The current research is intended to minimize the mass of T shaped joint by using lattice structure and topological optimization tool. The stresses, deformation, safety factor of generic and optimized design is evaluated on the basis of these mentioned parameters. The findings have shown that topological optimization method is best as compared to lattice structure method for weight minimization.

1. INTRODUCTION
• Additive manufacturing
• Topology Optimization
• Ansys
• Objectives
• Review of research papers
• Base paper of T Shaped joint & Robotic Arm
手分析
• CAD modelling of Robotic arm & T s
haped joint.
• FEA Analysis using Ansys software
• Topological optimization/lattice struc
ture
CONTENT
01 02
03
RESULTS AND DUSCUSSION
04
REVIEW OF LITERATURE
METHODES
05 CONCLUSION
06 REFRENCES

2. INTRODUCTION
• The current research intended to minimize the mass of T shaped joint And Robotic arm .
• In First case T shaped joint is topologically optimized for weight reduction. The full-scale model (generic) and
topologically optimized model are analysed using techniques of Finite Element Analysis (FEA) to determine
stresses and deformation and comparative analysis is done on the basis of these two parameters.
• In second case study, the robotic arm is optimized for weight reduction using topology optimization technique.
The static structural and modal analysis is conducted on generic design and optimized design using ANSYS
software to determine stresses, deformation, natural frequency and mode shape. The comparative study is then
made on the basis of these parameters.

3. 1.1 ADDITIVE MANUFACTURING
• The term ‘additive manufacturing’ was given by the ASTM F42 committee.
• Additive Manufacturing (AM) is the process of making 3D objects from computer model data by
joining materials layer by layer under computer control using a 3D printer.

4. 1.2 DESIGN FOR MANUFACTURING
Desired
functionality
Topology
optimization
Concept
geometry
Detailed
design
Additive
manufacturing
Post
machining
Final
component

5. 1.3 Topology optimization
• Topology optimization (TO) is a mathematical method that optimizes material layout within a given design
space, for a given set of loads, boundary conditions and constraints with the goal of maximizing the performance
of the system.
• TO is different from shape optimization and sizing optimization in the sense that the design can attain any shape
within the design space, instead of dealing with predefined configurations. The conventional TO formulation
uses a finite element method finite (FEM) to evaluate the design performance.

6. 1.4 Topology optimization: formulation
• Definition of a design domain that contains the structure.
• Discretization of the domain into Finite Elements to evaluate the mechanical or physical responses
• Applications of boundary conditions and load cases
• Discretization of the material distribution: constant density per element) = the design variables
• Optimization algorithm to solve the maximization problem: prediction of new improved design
characterized by a set of density variable map

7. 1.5 ADVANTAGES
Topology Optimization
• Design freedom: part performance not limited by imagination
of designer
• Time to market: fast, nearly automated
design process
• Customization: tailored designs for specific requirements
Additive Manufacturing
• Design freedom: relatively few shape restrictions, complexity
for free
• Time to market: no tooling needed, on-demand production
• Customization: produce many different part at once

8. 1.6 Ansys software
• Topology Optimization technology, Ansys Mechanical gives you the tools you need to design durable
, lightweight components for any application.
• You can define objectives easily and apply controls to ensure that manufacturing requirements are
met, minimum material thicknesses are set and exclusion areas are defined.
• Topology optimization lets you specify where supports and loads are located on a volume of material
and lets the software find the best shape.
• You can now easily perform light weighting of structures, extract CAD shapes and quickly verify the
optimized design.
• You can also simulate spatially dependent materials like composite parts, 3D printed components, and
bones and tissues for more accurate results.

9. 1.7 ANSYS SOFTWARE
Topology
optimization in
Ansys allows
you to:-
• Take into account multiple static loads combined with optimizing for
natural frequencies (modal analysis)
• Satisfy requirements for minimum material thickness
• Observe rules around feature direction (for machining operations for
example)
• Have scope for both cyclic and planar symmetry
• Easily validate results

10. 1.8 OBJECTIVES
1) To optimize the Topology of T shaped Joint using lattice structure and determine stresses and defor
mation under applied loading conditions.
2) To optimize the Topology of Robotic arm using lattice structure and determine stresses and deforma
tion under applied loading conditions.

11. REVIEW OF LITERATURE
02
 Gebisa, A et al. (2017) has conducted topological optimization of jet engine bracket using additive manufacturing. The
topological optimization is very potent method for mass minimization which reduces manufacturing time, cost and materia
l required.
 Gschweitl, M et al. (2018) has worked on mass minimization of spaceflight components using topological optimization t
ools. The component worked is engine support structure of lunar launch vehicle. The process highlighted the feasibility of
additive manufacturing tool for designing and fabrication of flight hardware considering the above situation monitoring.
 Panesar A et al.(2019)has discussed about DFAM (Design for Additive Manufacturing) and compared the procedures and
standards against DFM (design for manufacturing). The application of DFAM in academia is also contemplate

12. • Dapogny et al.(2019) explained and analyzed the properties of materials which are manufactured by additive manufacturing methods
, and also investigated the given facilities. The researcher emphasizing the material extrusion methods which are required for expl
ained the properties of materials which are depending on the trajectory followed using the machine pieces of equipment at the time o
f assembly. The researchers took benefit of AM methods for constructing characteristics. Lastly, several experiments are doing in 2D
to explain the important points.
• Kirkman-Brown et al. (2020) has also discussed about integration of CAD and CAM with additive manufacturing. The topological
optimization tool can be very beneficial in future research works and to process a CAM program that allows the temporal design of a
fabrication parameter which gives a new method of the design of additive manufacturing materials..
• Nirish and Rajendra et al.(2020) has evaluated the various techniques and advantages of additive manufacturing technique against s
ubtractive manufacturing. The waste minimization, design alteration, design flexibility and topological optimization are some of the k
ey advantages. The researcher also discussed the present and future topology optimization method for additive manufacturing. The la
ser beam is used in DMLS/SLM and the electron beam is used in EBM. The consumption of energy is more in EBM so that titanium
alloy is best for fabrication EBM. The researcher shows the different kinds of Metal 3D printing methods and in the space industry, th
ey need lightweight materials. The methods will fabricate the new designs, processes, and materials according to their requirements.

13. 3.1
3.2
Flow chart
• CAD Modelling
Robotic arm and T shape joint in A
nsys design modeler
• FEA Analysis
Robotic arm and T shape joint for
given loading conditions.
• Design optimization
Robotic arm and T shape joint
using TO in Ansys
• FEA Analysis
Optimized Robotic arm and T shape
joint for given loading conditions.
Determine optimized
design stress,deformation,
strain
Determine stress,deforma
tion,strain
CONCLUSION
METHODS

14. 3.2 CAD modeling of robotic arm
Robotic
arm
CAD model
• Modelled in Creo design software using sk
etch, extrude and pattern tool.
• CAD model of lattice structure is develope
d at 50% scale density.
50% scale density
40% scale density
01
02
03
• CAD model of lattice structure is develo
ped at 40% scale density.
01
02
03

15. 3.3 CAD modeling of T shape joint
T shape
joint
CAD model
• Modelled in Creo design software using sk
etch, extrude and pattern tool.
• CAD model of lattice structure is develope
d at 50% scale density.
50% scale density
40% scale density
01
02
03
• CAD model of lattice structure is develo
ped at 40% scale density.
01
02
03

16. 3.4 Importing CAD Model:
• The CAD model of robotic arm and T shaped joint is
imported in ANSYS design modeler and checked for any
geometric errors.
• The imported CAD model is checked for any geomet
ric errors like surface patches, edge errors and other facet
errors etc. The model is then repaired and freed from any
geometric errors
enable to import CAD model in AN
SYS software
CAD Model
• Robotic Arm
• T shape joint
Ansys Design modeler
CAD design file is changed to
Parasolid file format

17. 3.5 Meshing robotic arm
• The number of elements generated is 7003
• and number of nodes generated is 12937
• Similarly, other designs of robotic arm which has lattice structure
of 50% scale density and 40% scale density is also meshed.
• The region with lattice structure has higher density as compared t
o other regions.
lattice structure of 50% scale density
lattice structure of 40% scale density
CAD model (generic design)
• Meshing is an integral part of the engineering simulation process where
complex geometries are divided into simple elements that can be used
as discrete local approximations of the larger domain.
• The mesh influences the accuracy, convergence and speed of the simul
ation.

18. 3.6 Meshing T shape joint
• The T shape joint (without any lattice) is meshed using brick shape.
The brick shape meshing is possible due to topological consistency a
nd absence of any complex shapes.
. .
lattice structure of 50% scale density
lattice structure of 40% scale density
CAD model (generic design)
• The T shape joint (having lattice structure) is meshed using tetrahedr
al elements.
• The mesh density is higher at lattice structure and is lower on other r
egions.
• The number of elements generated is 6630
• and number of nodes generated is 34246

19. 3.7 Loads and Boundary Conditions
The loads and boundary conditions applied on robotic a
rm. The left end is applied with fixed support as shown
by dark blue colour and right end of cylindrical face is
applied with 95.29N loads.
The bottom face of T shaped joint is applied with fixed s
upport and side surface is applied with force of 770N as
shown by red coloured surface. The force is later convert
ed in to cyclic load for fatigue life analysis. The applied l
oad is taken from literature.
Robotic arm
T shaped joint

20. 04
RESULTS AND DISCUSSION
 The FEA simulation is solved using sparse matrix solver.
 The matrix is formulated for elements and assembled to form global stiffness matrix.
 Various matrix operations are carried out like inversions, multiplication to get the results
at nodes and are interpolated to get results for entire element edge length.
 The most popular integral formulation, based on the variational calculus of Euler, is the P
rinciple of Minimum Total Potential Energy.

21. 4.1 Generic Design Results of Robotic Arm
Equivalent elastic strain plot
Deformation plot
• The maximum deformation is observed on right end of robotic arm.
• The magnitude of maximum deformation is .23822 mm
• and while moving away from right end the deformation decreases.
• The leftmost end of robotic arm has no deformation.
• The equivalent elastic strain plot shows high magnitude of strain near
joining member as shown by red and yellow contour on top right port
ion
• The maximum magnitude of elastic strain is .00012966
• while minimum elastic strain is observed on remaining portion of rob
otic arm.

22. Equivalent stress plot
• The maximum equivalent stress plot is observed at joint of arm and body at t
he corner region as shown by red and green colour.
• The magnitude of maximum equivalent stress is .82012MPa which decreases
as we move away from corner edge.
Strain energy plot
• The maximum strain energy observed from analysis is .030084mJ
• and is observed at corner region which decreases as we move toward
s free end of robotic arm.

23. 4.2 Robotic Arm with 50% scale density
Equivalent elastic strain plot
Deformation plot
• The maximum deformation is observed on right end of robotic arm.
• The magnitude of maximum deformation is .014695 mm
• And while moving away from right end the deformation decreases as
shown by dark orange, yellow and light blue colour. The leftmost end
of robotic arm has no deformation (dark blue colour).
• The equivalent elastic strain plot shows high magnitude of strain near
joining member as shown by red and yellow contour on top right port
ion.
• The maximum magnitude of elastic strain is 5.544*10-6 while minim
um elastic strain is observed on remaining portion of robotic arm.

24. Equivalent stress plot
• The maximum equivalent stress plot is observed at joint of arm and body at the
corner region as shown by red and green colour.
• The magnitude of maximum equivalent stress is 1.3824MPa which decreases a
s we move away from corner edge
Strain energy plot
• The maximum strain energy observed from analysis is .0289mJ and
• It is observed at corner region which decreases as we move towards free end of
robotic arm.

25. 4.3 Robotic Arm with 40% scale density
Equivalent elastic strain plot
Deformation plot
• The maximum deformation is observed on right end of robotic arm.
• The magnitude of maximum deformation is .33209 mm and
• while moving away from right end the deformation decreases as show
n by dark orange, yellow and light blue colour. The leftmost end of ro
botic arm has no deformation (dark blue colour).
• The equivalent elastic strain plot shows high magnitude of strain near
joining member as shown by red and yellow contour on top right port
ion.
• The maximum magnitude of elastic strain is .000232 while minimum
elastic strain is observed on remaining portion of robotic arm.

26. Equivalent stress plot
• The maximum equivalent stress plot is observed at joint of arm and body at the
corner region as shown by red and green colour.
• The magnitude of maximum equivalent stress is 2.2884MPa which decreases a
s we move away from corner edge. shown in figure 4.12 above
Strain energy plot
• The maximum strain energy observed from analysis is .0242mJ and is observed
at corner region which decreases as we move towards free end of robotic arm.

27. 4.4 Robotic Arm with Topological Optimization
Total deformation
Topologically optimized geometry
• The topological density obtained after 50% mass reduction.
• The topological density plot is obtained for robotic arm.
• The solid region in between arm has highest scope of material removal.
• These results can be corroborated with equivalent stress plot which sho
ws minimal stress in solid regions at centre of robotic arm.
• The maximum deformation is observed on right end of robotic arm.
• The magnitude of maximum deformation is .29582mm and
• while moving away from right end the deformation decreases as shown
by dark orange, yellow and light blue colour. The leftmost end of robotic
arm has no deformation (dark blue colour).

28. Equivalent stress
• The maximum equivalent stress plot is observed at joint of arm and body at the
corner region as shown by red and green colour.
• The magnitude of maximum equivalent stress is 1.1401 MPa which decreases a
s we move away from corner edge.
Equivalent elastic strain
• The equivalent elastic strain plot shows high magnitude of strain near joining
member as shown by red and yellow contour on top right portion.
• The maximum magnitude of elastic strain is .00016092while minimum elastic
strain is observed on remaining portion of robotic arm.

29. • The maximum strain energy observed from analysis is .021206mJ
• It is observed at corner region which decreases as we move towards free end of
robotic arm.
Strain energy plot
Equivalent stress comparison graph

30. Generic 50% scale lattice 40% scale lattice Topological optimization
Equivalent stress(Mpa) 0.82012 1.3824 2.2884 1.1401
0.82012
1.3824
2.2884
1.1401
0
0.5
1
1.5
2
2.5
Equivalent stress(Mpa)
Equivalent stress comparison graph

31. Deformation comparison graph
Generic 50% scale lattice 40% scale lattice Topological optimization
Deformation(mm) 0.23822 0.33595 0.33209 0.295
0.23822
0.33595 0.33209
0.295
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
Deformation(mm)

32. Generic 50% scale lattice 40% scale lattice Topological optimization
Strain energy (mJ) 0.03 0.028 0.024 0.021
0.03
0.028
0.024
0.021
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
Strain energy (mJ)
Strain energy comparison graph

33. Deformation comparison graph
Generic 50% scale lattice 40% scale lattice Topological optimization
Mass (Kg) 15.091 10.656 10.74 8.85
15.091
10.656 10.74
8.85
0
2
4
6
8
10
12
14
16 Mass (Kg)

34. Design Type
Equivalent stress
(Mpa)
Deformation(mm) Strain energy (mJ) Mass (Kg)
Generic .82012 0.23822 0.030 15.091
50% scale lattice 1.3824 0.33595 0.028 10.656
40% scale lattice 2.2884 0.33209 0.024 10.74
Topological optimization 1.1401 0.295 0.021 8.85
Comparison table for robotic arm

35. 4.5 Generic Design Results of T shape joint
Equivalent elastic strain plot
Deformation plot
• The maximum deformation is observed on right end of T shape joint.
• The magnitude of maximum deformation is .02245 mm and while moving
away from top end the deformation decreases as shown by dark orange,
yellow and light blue colour. The leftmost end of T shape joint has no
deformation (dark blue colour).
• The equivalent elastic strain plot shows high magnitude of strain near joi
ning member as shown by red and yellow contour on corner portion of T
shape joint.
• The maximum magnitude of elastic strain is .00015336 while minimum
elastic strain is observed on remaining portion of T shape joint.

36. Equivalent stress plot
• The maximum equivalent stress plot is observed at T shaped joint as shown by
red and green colour.
• The magnitude of maximum equivalent stress is 30.564MPa which decreases a
s we move away from corner edge.
Strain energy plot
• The maximum strain energy observed from analysis is .00576mJ.
• It is observed at corner region which decreases as we move towards free end of
T shape joint. Further fatigue life analysis is conducted on T shape with fully re
versed cyclic loading..

37. Safety factor plot
• The safety factor plot obtained from analysis.
• The plot shows lower safety factor at joints of T shape member and
safety factor obtained is 2.82.

38. 4.6 T shaped Joint with lattice structure 50% scale
Equivalent elastic strain plot
Deformation plot
• The maximum deformation is observed on right end of T shape joint
• The magnitude of maximum deformation is .0933 mm
• while moving away from top end the deformation decreases as shown by
dark orange, yellow and light blue colour. The leftmost end of T shape
joint has no deformation (dark blue colour).
• The equivalent elastic strain plot shows high magnitude of strain near
joining member as shown by red and yellow contour on corner portion
of T shape joint.
• The maximum magnitude of elastic strain is .0010404 while minimum
elastic strain is observed on remaining portion of T shape joint..

39. Equivalent stress plot
• The maximum equivalent stress plot is observed at T shaped joint as shown by
red and green colour.
• The magnitude of maximum equivalent stress is 207.78MPa which decreases
as we move away from corner edge.
Strain energy plot
• The maximum strain energy observed from analysis is .01149mJ and is
observed at corner region which decreases as we move towards free end of T
shape joint.

40. Safety factor plot
• The safety factor plot obtained from analysis .
• The plot shows lower safety factor at joints of T shape member and
safety factor obtained is .414.

41. 4.7 T shaped Joint with lattice structure 40% scale
Equivalent elastic strain plot
Deformation plot
• The maximum deformation is observed on right end of T shape joint.
• The magnitude of maximum deformation is .04905 mm.
• while moving away from top end the deformation decreases as shown by
dark orange, yellow and light blue colour. The leftmost end of T shape
joint has no deformation (dark blue colour).
• The equivalent elastic strain plot shows high magnitude of strain near
joining member as shown by red and yellow contour on corner portion of
T shape joint.
• The maximum magnitude of elastic strain is .000485 while minimum
elastic strain is observed on remaining portion of T shape joint.

42. Equivalent stress plot
• The maximum equivalent stress plot is observed at T shaped joint as shown by
red and green colour.
• The magnitude of maximum equivalent stress is 95.758MPa which decreases a
s we move away from corner edge.
Strain energy plot
• The maximum strain energy observed from analysis is .00631mJ .
• It is observed at corner region which decreases as we move towards free end of
T shape joint.

43. Safety factor plot
• The safety factor plot obtained from analysis.
• The plot shows lower safety factor at joints of T shape member and
safety factor obtained is .9.

44. 4.8 T shaped Joint with topological optimization
Deformation plot
• The results obtained from topological optimization.
• The plot shows higher mass reduction for base (region with light brown co
lor) while retaining higher thickness at the joint location.
• The topologically optimized geometry is analyzed under same loading
conditions to determine stresses and deformation.
• The maximum deformation is observed on right end of T shape joint.
• The magnitude of maximum deformation is .0207 mm
• while moving away from top end the deformation decreases as shown by
dark orange, yellow and light blue colour. The leftmost end of
T shape joint has no deformation (dark blue colour).
Topological optimization

45. Equivalent stress plot
• The equivalent elastic strain plot shows high magnitude of strain near joining
member as shown by red and yellow contour on corner portion.
• The maximum magnitude of elastic strain is .000146 while minimum elastic
strain is observed on remaining portion of T shape joint..
• The maximum equivalent stress plot is observed at T shaped joint as shown by
red and green colour.
• The magnitude of maximum equivalent stress is 29.119MPa which decreases a
s we move away from corner edge.
Equivalent elastic strain plot

46. Safety factor plot
• The safety factor plot obtained from analysis.
• The plot shows lower safety factor at joints of T shape member and
safety factor obtained is 2.9602.
Strain energy plot
• The maximum strain energy observed from analysis is .00472mJ
• It is observed at corner region which decreases as we move towards
free end of T shape joint.

47. Comparison table of t shape joint
Design Type
Equivalent stress
(Mpa)
Deformation(mm)
Strain energy
(mJ)
Safety Factor Mass (Kg)
Generic 30.564 0.02245 0.00576 2.82 0.22608
50% scale lattice 207.78 0.09333 0.01149 0.4148 0.17684
40% scale lattice 95.75 0.04905 0.00631 0.9 0.18463
Topological optimization 29.119 0.0207 0.00472 2.9602 0.18301

48. Generic 50% scale lattice 40% scale lattice
Topological
optimization
Equivalent stress(Mpa) 30.564 207.78 95.75 29.119
30.564
207.78
95.75
29.119
0
50
100
150
200
250
Equivalent
stress(MPa)
Equivalent stress(Mpa)
Equivalent stress comparison graph

49. Deformation comparison graph
Generic 50% scale lattice 40% scale lattice
Topological
optimization
Deformation(mm) 0.02245 0.09333 0.04905 0.0207
0.02245
0.09333
0.04905
0.0207
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
Deformation
(mm)
Deformation(mm)

50. Strain energy comparison graph
Generic 50% scale lattice 40% scale lattice Topological optimization
Strain energy (mJ) 0.00576 0.01149 0.00631 0.00472
0.00576
0.01149
0.00631
0.00472
0
0.002
0.004
0.006
0.008
0.01
0.012
0.014
Strain
energy(mJ)
Strain energy (mJ)

51. Safety factor comparison graph
Generic 50% scale lattice 40% scale lattice
Topological
optimization
Safety Factor 2.82 0.4148 0.9 2.9602
2.82
0.4148
0.9
2.9602
0
0.5
1
1.5
2
2.5
3
3.5
Safety
factor
Safety Factor

52. Mass comparison graph
Generic 50% scale lattice 40% scale lattice Topological optimization
Mass (Kg) 0.22608 0.17684 0.18463 0.18301
0.22608
0.17684 0.18463 0.18301
0
0.05
0.1
0.15
0.2
0.25
Mass (Kg)

53. 05
CONCLUSION AND FUTURE SCOPE
• The FEA analysis is conducted on robotic arm and T-Shape Joint using ANSYS software.
• The material of robotic arm and T shape joint is reduced by using technique of lattice structure a
nd topological optimization.
• The feasibility of using lattice structure for weight minimization is also assessed by evaluating st
ress, deformation, strain and fatigue life. The detailed conclusion are as following next page

54. For robotic arm, the deformation obtained for lattice design (50% scale) is .33595 mm and in generic design is .23822 mm
which is nearly 41% more.
For robotic arm , the deformation obtained for lattice design (40% scale) is .33209 mm and in generic design is .23822 mm
which is nearly 39.4% more.
For robotic arm, the equivalent stress obtained for lattice design (50% scale) is 1.0465MPa and in generic design is .71MPa mm
which is nearly 47.3% more.
For robotic arm, the equivalent stress obtained for lattice design (40% scale) is 2.2884MPa and in generic design is .82MPa mm
which is nearly 3 times more.
For robotic arm, the mass of robotic arm with lattice design is 10.74Kg and in generic design is 15.091Kg which is nearly
40.5% less.
For T shape joint, the mass T shape joint with lattice design is .17684Kg and in generic design is .22608Kg mm which is nearly
21.7% less.
For T shape joint, the safety factor with lattice design (50% scale) is .414 and in generic design is 2.82 which is nearly 85% less.
For T shape joint, the safety factor with lattice design (40% scale) is .9 and in generic design is 2.82 which is nearly 68% less.

55. REFERENCES
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56. T H A N K Y O U