Share Your Experience: Take the 2024 Developer Survey

# Tag Info

### Why do people use camera instead of laser sensor for robot navigation?

A 3D laser range finder or LIDAR such as the one on the Google Car is far more expensive than a camera. The other reason is that while in case of a LIDAR the distance of every pixel is available, the ...
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### How do I determine the required encoder resolution for a control system?

First I would question your math that got you to the 12b sensor. If you have a $dy$ of 1 mm over an arm that is $r = 1$ m long, then $\sin(\theta) = dy/r \rightarrow \theta = \mbox{asin}(dy/r)$. If ...
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### Instantaneous velocity calculation from accelerometer?

The only way to get a velocity from an accelerometer is to numerically integrate the output of the accelerometer. That is, $$v = v_0 + a*dT \\$$ where $dT$ is the elapsed time between ...
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### Stabilising an inverted pendulum

There are lots of ways to solve this problem, which falls into the category of Control Engineering. There are two standard approaches: Classical Control: The control command has to be proportional ...
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### How to measure pull force on a (kite) rope?

The component you highlighted is called a tensile load cell. You could buy one from a supplier, but it probably would be cheaper to buy a cheap digital hanging scale and taking the sensor out of it - ...
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### What is the difference between active and passive sensors?

Let's recall that sensors are used to measure a physical quantity. The distinction between passive and active sensor characterize the sensor ability to retrieve a measurement without or with inputing ...
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### PID and Kalman filters

There isn't really a relationship between them, unless you're asking how the dynamics feed each other when combined into a system. If that's the case, then I would suggest maybe starting with a ...
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### Detection of linear acceleration vs rotational velocity/acceleration

The IMU itself cannot distinguish between "true" linear acceleration and "fictitious" (Coriolis) linear acceleration induced by rotation of the IMU coordinate frame with respect to ...
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### Measure weight of an object using a servo

This is going to depend on the style of motor in the servo and the style of gearbox. If the servo can't be back-driven when unpowered, then it's likely some form of a worm gear assembly that will ...
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### Do multiple LIDAR systems in same area interfere?

Based on two different company's sensors for use in autonomous cars - yes they do interfere. And honestly, I am not sure what is going to happen when you have 30 cars in an intersection, the noise ...

### Why do people use camera instead of laser sensor for robot navigation?

In addition to those points in Bence's answer, cameras can: Calculate many complex features that result in very robust matching between frames, and object recognition High angular resolution (typical ...
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### How can I compare robot and human hands?

The only benchmark I know in development is at NIST. Their Intelligent Systems Division project page should help. On that page they discuss the specific possible metrics of grasp cycle time, grasp ...
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### How can I compare robot and human hands?

You should check out: The Yale-CMU-Berkeley (YCB) Object and Model set. It is designed for facilitating benchmarking in robotic manipulation. The set consists of objects of daily life with different ...
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### Is it better to use software or hardware for object sorting?

It really depends on the objects you are sorting, and the flexibility you're looking for as the system is maintained over the years. Using physical methods to sort is very reliable. Many times you ...
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### Noisy magnetometer data

First, let's look at if your findings seem reasonable given the datasheet specifications for the sensor. For this, I'll assume that Wikipedia is generally correct and that the strength of Earth's ...
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### Stabilising an inverted pendulum

The theory that describes what you are looking for is call Control Theory. Search for the Nonlinear Systems textbook by Hassan Khalil for an excellent overview of the material--the inverted pendulum ...
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### Shield IMU from magnetic interferences

Nope. Magnetometers measure the magnetic field. The field it's measuring is going to be the sum of fields from a variety of sources. The field you're interested in is the earth's. But it is not ...
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### Why do people use camera instead of laser sensor for robot navigation?

navigation in urban environments Depending on the laser, there might be legal constraints on where you can use it. Running around town throwing laser rays around might require special permission/...
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### Do multiple LIDAR systems in same area interfere?

One could use lasers with slightly different wave length - just as different channels for Wi-Fi signal. Also there could be used some kind of wave modulation... but I don't think LIDARs use such ...
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### Is there a sensor that can measure through an object?

I am not sure you will be able to find a cheap off the shelf sensor. But if you are an RF engineer and willing to implement something yourself, you might want to read: A Multifrequency Radar System ...
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### Reading Intention for exoskeletons motion estimation

You have many options: encoders at exo joints to provide absolute angles, IMU on limbs for estimating motions, force sensing shoe soles for force distribution, force sensors at joints, crutches ...
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### Is it better to use software or hardware for object sorting?

You would have to do both. It's very very challenging to move an object without using hardware, and it's incredibly hard to see the colour of a brick with hardware. You'd have to break it down into ...
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### Can high voltage power lines provide a super highway for drones?

Sure, a drone can land on a powerline. That's a standard task like the "peg in hole problem" for robotarms. The aim is to maneuver a UAV near to a highvoltage line and eating all the energy. The ...

### Can high voltage power lines provide a super highway for drones?

I think yes it can but how? My options are here: Static system for conventional systems It should stand or hang to line/pole/special place like birds. Please watch video for an example: https://www....
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### A sensor that can see glass/transparent objects and surfaces

Unless you need very good resolution or a very tight detection pattern, I would go with an ultrasonic sensor. They can be very cheap and easily meet your detection range specs, for the very low end ...
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### A sensor that can see glass/transparent objects and surfaces

I'm pretty sure that a very basic IR proximity sensor would do the trick. Glass is opaque to all but visible light. IR (as well as UV) will not penetrate the glass and you ought to be getting reliable ...
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### PID and Kalman filters

The Kalman filter optimizes the estimate of the system state in the presence of measurement errors and model errors. PID tries to drive a particular model/measurement system to a chosen state.
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### Joint torque sensor vs end-effector force sensor

If everything were ideal, then your thinking is correct. In practice, though, there are many accumulated errors both in the sensors and in the real vs modelled Jacobian. So if what you care about most ...
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The answer is $\vec{G}$! and also any $\vec{\tau}$ torque caused by it, if the axis connecting the geometrical center of the sensor (assuming it measures torques relative to its geometrical center) to ...