Differenze

Queste sono le differenze tra la revisione selezionata e la versione attuale della pagina.

--- wikifemfuchde2019:lez_2019-05-13 [2019/05/13 11:53] – ebertocchi
+++ wikifemfuchde2019:lez_2019-05-13 [2019/05/13 19:10] (versione attuale) – ebertocchi
@@ Linea 1: / Linea 1: @@
+Initial model
+{{ :wikifemfuchde2019:monocoque_chassis_2019_v000.mud |}}
+just before the break model
+{{ :wikifemfuchde2019:monocoque_chassis_2019_v001.mud |}}
+model at the end of the lesson
+{{ :wikifemfuchde2019:monocoque_chassis_2019_v004.mud |}}
+==== Properties ====
+**Suspension link trusses**
+Solid circular beam sections, ø12mm, aluminum.
+Essentially rigid with respect to other chassis structures.
+**Rear framework**
+Hollow circular section beam, aluminum.
+Main structure: outer diameter ø40mm, wall thickness 1.8mm.
+Stiffeners: outer diameter ø30mm, wall thickness 1.2mm.
+**Composite monocoque**
+Thicker backbone: 1.8mm aluminum sheet, 25.4mm aluminum honeycomb 3003, density 5.2 lb/ft^3 ({{ :wikifemfuchde2019:hex-3003-td.pdf |}}), 1.8mm aluminum sheet.
+Thinner panels: 1.8mm aluminum sheet, 6.75mm same aluminum honeycomb, 1.8mm aluminum sheet.
+Frontal shock absorber support plate: provisionally as thinner panels, to be defined based on shock.
+**Inertial elements**
+{{ :wikifemfuchde2019:monocoque_chassis_2019_inertial_elements_alone.mud |}}
+{{ :wikifemfuchde2019:inertially_equivalent_cuboid_engine.ods |}}
+{{ :wikifemfuchde2019:inertially_equivalent_cuboid_wheel_assemblies.ods |}}
+** Notes: **
+The pedagogical model proposed does **not** include sway/antiroll bars, that are instead a critical element for torsional stiffness loadcases.
+In particular, torsional stiffness should be evaluated in both the limiting cases of
+  * rigid springs, disconnected sway bars;
+  * disconnected springs, rigid sway bar.
+This second loadcase, which is usually neglected, is however relevant for sizing the sway bar support areas on the chassis structure.
+==== Loadcases ====
+  * Static test: torsional stiffness;
+    * preliminary suspension stroke motion test ({{:wikitelaio2016:telaio_monocoque_comeimportato_tutorial_optistruct.mud|original Optistruct tutorial version}} m( );
+    * rigid spring or rigid anti-roll bar?
+  * Front, right wheel bump loadcase (inertia relief);
+  * Frontal crash absorber collapse loadcase (inertia relief); at the element faces belonging to the ''crash_absorber_bearing_area'' set (an approx. 155x320 mm area at the front bulkhead), a 25 psi = 0,172 MPa distributed pressure is applied which is due to the honeycomb absorber crushing  (see {{ :wikitelaio2017:plascore_crushlite.pdf |datasheet}}).
+  * Dynamic modal response;
+  * Dynamic  harmonic response: vertical harmonic load at the front, right wheel, 1-100 Hz range, sampled at 0.25Hz resolution ((100-1)*4+1 = 397 steps);
+==== Connectors ====
+RBE3 link kinematics.
+{{:wikipaom2015:cinematica_rbe3.png?300|}}
+{{:wikipaom2015:cinematica_rbe3_v1.pdf|sorgente ipe}}