Fahruddin, Eko Tegar (2026) Optimasi Geometri Sepatu Circular Re-entrant Auxetic untuk Memaksimalkan SEA dalam Mitigasi Gaya Kontak dan Evaluasi Respons Aktuator RB03 pada One Legged Robot. Other thesis, Institut Teknologi Sepuluh Nopember.
![[thumbnail of 5007221080-Undergraduate_Thesis.pdf]](http://repository.its.ac.id/style/images/fileicons/text.png) |
Text
5007221080-Undergraduate_Thesis.pdf Restricted to Repository staff only Download (5MB) | Request a copy |
Abstract
Perkembangan quadruped robot dengan mobilitas tinggi membutuhkan sistem kaki yang mampu mengurangi beban impulsif pada fase touchdown. Gaya kontak yang meningkat dalam waktu singkat dapat menimbulkan shock load, meningkatkan torsi pada aktuator, serta memperbesar risiko kerusakan pada struktur kaki dan komponen transmisi. Penelitian ini mengembangkan Sepatu berbasis struktur circular re-entrant auxetic sebagai solusi mekanis pasif untuk meningkatkan penyerapan energi, menurunkan gaya kontak, dan memperbaiki respons dinamis aktuator RB03. Parameter sudut re-entrant dan ketebalan strut dioptimasi menggunakan Multi-Objective Genetic Algorithm dengan fungsi objektif memaksimalkan Specific Energy Absorption (SEA) dan meminimalkan tegangan maksimum, sedangkan stiffness digunakan sebagai batas kelayakan desain. Analisis numerik dilakukan menggunakan ANSYS 2025 R1 melalui simulasi Static Structural dan Explicit Dynamics. Desain optimal kemudian diproduksi menggunakan material TPU 95A dengan metode FDM dan diuji pada sistem one-legged robot dengan membandingkan Sepatu auxetic terhadap Sepatu rubber konvensional. Hasil optimasi menghasilkan sudut re-entrant sebesar 62,15° dan ketebalan strut sebesar 0,9 mm. Dibandingkan desain baseline, SEA meningkat dari 825,571 menjadi 1.019,748 mJ/kg atau sebesar 23,52%, sedangkan tegangan maksimum menurun dari 2,121 menjadi 2,0644 MPa atau sebesar 2,67%. Desain optimal menunjukkan karakteristik gradual stiffness dengan nilai simulasi sebesar 1,068; 3,004; dan 3,102 N/mm pada tiga fase deformasi. Hasil eksperimen menunjukkan pola yang serupa dengan perbedaan rata-rata terhadap simulasi sebesar 19,00%, meskipun stiffness fase ketiga mencapai 3,749 N/mm dan melebihi batas desain sebesar 7,10%. Pada simulasi tumbukan, Sepatu auxetic menurunkan peak force sebesar 36,63%, loading rate gaya sebesar 23,01%, dan tegangan yang diteruskan ke struktur utama sebesar 86,22%. Pengujian drop test menunjukkan bahwa Sepatu auxetic menurunkan rata-rata peak contact force dari 42,8 menjadi 35,6 N atau sebesar 16,8%, serta meningkatkan waktu kontak dari 0,477 menjadi 0,641 s atau sebesar 34,4%. Estimasi GRF berdasarkan torque feedback juga menurun dari 116,68 menjadi 96,17 N atau sebesar 17,58%. Penggunaan Sepatu auxetic menurunkan peak torque feedback dari 11,19 menjadi 8,80 Nm sebesar 21,29%, loading rate torsi dari 64,91 menjadi 55,48 Nm/s sebesar 14,53%, dan settling time dari 0,6074 menjadi 0,4821 s sebesar 20,63%. Hasil tersebut menunjukkan bahwa deformasi geometris dan karakteristik gradual stiffness struktur auxetic mampu memperpanjang proses transfer beban, mengurangi gaya dan torsi puncak, serta mempercepat stabilisasi aktuator setelah tumbukan. Sepatu auxetic dengan demikian berpotensi menjadi solusi mekanis pasif untuk mengurangi shock load dan meningkatkan keandalan sistem kaki robot.
=====================================================================================================================================
The development of high-mobility quadruped robots requires leg systems capable of reducing impulsive loads during the touchdown phase. A rapid increase in contact force over a short period can generate shock loads, increase actuator torque, and raise the risk of damage to the leg structure and transmission components. This study develops a circular re-entrant auxetic shoe as a passive mechanical solution to improve energy absorption, reduce contact force, and enhance the dynamic response of the RB03 actuator. The re-entrant angle and strut thickness were optimized using a Multi-Objective Genetic Algorithm, with the objectives of maximizing Specific Energy Absorption (SEA) and minimizing maximum stress, while stiffness was used as a design feasibility constraint. Numerical analyses were conducted using ANSYS 2025 R1 through Static Structural and Explicit Dynamics simulations. The optimized design was subsequently fabricated from TPU 95A using the FDM process and tested on a one-legged robot system by comparing the auxetic shoe with a conventional rubber shoe. The optimization produced a re-entrant angle of 62.15° and a strut thickness of 0.9 mm. Compared with the baseline design, SEA increased from 825.571 to 1,019.748 mJ/kg, corresponding to an improvement of 23.52%, while the maximum stress decreased from 2.121 to 2.0644 MPa, corresponding to a reduction of 2.67%. The optimized design exhibited gradual stiffness characteristics, with simulated stiffness values of 1.068, 3.004, and 3.102 N/mm across the three deformation phases. Experimental results showed a similar response pattern, with an average difference of 19.00% relative to the simulation. However, the third-phase experimental stiffness reached 3.749 N/mm, exceeding the upper design limit by 7.10%. In the impact simulation, the auxetic shoe reduced peak force by 36.63%, force loading rate by 23.01%, and stress transmitted to the main structure by 86.22%. Drop-test experiments showed that the auxetic shoe reduced the average peak contact force from 42.8 to 35.6 N, corresponding to a reduction of 16.8%, while increasing the contact time from 0.477 to 0.641 s, corresponding to an increase of 34.4%. The GRF estimated from torque feedback also decreased from 116.68 to 96.17 N, representing a reduction of 17.58%. The use of the auxetic shoe reduced peak torque feedback from 11.19 to 8.80 Nm by 21.29%, torque loading rate from 64.91 to 55.48 Nm/s by 14.53%, and settling time from 0.6074 to 0.4821 s by 20.63%. These results demonstrate that the geometric deformation and gradual stiffness characteristics of the auxetic structure can extend the load-transfer process, reduce peak force and torque, and accelerate actuator stabilization after impact. Therefore, the proposed auxetic shoe has the potential to serve as a passive mechanical solution for reducing shock loads and improving the reliability of robotic leg systems.
| Item Type: | Thesis (Other) |
|---|---|
| Uncontrolled Keywords: | circular re-entrant auxetic, Sepatu, MOGA, Specific Energy Absorption, gaya kontak, aktuator RB03. circular re-entrant auxetic, Sepatu, MOGA, Specific Energy Absorption, contact force, RB03 actuator. |
| Subjects: | T Technology > TJ Mechanical engineering and machinery > TJ211 Robotics. T Technology > TJ Mechanical engineering and machinery > TJ223.A25 Actuators. |
| Divisions: | Faculty of Industrial Technology > Mechanical Engineering > 21201-(S1) Undergraduate Thesis |
| Depositing User: | Eko Tegar Fahruddin |
| Date Deposited: | 04 Aug 2026 01:13 |
| Last Modified: | 04 Aug 2026 01:13 |
| URI: | http://repository.its.ac.id/id/eprint/142744 |
Actions (login required)
 |
View Item |