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Available online at www.sciencedirect.com
Energy Procedia 17 (2012) 279 – 285
2012 International Conference on Future Electrical Power and Energy Systems
The Study of the Parameterization of the Drum Brake Design
Based on UG
Liu Hongpu,Peng Erbao
Mechanical Engineering,Henan Polytechnic Institute,Henan473009, China
Abstract
This text apply UG software to the design and study on the type parameter of the brakes. On the basis of the
principles of discretization, discretize the structural pattern of the brake drum. select the typical characteristic of the
brake assemblies and the individual parts of the 3d parameterization modeling work, to build a model for
parameterization library calls.
? 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Hainan University.
Open access under CC BY-NC-ND license.
Keywords: the brakes; ug; parameterization; discretization; research
The brake is the key components of the car industry. with the rapid development and people living
standards improve in the design of the brake the car raised a more stringent requirements. not only to
satisfy the brake the basic properties are required, to satisfy the stringent requirements of the environmental
protection. this article mainly study on the brake drum the parameterization design.
1.The Brake Discretization
With the parameter change, the change situation which in the template characteristic possibly appears:
a) the characteristic maintenance is invariable, is only the size reproduce by pantograph; b) the structure
characteristic changes.
Above two kind of change situation, in actual operation, because selects the template with the
simulated target size difference which must design is not very big, therefore mainly has the first kind of
situation, the size changes in the characteristic maintenance scope. when the parameter change quite is
fierce , is the second kind of situation, this request establishment template must describe the model
comprehensively. Certainly, if a template closer model, the characteristic which must increase manually
are less, but this template has representative and typical nature bad somewhat; The template with awaits
construction the model to have certain disparity, needs to increase manually the characteristic are many,
but its representation and typical nature are good somewhat. This is a pair of contradictory, in the construct
1876-6102 ? 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Hainan University.
Open access under CC BY-NC-ND license. doi:10.1016/j.egypro.2012.02.095
280 Liu Hongpu and Peng Erbao / Energy Procedia 17 (2012) 279 – 285
of the template should find a quite good balance point, like this can both establish the representative
template, and speeds up the spare part the design speed.
Then according to certain separate rule, is separated each model brake the corresponding spare part,
withdraws the typical characteristic from these spare parts, forms the template that the parameterization
design request.
The deference separate rule is:
1.1.Approximate components extraction same characteristic.
1.2.Peculiar part alone carries on the characteristic extraction.
1.3.Carries on the characteristic extraction, should withdraw the similar characteristic as far as possible.
1.4.Characteristic extraction, considers its realization the possibility.
After the drum brake discretization, components is as follows:
Friction disk (about two pieces);
Bbrake shoe ( type);
Sells on consignment
The cylinder body ( type)
Piston ( type);
Leather cup (type);
Brake drum ( type);
Brake shield plate (type);
Fluctuates the supporting pole (type);
Spring (type);
The appendix (bushing dirt-proof boot, piston dirt-proof boot, deflates bolt nut, oil inlet safety
mask, seal packing collar, bolt guards against loose rubber band, separates master cylinder to leave
oil tight sealing ring and each kind of spring and so on)
After above lists only is the discretization the components unification name, regarding under a specific
name, there are many kind of characteristic different components, this request separately establishes the
template, to satisfy the demand about the design, for instance under the cylinder body name, has at least 5
kind of different type cylinder bodies, therefore must establish the template separately. Although extracted
certain cycle of songs's brake to take the template, but has also established many special characteristic
components template, therefore said from essentially, it’s based on each components discretization.After
the choice discretization template components, and defer to the request the size to produce the new
components model, again assembles the brake system.
When each components is parameterized, the parameter integer must control strictly, must use as far as
possible few parameters to describe the entire components. Size which certainly here parameter refers to
the size which is may change, the components majority of sizes needs to use which these to be possible to
change the size actuation (i.e. changes is independent variable, writes is actuated size function form), also
is causes the multitudinous sizes to be connected, causes the overall linkage, completes the
parameterization modeling work.
Liu Hongpu and Peng Erbao / Energy Procedia 17 (2012) 279 – 285
2.Brake Parameterization
This design uses the method based on the characteristic parameterization modeling, realizes the
automobile brake spare part fast design and the automatic design. Therefore needs to make clear following
several with the characteristic correlation concept.
2.1.Characteristic definition
Characteristic is high level abstract description that the designer describe the design object the function,
the shape, the structure, the manufacture, the assembly, the examination, the management and the use
information and the relations which has the accurate project meaning and so on. The characteristic model
use logic in the interdependence, mutually carries on the description and the expression for the influence
semantic network to the characteristic instance and the relations. compare with the low level geometry
element surface, side, expressed the geometry entity method the difference is: The characteristic model
expresses the high level to have the function significance entity, like the hole, the trough and so on, its
operation object is not the primitive geometry element, but is the product function essential factor, the
product technical information and the management information, manifests designer's intention.
2.2.Characteristic classification
Characteristic is the product description information set. The different application domain and the
different object, the characteristic abstract and the classified method is different. Through analyzing
mechanical product massive components blueprint information and the processing craft information, may
constitute the components characteristic to divide into five big kinds:
Management characteristic: With the components management related communications ensemble,
including the title block information (for example components name, chart or illustration number,
designer, design date and so on), the components material, has not poured information such as
roughness and so on.
Technical characteristic: Description components performance and specification communications
ensemble.
Material heat treatment characteristic: associated with components material and heat treatment
communications ensemble, like material performance, heat treatment way, degree of hardness
value and so on.
Precision characteristic: Description components shape, size permission amount of variation
communications ensemble, including common difference (size common difference and shape
position common difference) and surface roughness.
Shape characteristic: The communications ensemble which are related to description components
shape, size, including function shape, processing craft shape, assembly auxiliary shape.
Assembles characteristic: Components correlation direction, mutual active surface and coordinate
relations.
In the characteristic above, the shape characteristic is most important characteristic that describes the
components or the product. Its separable primarily characteristic and the auxiliary characteristic, the former
is used to describe the structure object basic geometry shape, the latter is the characteristic which carries on
the expression to the object partial shape
2.3.Characteristic relation
In order to describe the relation among characteristic, may apply the concept of characteristic class, the
characteristic example. The characteristic class is the description about the characteristic type, is summary
of all same information characteristic. The characteristic example is specific characteristic after the
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characteristic attribute evaluation, is the member of characteristic class. Among the characteristic class, the
characteristic example, the characteristic class and the characteristic example has relation as follows:
Inherits relates level relation among the characteristic, which is located the level
higher authority to be called the ultra kind of characteristic, is located the level lower level to be
called the subgroup characteristic. The subgroup characteristic may inherit the ultra kind of
characteristic the attribute and the method, this kind of inheritance relation is called the relation.
Another kind of inheritance relation is the relation between characteristic class and this kind of
characteristic example, this kind of relation is called the relation. For example, some concrete
circular cylinder is a example that circular cylinder characteristic class, among themselves has
reflected the relation.
Adjacent relation. Reflected the mutual position relations among the shape characteristic, indicated
with CONT. Among the constitution adjacency relation shape characteristic adjacency condition
may share.For example, a steps and ladders axis, between each neighboring two axis section’s
relations are the syntopy, in which each adjacency surface condition may share.
Hypotaxis.the description about shape characteristic compliance or the attached relations, indicated
with IST. The subordinate shape characteristic relies on in the shape characteristic which is
subordinated is existed, like bevel edge attached in circular cylinder.
Quote relation. describing characteristic class as the connection attribute which the quotes
mutually, indicated with RE. The quotation relation mainly exists in the quotation that the shape
characteristic to the precision characteristic, the material characteristic.
2.4.Characteristic modeling
The method that describing product by characteristic as the modeling fundamental element is called
modeling technology based on the characteristic. The characteristic modeling may induce approximately
into three kind of patterns that the interactive characteristic definition, the trick recognition and the design
based on the characteristic.
Interactive characteristic definition. Using the existing geometry modeling system establishment
product geometry model, the user, definition characteristic geometry essential factor in the graph
interactive plan process, and add the information for example characteristic parameter or precision,
specification, material heat treatment and so on to geometry model as the attribute. This kind of
modeling method’s automaticity is low, product data sharing is also difficulty realized, in the
information processing process it is easy to arise the artificial mistake.”.
Characteristic recognition. the characteristic which defines in advance is carried on the comparison
geometry model, definite characteristic concrete type and additional information. Usually it is
composed by the following steps:Searching product geometry database, match characteristic
topo geometry model;Withdraws the characteristic information from the database which oneself
distinguishes;Definite characteristic parameter;Completes characteristic geometry model;
Combines the simple characteristic to become the new characteristic.
The design based on characteristic. The user directly defines components geometry entity with the
characteristic, after soon in characteristic storehouse pre-definition characteristic instantiation, take
example characteristic as basic unit establishment characteristic model, thus completes the product
the definition or the design.
2.5.Parameterization design
Parameterization design is defines the geometric figure size value and agrees the size relations with
group of parameters, provides to the designer to carry on the geometry modeling use. The parameter’s
solution is simple, the parameter and the design object control size has the explicit corresponding relations,
the design result revision receives the size actuation. In the production commonly used the product which
Liu Hongpu and Peng Erbao / Energy Procedia 17 (2012) 279 – 285
monlding in the design object structure shape, the serialized standard letter belongs to this type.
Parameterization design system principle as shown in Figure 1.
Fig.1 Principle of parameterized design system
2.6.Parameter design
In the process of the parameter design, search the restraint relations from the CAD graphic file, then
turn the graph fixed size into the parameterization graph automatic, the new development parameter
cartography software algorithm will be supposed to be advantageous to the old chart parameterization
reconstruction. At present, this is the most methods in the parameterization design applies. Regarding
serialized, universalized and the standardized stereotypia product (for example mold, jig, hydraulic
cylinder, aggregate machine-tool, valve and so on) ’s design the mathematical model and the product
structure which uses all are relatively fixed invariable, only the product mix size have a difference, the
difference of the structure size is caused by the same number and the type datum takes the discrete value in
the different specification product design. This kind of product may replace the basic parameter which
changes along with the product specification with the corresponding variable, then according to these data
and the basic parameter, use the computer automatic inquiry graph database, designs the graph
automatically by the special cartography software on the screen. As shown in Figure 2 for the
parameterization design process.
Fig.2 The course of 3-Dmodel Parameterized design
3.The Three Dimensional Entity Parameterization Design
Parameterization modeling ’s main thought is to show the product model the shape characteristic with
the geometry restraint, mathematics equation and the relations, thus the designs has the similar in the shape
and the function. The parameterization entity modeling ’s key is the geometry restraint relations extraction
and expression, the solution as well as the parameterization geometry model structure. Many kinds of
geometry restraint relations, may write one kind of specific form document including the simultaneous
equation group (i.e. user programming), inputs the computer, actuates geometry design in groups. For
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example, determined a cube ’s constraint condition L, W, H may form using the cube the floor space and
the bottom surface perimeter, face the expression way of artificial intelligence knowledge, this way will
describe the restraint relations of the geometry physique, the geometry and topology with a step logic
predicate form, and will read in the knowledge library. On the one hand the knowledge expression way is
changes into the form by the mark to express each kind of type the data, seeking mark solution; On the
other hand is adds on geometry inference based on restraint, seeking numerical solution, thus realizes the
mechanical product intelligent design in a greater degree. The 3D parameterization model is two major part
is composed by the geometry model and the restraint information. According to on what size restraint and
the order of the topo information model structure, that is the interdependence relations between them, the
parameterization modeling may divide into two kinds successively. One kind is the geometry restraint
acting on the fixed topology physique geometry tissue, geometry restraint value does not change the
geometry model topology, but changes the nominal size of the geometry model.
This kind of parameterization modeling system take B-rep as its internal expression principal-mode.
Another kind is explains the parameterization model the geometry integrant part first and the restraint
relations between them, but model topology is decided by the restraint relations. This kind of parameter
modeling system take CSG expression as internal principal-mode, may change the full-scale mockup
topology, and is advantageous recording structure entire process by the procedural form.
4.The Drum Brake Model Establishment Example
Through to structure analysis of the drum brake separate components, the components modeling may
use three modeling methods.
4.1.Uses the plate work modeling of parts
Plate work modeling and the parameterization process is similar to the entity modeling, through the
two-dimensional schematic diagram plan components correlation characteristic, joins the restraint, and
labels the related size. Using the operation of plate work module in curved side, the pit, the ramming
eliminates and so on producing three-dimensional entity model. And associate main parameter with
secondary parameter through expression . Like Figure 3 is the brake shoe sheet metal model.
Fig.3 The3-D model Parameterized design of sheet metal
4.2.What about rotascope for example the spring use the rule curve function edition modeling
Take the spring as an example, first analyzes the spring structure in each spot, and express the main
parameter for example hypothesis spring outer annulus diameter with the fundamental function, the
internal bore diameter, the turn and so on, then edits rule function of the spring in the rule curve in X, Y,
the Z axis direction on the basis of the main parameter
dia
for example
X1radius r 1 cos dir * 180 * t * rl Y1r Z1 r 1 * sin dir * 180 * t
height wire _
2
r l
Moves
Liu Hongpu and Peng Erbao / Energy Procedia 17 (2012) 279 – 285
these rule curve function, may produce the spring’s central path curve, again through sweeps plunders
produce the spring full-scale mockup, as shown in Figure 4.
4.3.May use the compound method modelling regarding the structure complex components
Regarding the complex shape components often not to be able to realize using several modelling
method any kind above, by now we might use the method above, use several methods to establish the
geometry model we need.As shown in Figure 5 the brake ch