Questions tagged [design]
Mechanical, electronic or programmatic design of a robot.
147
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Autodesk Inventor 2013: Rounding only at specific edge
I am using Autodesk Inventor 2013 and I need to round a component of a device. I want to round the green marked edges, but not the red marked. But when I click "round", then the bottom edge will ...
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3
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Gears in Autodesk Inventor are looking weird
I use Autodesk inventor professional 2014. I design my gears using the design accelerator. However, whenever I create gear trains, parts of certain gears become transparent. This seems completely ...
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Alternative way to perform Pole zero cancellation?
I've read a lot places that making a controller which cancels the unwanted pole or zero is not good designing practice for designing a controller..
It should make the system uncontrollable which off ...
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1
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LQR design with low effort
I am trying to implement a controller for an inverted pendulum using LQR (with MATLAB command lqr(A,B,Q,R)). The problem is that the motors are relatively weak, so I tried to increase R, but ...
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How to decide about the length of a robotic arm, the base of it and the torque?
I am designing a remote controlled robot which will have a base with three wheels, two of them will be simple wheels at the back of the base and the third will be a ball wheel at the front. It will ...
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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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What do quadcopter propeller specifications mean?
I'm trying to figure out the diameter of tri-blade propellers.
I found a 7x3x4.5 blade, I'm trying to understand the measurements. Is the '7' the length of the blade giving the prop a 10.5" diameter? ...
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Robotic part to dispense candy
I'm a complete newbie trying to build a simple robot that dispenses candy (M&M, skittles, etc). However, since I'm not familiar with the field, I'm having a hard time googling because I don't ...
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Emulation of an Orrery
Orrery is a clockwork model of the solar system. I am trying to emulate one in 2D. Now, to emulate, I need to know what goes on inside. Can someone please explain the basic principle behind the ...
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How to know the desired orientation of a quadcopter?
I am trying to simulate a quadcopter model on Simulink. I want to implement a PID controller for each of X,Y,Z and phi,theta, psi angles. PID gets the error, as input, which is to be minimized.
For ...
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0
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What happened to Butler's car?
Having read the article "This Car Has Electric Brains" in Popular Mechanics, August 1958 I have some questions.
How practical were his methods? Was his work acquired by a car manufacturer or some ...
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Rocker bogie suspension stability
From the designs usually shown of rocker bogie systems, the whole weight of platform seems to be supported by only one rod, be it differential bar or gear. Isn't this a bit unstable system because if ...
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How to open a sliding window?
I live in an apartment that has sliding windows in it. The apartment is naturally warm because we live above a mechanical room, such that we either opened the windows or ran the air conditioning ...
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Is finished plywood a comparable prototyping substitute for polyoxymethylene?
I'm working on a robot with a team, and we're building our robot out of acetal polyoxymethylene (POM) (specifically, delrin) plastic. However, we'd like to prototype the robot before we build it out ...
user2015
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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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Design Calculations & Mathematical Modeling of Tricopters
I have been studying about building a tricopter. But I couldn't find the design calculations or mathematical modeling of the tricopter any where over the internet.
What are the mathematical ...
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What modelling tools are available to design a robot [closed]
I am planning to build a robot.
1) What free or low cost robot modelling tools exist.
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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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If you can create pure yaw motion with a quadcoptor then why won't this work with a tricoptor?
An answer to the question Why are quadcopters more common in robotics than other configurations? said:
You need 4 degrees of freedom to control yaw, pitch, roll and thrust.
Four props is therefore ...
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Most material efficient quadcopter frame
I haven't made or flown any quadcopter, but I am fascinated by them.
But when looking at the frame of a lot of designs, after whachting this video I wondered why a lot the frames are in an X shape. ...
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Aluminum vs Carbon Fiber
So building a quadrocopter from scratch HAS a lot of decision making, and I need some input on the material choice.
I have short listed Aluminum and Carbon Fiber for the Arms and support of the ...
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342
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Drone targeting
Imagine a "drone" and a target point on a 2d plane. Assuming the target is stationary, there are eight parameters:
...
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Dynamic braille interface
I'm a newbie in robotics, and I'm doing a project on dynamic Braille interface. Basically it's a 8*8 array of pins, which can be either totally up or down. How to use least motor as possible?
I'm ...
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Equation to limit rate of change of end-effector in X and Y coordinates
Some vector math is involved here so prepare yourself.
I am developing a robotic arm that moves in two dimensions. It is a rotary-rotary design which looks roughly like the picture in this post:
...
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When should FPGAs be used in Robotics?
FPGA has good points such as a lot of IO points but then again you need to think things on very low level with flip-flops and pioneer on areas where things are not yet mature -- for example see this ...
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What are human-friendly terms for mobile-robot orientation and relative direction of non-robot objects?
Within robotics programming, orientation is primarily given in terms of x, y, & z coordinates, from some central location. However x, y, z coordinates aren't convenient for rapid human ...
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Which is easier/cheaper: Hbridge vs ESC for controlling a motor?
I was able to find a small ESC for about $12 off of ebay. If you were designing a robot, would you see that and think?
\$12 bucks for an ESC that connects to simple pulse-wave interface -
sign ...
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Are power and torque required related in some way?
I am designing a new platform for outdoor robotics and I need to calculate the power and/or torque that is needed to move the platform. I have calculated that I need about 720 W of total power to move ...
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How do I select the best configuration for a known workspace, load and task?
Given workspace constraints, load and task to be done, how do I select the best configuration of my robot? How do I select between a cartesian or Scara robot for instance? How do I select a ...
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Building Robotic arm joint
I am very new to robotic design and I need to determine what parts I will need to assemble an arm joint. The joint will contain one timing belt pulley which a remote motor will be turning, a forearm ...
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Is there a tool for building and analysing robots (kinematics, control) visually?
I am reading research papers about robotics and many of them follow the same pattern:
some construction is established
kinematical formulas are read from the mechanical structure
the state space is ...
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How can I control a fast (200Hz) realtime system with a slow (30Hz) system?
We are currently designing a mobile robot + mounted arm with multiple controlled degrees of freedom and sensors.
I am considering an architecture in two parts:
A set of realtime controllers (either ...
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Getting started with robotic arm design
I would like to design a robotic arm to hold a weight X at length Y (in my case I want to hold X=2.5 lbs at Y = 4 inches). Starting out simply, I would like try building an arm with a gripper plus one ...
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Differences between Ackermann steering and standard bi/tricycles concerning kinematics?
I got the following homework question:
What are the general differences between robots with Ackermann steering and standard bicycles or tricycles concerning the kinematics?
But, I don't see what ...
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How many amps do I want my Switching BEC to provide?
I'm trying to power 7-12 servos, and I was under the impression that each one would need about an amp, but in looking around for an appropriate BEC to supply them, I notice that most seem to output ...
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Why are Mars rovers so slow?
Mars rovers are typically very slow. Curiosity, for example, has average speed of about 30 meters per hour.
Why is it designed so slow? Is it because of some specific power restrictions or for other ...
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MEMS accelerometer calibration
I am trying to calibrate a MEMS accelerometer. I was able to calibrate it for the current axis which is parallel to gravity and shows correctly, 1g. But the other two axes which should be 0.00g are ...
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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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Why do Mars rovers designers prefer wheels over tracks?
Typically Mars rovers use wheels and not tracks. I guess Spirit would have better chances getting out of that soft soil should it have tracks. In general, Mars surface structure is not known in ...
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Why are quadcopters more common in robotics than other configurations?
I've noticed that almost all research being done with helicopter robots is done using quadcopters (four propellers). Why is there so little work done using tricopters in comparison? Or a different ...
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Wheels vs Continuous Tracks (Tank Treads)
I'm building a small robot using some cheap Vex Robotics tank treads. However, my choice of picking tank treads is almost purely based on the fact that they seem like more fun than wheels. I don't ...
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What is the best way to power a large number (27) servos at 5 V?
I apologize if this question may sound a little vague. I am working on a robotics project that will contain 27 servos of various sizes and I am having trouble figuring out how they should be powered.
...
user428
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Effectiveness of a Mobile Robot In Relation To Mass
Do mobile and/or autonomous robots become more or less effective the bigger they get? For example, a bigger robot has bigger batteries, and thus bigger motors, whereas a smaller robot has the exact ...
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Is it better to have batteries distributed at the rotors or the center of the multicopter?
I've seen 3 approaches to mounting batteries on a multicopter:
All the batteries rigidly mounted near the center of the airframe
All the batteries in a bag hanging under the center of the airframe
...
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Is it better to have weight distributed over the wheels or the center of the robot?
When designing a standard 4 or 6 wheel robot, is it better to have the weight distributed primarily in the center of the robot, or over the wheels, or is there no difference?
Specifically, which ...
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Calculating the efficiency of Mecanum wheels
I'm part of a FIRST Robotics team, and we're looking into using Mecanum wheels for our robot.
What are the advantages and disadvantages of using Mecanum wheel versus regular ones? From looking ...
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Choosing the right dimensions for an underwater glider
I'm looking to potentially build an underwater glider, a type of submarine that's slow but can operate on extremely low power draw. However, in order for it to work effectively I've found several ...
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