KinematicPTP

Move as fast as possible along a distance within given kinematic constraints

    KinematicPTP

Library

Modelica/Blocks/Sources

Description

The goal is to move as fast as possible along a distance deltaq under given kinematical constraints. The distance can be a positional or angular range. In robotics such a movement is called PTP (Point-To-Point). This source block generates the acceleration qdd of this signal as output:

KinematicPTP.png

After integrating the output two times, the position q is obtained. The signal is constructed in such a way that it is not possible to move faster, given the maximally allowed velocity qd_max and the maximally allowed acceleration qdd_max.

If several distances are given (vector deltaq has more than 1 element), an acceleration output vector is constructed such that all signals are in the same periods in the acceleration, constant velocity and deceleration phase. This means that only one of the signals is at its limits whereas the others are synchronized in such a way that the end point is reached at the same time instant.

This element is useful to generate a reference signal for a controller which controls a drive train or in combination with model Modelica.Mechanics.Rotational.Accelerate to drive a flange according to a given acceleration.

Parameters

KinematicPTP_0

NameLabelDescriptionData TypeValid Values

mo_deltaq

deltaq

Distance to move

Vector

mo_qd_max

qd_max

Maximum velocities der(q)

Vector

mo_qdd_max

qdd_max

Maximum accelerations der(qd)

Vector

mo_startTime

startTime

Time instant at which movement starts

Scalar

mo_nout

nout

Number of outputs

Scalar

mo_p_deltaq

p_deltaq

Vector

mo_p_qd_max

p_qd_max

Vector

mo_p_qdd_max

p_qdd_max

Vector

KinematicPTP_1

NameLabelDescriptionData TypeValid Values

mo_y

y

y

Structure

mo_y/fixed

fixed

Cell of vectors

true
false

mo_y/start

start

Cell of vectors

Ports

NameTypeDescriptionIO TypeNumber

y

implicit

Connector of Real output signals

output

1