﻿ Symbols

# Symbols

#### Kinematics-Tree Structure & Symbols

Symbol at top of 'Kinematics-Tree'

 'Unsolved' and 'Solved' Mechanisms Symbol Kinematic-Chain is: Mobility Means Unsolved Mechs Mobility is not Fully-Defined. M > 0 The kinematic-chain is not fully defined, You cannot get kinematic-data from Points in these kinematic-chains. Solved Mech Mobility is Fully-Defined. M = 0 See: Mobility is Zero This is your goal. The kinematic-chain is a 'kinematically-defined chain'.

Kinematic Sub-Assemblies

Kinematic-Sub-Assemblies are:

 • Motion-Parts
 • Geared-Rockers
 • Dyads
 • Pulley-Rockers
 • Rack-Pinions

Solved and Unsolved Mechanisms [Kinematic-Trees].

The sub-assemblies have one symbol in three colours. The colour of the symbol may change as you cycle the machine.

Summary of Symbols:

 • - solves for a complete machine cycle.
 • - is solved now, but it does not solve [it breaks] for at least one period in the machine cycle.
 • - does not solve now, at this machine angle.

Example.

Kinematic-Chain with four sub-assemblies:

 • Rocker,
 • Geared-Rocker,
 • R-R-R Dyad, and
 • R-R-R Dyad[2].

Example 1

 • The Symbol is :
 • The Dyad is solved for a machine cycle [0-360 of the Master Machine Angle].

Example 2 : A Dyad that 'Breaks'...

 • The Symbol is :
 • The Dyad is solved now, but it does not solve for all positions of the machine cycle [0-360 of the Master Machine Angle].

Example 2 : - The Dyad later in the machine cycle

 • The Symbol is :
 • The Dyad is not solved 'now' and at this position of the machine cycle [0-360 of the Master Machine Angle].

You can explore the basic elements of kinematic-chains.

At this level you can see:

 • Parts
 • Joints
 • Motion-Dimensions
 • Gear-Pairs
 • Pulley-Joints

The symbol, , also shows next to the elements in each sub-assembly.

Example 1

 • The symbol is to show the Dyad is solved for a complete machine cycle.
 • The symbol is next to each element in the dyad to show they are solved for complete machine cycle.

Example 2

 • The symbol is  to show the Dyad does not solve at some instant in the machine cycle.
 • The symbol also shows next to the elements in the dyad that are not solved at some instant in the machine cycle.

Example 2

 • The symbol is : to show the RRR Dyad is not solved at this instant in the machine cycle.
 • The symbol also shows next to the elements in the dyad that are not solved at this instant in the machine cycle.

#### A typical Kinematics-Tree

This Kinematics-Tree has three kinematic-chains:

 1 Three Kinematic Defined Chains, identified by the icon.
 a. Two Rockers
 b. A Rocker with an RRR Dyad

A Rocker is expanded to show three elements:

 1 Pin-Joint
 2 Part4
 3 Mot-Dim Lin: Slider Motion-Dimension

The RRR Dyads [broken] is expanded to show it is assembled from:

 1 Three Pin-Joints
 2 Two Parts

Dyad and Joint Symbols:

This symbol is alongside a Dyad and Joint when it does not break at any instant in the machine cycle.

This symbol is alongside a Dyad and Joint if a Joint brakes at some instant in the machine cycle.

This symbol is alongside a Dyad and Joint while it is broken, or at this instant, in the machine cycle.

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