Robotics Stack Exchange
Robotics Stack Exchange

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1500 questions
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4 answers

Is it possible to both move and stabilize a two wheeled robot with no gyroscopes?

With two wheeled robot like this one, I have managed to stabilize it while keeping it stationary. This was done using a digital feedback control system by reading the position of the wheels to determine position, and the natural back electromotive…
rurouniwallace
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EKF-SLAM Update step, Kalman Gain becomes singular

I'm using an EKF for SLAM and I'm having some problem with the update step. I'm getting a warning that K is singular, rcond evaluates to near eps or NaN. I think I've traced the problem to the inversion of Z. Is there a way to calculate the Kalman…
munk
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Nearest-neighbor data structure for non-Euclidean configuration space

I'm trying to implement a nearest-neighbor structure for use in an RRT motion planner. In order to do better than a linear brute-force nearest-neighbor search, I'd like to implement something like a kd-tree. However, it seems like the classical…
giogadi
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Programming a line following robot with reinforcement learning

I am considering programming a line following robot using reinforcement learning algorithms. The question I am pondering over is how can I get the algorithm to learn navigating through any arbitrary path? Having followed the Sutton & Barto Book for…
Lord Loh.
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How does a six-axis force/torque sensor work?

I would really like a six-axis force/torque sensor for my robot, but I just can't afford one. I was thinking about making one of my own. I have experience using strain gauges, but I can't work out how to arrange them so as to create a six-axis…
Rocketmagnet
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Difference between Rao-Blackwellized particle filters and regular ones

From what I've read so far, it seems that a Rao-Blackwellized particle filter is just a normal particle filter used after marginalizing a variable from: $$p(r_t,s_t | y^t)$$ I'm not really sure about that conclusion, so I would like to know the…
Ash
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How can I automatically adjust PID parameters on the fly?

I have a simple servo system that uses a PID controller implemented in an MCU to perform the feedback. However, the properties of the system change dynamically, and so the PID parameters can never be tuned for all circumstances. My robot is a light…
Rocketmagnet
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How do SLAM algorithms handle a changing environment?

I'm doing some groundwork for a project, and I have a question about the current state of SLAM techniques. When a SLAM-equipped device detects an object, that object's position is stored. If you look at the point cloud the device is generating,…
anaximander
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Calculate position of differential drive robot

How do you calculate or update the position of a differential drive robot with incremental sensors? There is one incremental sensor attatched to each of the two differential wheels. Both sensors determine the distance $\Delta left$ resp. $\Delta…
Daniel Jour
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What is the cheapest / easiest way of detecting a person?

I'd like to know if anyone has had success detecting a warm-bodied mammal (ie. Human) using standard off the shelf, inexpensive sensors? Ideally, I'd like to use an inexpensive sensor or combination of sensors to detect a person within a room and…
Yahma
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Connecting More Than Six Analog Input Pins to arduino

I'm in the planning stages for a project using the Arduino Uno to control 8 distance sensors, and have run into a little road block, the Uno only has six input pins. So I'm wondering, is there any way for this to work? If so, how?
Dylan Katz
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Does RRT* guarantee asymptotic optimality for a minimum clearance cost metric?

The optimal sampling-based motion planning algorithm $\text{RRT}^*$ (described in this paper) has been shown to yield collision-free paths which converge to the optimal path as planning time increases. However, as far as I can see, the optimality…
giogadi
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Will turning an NXT motor by hand damage it?

I have heard a lot of claims that manually turning an NXT motor by hand can potentially damage it. I was wondering whether this was at least partially true, and whether there is any evidence to confirm or refute this idea. I know that some projects…
shea
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What was the earliest concept of a robot?

I'm a highschool student studying electronics and for an assessment task on the history of electronics I have decided to focus on the history of robotics. I want to begin with the earliest possible concept of a robot and progress through major…
Jordan
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I don't understand Integral part of PID controller

I dont understand integral part of PID controller. Let's assume this pseudocode from Wikipedia: previous_error = 0 integral = 0 start: error = setpoint - measured_value integral = integral + error*dt derivative = (error - previous_error)/dt …
user561838
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