Analisa Kekuatan Chassis Mobil Listrik “Braja Wahana” Chassis Hollow Dengan Variasi Ketebalan

Pengembangan Molina (Mobil Listrik Nasional) melibatkan beberapa perguruan tinggi nasional, salah satunya ITS. Dalam proses pengembangan Molina oleh ITS, dengan nama Braja Wahana, diawali dengan proses perancangan dan penelitian. Proses perancangan dan penelitian Braja Wahana, terdapat beberapa parameter penting, antara lain daya motor listrik, transmisi daya dari motor listrik ke roda, stabilitas kendaraan, center of gravity, dan reliability mobil listrik. Mobil harus dalam kondisi stabil ketika akselerasi, deselerasi, maupun saat belok. Kestabilan kendaraan berhubungan dengan kekuatan dari chassis yang dapat disimulasikan dengan parameter tegangan Von-Mises, safety factor, dan deformasi. Selain analisa tersebut, nantinya juga didapatka blue print chassis dari Braja Wahana. Dalam tugas akhir ini, prosedur penelitian dilakukan dengan beberapa tahapan yang dimulai dengan melakukan analisa-analisa dengan sumber literatur buku jurnal, dan penelitian sebelum-sebelumnya. Tahap selanjutnya pengumpulan data-data teknis untuk perhitungan beban dan penentuan kokoordinat pembebanan yang selanjutnya dilanjutkan pada tahap simulasi. Geometri desain dari software CAD di masukkan ke software simulasi. Selanjutnya dilakukan meshing untuk ii memecah geometri menjadi bentuk-bentuk kecil, kemudian penentuan Constraint atau boundary condition sebagai titik tumpu dari chassis. Tahap selanjutnya dimasukkan pembebanan pada kokoordinat-kokoordinat yang sudah dihitung. Kemudian didapatkan hasil simulasi berupa tegangan Von-Mises, safety factor dan deformasi. Pada simulasi chassis dengan ketebalan 1.2 mm didapat nilai tegangan Von-Mises dan deformasi maksimum serta nilai safety factor terkecil pada pembebanan vertikal sebesar 58.95 MPa, 0.69 mm dan 5.85,\ud pembebanan akibat belok sebesar 206.47 MPa, 1.61 mm dan 1.67, pembebanan akibat akselerasi sebesar 112.32 MPa, 1.4 mm dan 3.07 dan pembebanan akibat pengereman 143.68 MPa, 2.3 mm dan 2.40. Sedangkan chassis dengan ketebalan 1 mm didapat nilai tegangan Von-Mises dan deformasi maksimum serta nilai safety factor terkecil pada pembebanan vertikal sebesar 147.34 MPa, 1.06 mm dan 2.34, pembebanan akibat belok sebesar 503.48 MPa, 0.69 mm, dan 0.68, pembebanan akibat akselerasi sebesar 273.68 MPa, 1.94 mm, dan 1.26 dan pembebanan akibat pengereman 283.24 MPa, 4.01 mm, dan 1.21. Chassis dengan ketebalan 1 mm memiliki tegangan Von-Mises maksimum diatas batas yieldnya dan nilai safety factor dibawah safety factor yang diizinkan Oleh karena itu, chassis dengan ketebalan 1 mm tidak aman untuk digunakan. ======================================================================================================= The development of Molina as a National Electric Vehicle has been involving several state universities, including ITS. The proccess of Molina’s development by ITS, named as Braja Wahana, starts with designing proccess and researches. There are severeal important parameters that affect the car performance on the road. Some of them are power electric motors, power transmission from the electric motor to the wheels, vehicle stability, center of gravity, and reliability of electric cars. Vehicle stability is the most important part when a car drove up the street. Vehicle stability is the most important part a car drove up the street. The car must be in stable condition when accelerates, decelerates or changing direction.Vehicle stability can know with the results of simulation. The results of simulation are Von-Mises stress, safety factor, and deformation. In this thesis, the research procedure performed with several stages begins with analysis sourced from journal literature, and recent researches. The next stage is iv collecting technical data for the calculation of loads and determination of cokoordinates of the next loading resumed in the simulation phase. Geometry design of CAD software incorporated into the simulation software. Furthermore, meshing is applied to divide the geometry into small forms, then the determination of constraint or boundary condition as the support of the chassis. The next stage is to enter the loads on the cokoordinates that have been calculated. Von Mises, deformation, and Safety factor are the result of this simulation. In the simulated chassis with a thickness of 1.2 mm, Von Mises and total deformation maximum stress obtained, with the smallest safety factor value in the vertical loading of 58.95 MPa, 0.69 mm and 5.85, loading due to turn of 206.47 MPa, 1.61 mm and 1.67, loading due to acceleration of 112.32 MPa, 1.4 mm and 3.07 and loading due to braking 143.68 MPa, 2.3 mm and 2.40. While the chassis with a thickness of 1 mm obtained a maximum value of Von-Mises stress and the value of safety factor at the smallest vertical loading of 147.34 MPa, 1.06 mm and 2.34, loading due to turn of 503.48 MPa, 2.53 mm and 0.68, loading due to acceleration of 273.68 MPa, 1.94 mm and 1.26 and loading due to braking 283.24 MPa, 1.22 mm and 1.21. Chassis with a thickness of 1 mm with a maximum Von Mises stress and the smallest safety factor value only occurs in certain areas only. Therefore, a chassis with a thickness of 1 mm is not safe to use