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10 votes

Optimal location of the center of mass for an inverted pendulum

The two views are not contradictory; they apply to two different situations, which you are treating as a single one. Your personal experience about having a low center of mass applies to situations ...
Ian's user avatar
  • 11k
7 votes
Accepted

Finding Center of Mass for Humanoid Robot

Yes. As @hauptmech mentioned, you can use your forward kinematics to get the center of mass of each link in the base frame. Then you can simply compute the weighted average of the masses and ...
Ben's user avatar
  • 5,855
5 votes

Alternatives to Kalmam Filter

A good choice for sensor fusion with the MPU6050 is a second order complementary filter, which I used for the orientation estimation in a project. The complementary filter is computational cheap and ...
HansPeterLoft's user avatar
4 votes

Balance Bot PID tuning

Just a hint from my extensive experience from self balancing robots: The most important aspect of a self balancing robot, is the actuator acceleration (torque) control. (...) the motors start ...
vmatos's user avatar
  • 71
4 votes

Should I use an arduino to control my balancing robot's motors?

If you want to have a good balancing, PID loop timing is very important. Standard Raspberry OS, like Raspbian can't guarantee you any precise timing, so once your loop period may be 10ms, once it can ...
mactro's user avatar
  • 953
4 votes
Accepted

Can I model a 1D segway as a cart-pole system?

Let's start by defining some of the quantities in the equations you gave: $I$ Inertia of the pendulum about its center of gravity $M$ Mass of the cart $m$ Mass of the pendulum $l$ Distance between ...
Kerry's user avatar
  • 201
3 votes
Accepted

How to balance a humanoid robot on one feet?

Humanoid robots balance and motion planning are not trivial tasks. I believe you will learn a lot if you read about Zero Moment Point (ZMP). Basically, it is a specific point of contact between the ...
Robotawi's user avatar
  • 480
2 votes

Alternatives to Kalmam Filter

Particle filters (epecially in Monte Carlo localization) always seemed easy to intuitively understand to me. You basically simulate bunch of possible states of your robot, rank them with probabilities ...
cube's user avatar
  • 729
2 votes

Optimal location of the center of mass for an inverted pendulum

Lower centers of mass are more stable, but an inverted pendulum is inherently unstable; any perturbation will set it off. The height to center of mass depends on how much track you have available, ...
Chuck's user avatar
  • 16k
2 votes

Loop time for self balancing robot

The answer is not a trivial one. Because, the system dynamics depends on multiple sub-system dynamics (including software, sensors, and actuators (motors in this case)) finding the optimum value for ...
Gürkan Çetin's user avatar
2 votes
Accepted

How to maintain a robot's center of gravity

There are basically two approaches to this problem: You can solve it mechanically or through sensors/programming, or some combination of both. jsotola's response offers several good mechanical ...
MindS1's user avatar
  • 154
2 votes

How to maintain a robot's center of gravity

Use a couterweight. It could be a second arm, or a pendulum inside the robot body, or even two partially filled water resevoirs with a bi-directional pump in between. You could also clamp onto the ...
jsotola's user avatar
  • 532
2 votes

Balancing robot - How to control the velocity and angle

First of all, well done on getting your robot to balance! If you’ve got this far the rest should be easy. A cascading PI loop (no D) works very well for this. You have an outer loop to control the ...
Gareth's user avatar
  • 21
2 votes

Finding center of mass and support polygon for quadruped robot

I intend to find the center of mass of a quadruped robot and find the convex of the CoM inside the support polygon. I want to make a model of this, which is further going to help me develop stable ...
Naman Gupta's user avatar
1 vote

Implementing Dynamic Balancing on Robot Dog

Consider the triangle formed by the three feet that touch the ground. For static balance, the center of gravity's projection needs to be within that triangle. Crouching will lower the CG but won't ...
r-bryan's user avatar
  • 1,271
1 vote

How to balance a long vertical bar

I believe your intuition about using push-pull linear actuators is in the right direction: you would have a quite hard time to control such a structure. Traditionally, to deal with a cart-pole system ...
Ugo Pattacini's user avatar
1 vote
Accepted

Why do I need an additional moment of inertia term in the cart-pole dynamics equation?

Look up an explanation of the parallel axis theorem for the mass moment of inertia. The two terms do represent similar things, but the axis of rotation is different. The term $I \ddot\theta$ comes ...
SteveO's user avatar
  • 4,386
1 vote

Alternatives to Kalmam Filter

Want to get orientations from accelerometers and gyroscopes? Use the Madgwick filter. From the paper, "Results indicate the filter achieves levels of accuracy exceeding that of the Kalman-based ...
Chuck's user avatar
  • 16k
1 vote

Alternatives to Kalmam Filter

Check this website pratical approach to kalman filter it will give you a comprehensive description of kalman filter for a balancing robot (like yours) both theoritical and pratical (you have the code ...
fabrice's user avatar
  • 121
1 vote
Accepted

Accelerometers in a self-balancing robot, can't we do better?

If you properly construct a Kalman filter with an 'x' input, then yes, it'll be better. Notably, the inertial sensor cannot give you an absolute value for x in any case, because you're (essentially) ...
TimWescott's user avatar
  • 1,891
1 vote

Accelerometers in a self-balancing robot, can't we do better?

While this isn't a complete answer to your question, I want to leave some of my thoughts. I think you missed: Gravity itself, which points downward and is typically about 9.81 m/s² but might be ...
SDwarfs's user avatar
  • 301
1 vote
Accepted

Two-wheeled self-balancing robot - Choosing the control system

You only have to do simple calculations. We have done it with different hardware: first with a Lego mindstorm to prototype and then with a powerfull myRIO. The hardware used: Prototype: Balancing ...
kmartinho's user avatar
1 vote

Balancing robot tuning approach

Well assuming you are using a filter(Kalman or Complementary) for the IMU, the PID tuning can be quite a cumbersome task. There is not a fixed end approach on tuning your PID. It took my Self-...
Kartik Madhira's user avatar
1 vote

How can I compensate for pendulum and cart motion when using an accelerometer to detect the tilt angle?

If an accelerometer is mounted along the pole axis of a pole-cart system with its axes oriented tangential and normal to the pole rotation, the components of acceleration can be found using rigid body ...
JDMc's user avatar
  • 136
1 vote

Optimal location of the center of mass for an inverted pendulum

Since your control input to the system acts only on the cart, then you can influence the pendulum angle only due to the coupling between the cart motion and the pendulum motion. If you were to put ...
Kerry's user avatar
  • 201
1 vote

Optimal location of the center of mass for an inverted pendulum

You can answer this by considering the equations of motion of an inverted pendulum: $$\ddot{\Theta} = \frac{g}{l} \sin(\Theta)$$ If you agree that the easiest system to control is that which has the ...
SteveO's user avatar
  • 4,386

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