Is an Accelerating Reference Frame Valid for Line Follower Robot Calculations?

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SUMMARY

The discussion centers on the validity of using an accelerating and rotating reference frame for calculations in a line follower robot's control system. The key equations involved are ƩM = Jω' for angular acceleration and ƩF = ma for linear acceleration. The user seeks to determine if inertial forces can be disregarded when the coordinate system is fixed to the robot, effectively simplifying the calculations. The conclusion is that if the robot's coordinate system is stationary relative to itself, the apparent force observed (Fb) can be simplified to F - m_{ab}, where m_{ab} is the acceleration of the reference system.

PREREQUISITES
  • Understanding of Newtonian mechanics, specifically forces and torques.
  • Familiarity with reference frames, particularly inertial and non-inertial frames.
  • Basic knowledge of fictitious forces, including the Coriolis effect.
  • Experience with mathematical modeling in robotics, especially for control systems.
NEXT STEPS
  • Study the Coriolis effect in detail to understand its implications in non-inertial reference frames.
  • Learn about fictitious forces and their mathematical derivations in accelerating reference frames.
  • Explore advanced control system design techniques for mobile robots, focusing on coordinate transformations.
  • Investigate simulation tools for modeling robot dynamics, such as MATLAB or Simulink.
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Robotics engineers, control system designers, and students in mechanical engineering focusing on mobile robotics and dynamics.

MechatronO
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I'm attempting to build a line follower robot and I'm currently in the process of building appropriate models.

For the control system I need to define a coordinate system. The most convinient coordinate system from many point of views would be a coordinate system that moves along and changes direction with the robot, thus a rotating and accelerating reference frame.

The question is if calculations regarding acceleration still would be valid if they are carried out in the same way as in a fixed reference frame.

The calculations to be carried out are:

ƩM = Jω' - Angular acceleration related to net torque applied
ƩF = ma - Acceleration of center of gravity related to net force applied


I've glanced some about information regarding the coriolis effect but I don't really understand it yet. No "loose" object are to be treated in the reference frame.
 
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Aha. That was an interesting article.

The force observed from an arbitrary accelerating and rotating coordinatesystem is

Fb= Fa + F_{fic}

F_{fic} = -(m_{ab} + 2mƩv_{j}u'_{j} + mƩx_{j}u´´_{j})

Fb is the appearent force that an observer in a rotating reference frame would think is acting on an object, while F is the "real" force an observer in an inertial reference frame would see and Ffic is the fictional force coming from the movements of the ref. system and m_{ab} is the acceleration of the ref. system.

I however want a coordinatsystem that is fixed both in position and angle to the robot at a point on the robot which defines position [0,0,0].
The position and velocity in its "own" coordinatesystem would thus be 0.
Will this zero all terms in the Ffic and leave Fb = F - m_{ab} in this particular case?


As the robot would see the acceleration and in combination the force "on itself" in this system as zero we would get back F = m_{ab} if the world of math smiles to me this time?
 

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