New generation of active steering systems distinguishes a need of steering of rear wheels for the reason of directional stability from a need of steering of rear wheels for the reason of cornering at slow speed. Pig 4. in-rhase and Counter-F nase oteerims The 4WS system performs two distinct operations: in- phase steering, whereby the rear wheels are turned in the same direction as the front wheels, and counter phase steering, whereby the rear wheels are turned in the opposite direction. The 4WS system is effective in the following situations: Fig 5: Car in Various Modes Hig VU. babaiel far Kills As can be seen clearly, the car requires just about the same length as itself to park in the spot. Also, since the 360 mode does not require steering inputs, the driver can virtually park the vehicle without even touching the steering wheel. All he has to do give throttle and brake inputs, and even they can be automated in modern cars. Hence, such a system can even lead to vehicles that can drive and park by themselves. Zero steer can significantly ease the parking process, due to its extremely short turning footprint. This is exemplified by the parallel parking scenario, which is common in foreign countries and is pretty relevant to our cities. Here, a car has to park it between two other cars parked on the service lane. This maneuver requires a three-way movement of the vehicle and consequently heavy steering inputs. Moreover, to successfully park the vehicle without incurring any damage, at least 1.75 times the length of the car must be available for parking for a two-wheel steered car. Fig 8: Proposed Design in SOLIDWORKS e Pump and Sensors 2. Calculations for Front Rack-Pinion and Tie-Rod 1. Standard Specifications of Honda Civic (Note: The following calculations are done in SI units only, while for convenience supportive notes are been made) Advantage: In- phase and out- phase turning of rear wheels become simpler and works with in accordance to speed of the vehicle balancing the maneuverability of vehicle. which operates the pump, initiating the control volve to apply hydraulic pressure on telescopic shaft, thus sets the pinion’s motion from primary rack to secondary rack via the reciprocating movement of telescopic shaft. This system even improves control over traditional mechanical four-wheel steering systems. Advantage: The dynamic of these new systems is the full independent control of speed, direction and traction control through the high-speed sensor networks. Fig 13: Newly Designed Spindle A totally new type of spindle is designed for the rear wheels to assist motion of both racks. It consists of 4 arms of which two are for connecting the racks and remaining two for rear suspension. International Journal of Engineering and Innovative Technology (IJEIT) Dablhwwsna 2 Tames 79 The OO A Fig 16: Ackerman Arm Radius SS eS EN Se We will recall that the SIN of an angle is the ratio between the side opposite the angle and the hypotenuse. In shorthand it looks as follows: Where, Where, Raq is the Ackerman Arm Radius Furthermore, because we know the sides of the triangle we can determine angle k in the following manner: 6. Bevel Gear Calculations Minimum number of teeth on front and rear pinion to avoid interference is = 14 Table III: Bevel Gear Specifications In Force Analysis, it is assumed that the resultant tooth force between two meshing teeth of bevel gears is concentrated at the midpoint along the face width of the tooth. Wear Strength of Bevel Gear = 685.610N R = radius of curvature (same as units of wheelbase) = 1.92m = 75.59” Fig 25: Bevel Gear Casing Half Section can conclude that driver has to apply less effort to turn the car, giving much better maneuverability and control on the car. Fig 26: Bevel Gear Casing Assembly Fig 28: Bevel Gear on top deformation Fig 29: Bevel gear on Top Normal Stress Fig 30: Bevel Gear Side Deformation Fig 33: Ball Bearing Normal Stress Fig 31: Bevel Side Normal Stress (Bending) Fig 32: Ball Bearing Deformation Fig 36: Pinion Deformation Fig 35: Normal Stress in Telescopic Shaft Fig 34: Deformation of Telescopic Shaft Material: Grey Cast Iron Fig 41: Spindle Normal Stress iad WUITALU AD Sl aaa Zi-au at viitticl BAJA 2014, Team MPSTME. Also he has done a Technical Internship at Crompton Greaves Ltd, Mumbai in 2013. He has done a course on Pro-Engineer. Currently he is working at Leighton India Contractors Pvt. Ltd., Gurgaon as a Graduate Engineer Trainee. E-mail:vatsalgudhka@ gmail.com
