# Tag Info

## Hot answers tagged industrial-robot

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Not by merely looking at Jacobian but by looking at the Singular Value Decomposition of the Jacobian, one can see the degrees of freedom that are lost, if lost. Of course it technically somehow turns up to finding the null space but yet I guess it is somewhat familiar and easier. For example let the Jacobian be: $$J = \begin{bmatrix} -50 &... 6 That's not obvious. If I'm in a tank, going 0.5 km/h, I don't need to slow down at all. If I'm in a bobsled going 100km/h and the track banks, I don't need to slow down at all. When you steer, you begin to move around a circle with a particular radius of curvature. This means you also begin to experience centrifugal force.$$ F_c = mv^2/r $$where F_c ... 6 The Kalman filter is an optimal linear filter in the presence of Gaussian noise. It is optimal in the sense that it minimizes the mean-squared error. This means that the covariance of the estimated states will be minimized:$$ P = E\{(x_k - \hat{x}_{k|k})(x_k - \hat{x}_{k|k})^T\}. $$As this covariance is minimized, the goal of any kind of estimation ... 5 TL;DR CNC routers move the tool while CNC mills move the workpiece, but this is a matter of common usage and not based on hard definitions. A router (in the woodworking sense) is just a rotary tool with a cutting bit. Woodworkers consider them a very universal tool, because they can be mounted into shop-made fixtures to create a wide range of other tools. ... 5 For example, how does price vary with precision, speed, reach and strength? The price vary a lot, from a couple of hundreds of bucks to hundreds of thousands of dollars ( Willow Garage's the one-armrobot PR2 costs \285,000 and The two-armed costs \400,000 ), it goes up- as you can guess- whenever the robot arm is precise, fast, long, strong, ... 4 Whether a single 3-way, 2-position pneumatic valve (typically with a work port, an input port, and an exhaust port ‒ see page 3 of nationalpneumatic.com's pdf about valves) will suffice depends on information not given in the question. For example, if you can turn the compressor on or off at will, and if it will hold pressure when off, you can attach the ... 4 Use RoboAnalyzer. It will help you understand what you need. 4 Not a big fan of using head motions or type of spindle to define the difference, as there are lots of exceptions to each. Many 5-axis mills move the head in various ways beyond just Z. Datron makes CNC mills (excellent ones, BTW) that look like these CNC "Routers" but they call them "Mills". Some refer to "Gantry Style" mills as routers. The "Gantry" is ... 4 Industrial Robots with having as aim manipulation of large objects are powered electrically in almost all cases (30-40 years ago there have been popular hydraulic variants). Industrial robots are powered by industrial 400V 3 phase current, so in a sense, they are plugged in a wall outlet, but but a household wall outlet but an industrial one, like this. ... 4 The function you are looking is called online change (e.g. Beckhoff Online Change), at least by some PLC Manufacturers. If you change a few blocks (in case of FBD) or a few contacts (in case of LAD) or a few lines of code (in case of IL or ST) you can do it online by most major PLC manufacturers. (Siemens, Beckhoff and the Codesys world has this ... 4 If you only consider the simple physics of the problem you are completely right, it should be able to move lower payloads at lower velocities and accelerations. However, the maximum payload can only be used as a rule of thumb to dimension a robot. In order to do a proper dimensioning you need the center of gravity, the mass and the inertia of the payload. ... 3 Following a human can be relatively easy, but it depends on your requirements and your sensors on how easy this is. If you use ROS there are some available packages: people_tracker which uses a Kinect. Person-following and Detection in an Indoor Environment: combines a face and leg detector. ppl-detection also uses a Kinect. lidar-tracking: lidar used to ... 3 I have worked on a cartesian robot with similar requirements† as your own, and we selected direct drive synchronous linear motors for our x/y stages. In our case, both axes were around 2m in length, but magnet the tracks have the potential to be as long as you need to build them. † Less than an order of magnitude higher at 2/5ms^{-1} ... 3 On a typical CNC router, the work is stationary and the spindle-head moves in x/y/z coordinates. On a typical CNC mill, the work moves in x/y coordinates (ie, is attached to an x/y table) and the spindle-head moves in the z axis only. An example of each is shown below (photos from pdjinc.com and hylands.net): 3 Given a desired pose:$$T^{desired} = \begin{bmatrix} s_x&n_x&a_x&P_x\\ s_y&n_y&a_y&P_y\\ s_z&n_z&a_z&P_z\\ 0& 0& 0& 1 \end{bmatrix}$$we know that this is given as follows:$$T^{desired} = {}^{0}T_{1}{}^{1}T_{2}{}^{2}T_{3}{}^{3}T_{4}{}^{4}...

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Your Jacobian-based approach is great for velocity control, or when the manipulator is close to the original point. But remember, the Jacobian only gives a first-order approximation to the manipulator's motion. With the highly nonlinear kinematics of manipulators, accuracy will vary throughout the workspace, and will decrease as the step size between the ...

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They are two different ways of getting the same thing. Correctly set D-H parameters will give the exact same kinematics and dynamics as correctly set POE parameters. There are well-defined (although tedious) ways to convert between the two. So "better" or not purely is up to user preference. Some people prefer D-H because for many setups they give a unique ...

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We find this recent paper by Andrea Del Prete, Nicolas Mansard, Oscar Efrain Ramos Ponce, Olivier Stasse, Francesco Nori quite interesting: Implementing Torque Control with High-Ratio Gear Boxes and without Joint-Torque Sensors The authors presented a framework for implementing joint-torque control on position controlled robots.

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For an industrial setting funds are not unlimited but the value of the machine to the process is known or predicted and if the benefit is greater than the cost, the funds are sought. Relationships with suppliers are built up over time. A lot of these relationships are old, passed from one team member to the next. Typically one maintains a relationship with ...

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In short, adaptive control and robust control (Hinf) are the difficult combination of computationally expensive and complicated to understand. Even if you do an excellent job of implementing one of these controllers, after you have move on to another project (or job) the company still needs someone capable of understanding the controller. There are ...

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If I had to guess, I would say that, in an industrial setting, you have a relatively high degree of certainty about the process you're controlling, and/or there isn't much emphasis on transient performance. Arguably, transient performance should be where a more complex controller shines. However, in an industrial setting, once the process is running, all ...

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Each joint of your robot is one motor. They are coupled though kinematic relations and dynamic physics. One straight forward way is to derive these so called 'equations of motion' using the euler-lagrange formalism. Once you obtained your equations you can create for example a Matlab function to solve them dynamically. But back to the modelling part, ...

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In an ideal scenario, yes, that should be the case. When gravity compensation is implemented on robots, all joints apply a torque to balance out the torque applied by the force of gravity. They should ideally turn into floating robots objects. However, it is not always the case due to inaccurate modeling and gravity compensation implementation. Moreover, to ...

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This is a good question, and one you should definitely consider when designing a new robot arm. But unfortunately, it depends a lot on the configuration of your arm (i.e. how the joints will be bent), and how you determine "best" (i.e. are you optimizing for speed, strength, dexterity, etc). And even if you know these things, the metrics you use to ...

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Anki uses optical sensors in their toy cars to implement line followers. The optical sensors are sensitive in the IR range. The fact that the lines cannot be seen is easily explained: The lines are coated with black color which is transparent in the IR range. Paliogen black L 86 or Paliogen black S 84 by BASF are such colors. If you place barcodes along the ...

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Where to get started? Start with an idea, write down its properties, requirements, scope of the robot, its audience. Sketch it on paper. Make a CAD model using Solidworks if you have. You can simulate many properties in Solidworks. You can also import a 3D model of the ECAD file and estimate the production cost. Learn electronics, programmering and take ...

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There are at least two different ways to get it: Explanation 1) For a very special class of mechanical systems like the robotics manipulator, the control law $u=-K_pe+g(q)$ with $K_p$ symmetric positive definite matrix, $e=q_d-q$ (with $q_d$ the set-point and $q$ the actual angular position from the encoders) and $g(q)$ gravitational component leads to ...

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As @acs said, PID control is used for individual joint control. And you ignore all non-linearities. And typically this is good enough. Sure each joint's control isn't completely optimal, but they should be stable. You can have each joint doing position or velocity control. Then you can do trajectory control at a higher level. For whole arm control ...

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I recently worked with DH parameters to define kinematics of my Dual Arm Robot. As per my knowledge and experience, for kinematics I can say that DH Param will be good to use it since that gives you exact location and orientation (provided the table you made is correct) of each link of the robot. I had to work for collision detection between both the arms of ...

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If you are working with windows then for KUKA programs you can use the (OrangeEdit), check it in this website, OrangeEdit Beta. It is free and it enables you to view and edit all the .src and .dat files and more. As for the robot program itself, usually you can save it in a USB key, to do so you just log into the KCP of the robot as administrator (default ...

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