "tail output shaft stopper" (circled in red) is meant to be a bearing or just a piece of metal ...
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What is meant by the phrase "movement positional jitter"?
I was searching online for the meaning of this statement but the closest I came across is that jitter here refers to some sort of "deviation".
Therefore, if we say that the movement ...
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Robot mechanism parts names
I'm working on my first "robotic" project that involves a square platform that should drop one of the four sides at a time.
...
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Different methods to determine DOF: Chebychev-Kutzbach-Grubler method vs. Screw method
I'm familiar with Chebychev-Kutzbach-Grubler method to determine degree of freedom of a robot arm. But it seems this method fails to calculate the mobility of some parallel robots, as explained here.
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What's the name of a robot manipulator construction with multiple thin arms joined together?
I am seeing on some videos robots picking items and putting them somewhere in order.
Here are some examples:
https://www.youtube.com/watch?v=wg8YYuLLoM0.
https://youtu.be/ggFdvUlp8YU?t=38
How are ...
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Why do we say a robotic arm have 2 dof even though the two joints rotates along the same axis?
Why do we say a robotic arm has 2 degrees of freedom even though the two joints rotate along the same axis? Why isn't it called a 1 dof robot?
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Dynamic models of parallel robots in the form of multi-mass systems with stiffness coefficients
I want to develop a dynamic model of a parallel robot for control tasks. It is known that equations of motion based on Lagrange equations can be transformed into a state space and use such a model.
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How does this end effector work?
I've seen this linear actuator end effector on a few industrial SCARA 'bots but I am having trouble visualizing how it works internally:
It looks like a type of lead screw, but the nut must spin ...
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Controlling Actuated Robot Hand in Underactuated Manner
We have an allegro hand in our robot, and it is in actuated behavior. In other words, each joint is controlled one or more than one actuator, that is motor. There are 3 actuators for each finger, ...
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