To design an Omni directional vehicle concept for future development:
To build an Omni Directional Vehicle requires inclusion of an unorthodox approach to mechanics to build a reliable, safe and efficient system capable of carrying humans. It should possess features like enabling easy vision-span transition to enable the user (controller) to look in the direction of motion. It should also have the additional feature of being able to rotate about a single point, unlike contemporary vehicles having fixed radii of rotation. It may suffice that the design concept be capable of moving only in two mutually perpendicular directions (front-back and left-right). But a design with capabilities to move in any arbitrary direction is the main objective.
The mobility of common wheeled vehicles using conventional or skid steering is limited in such environments due to the nonholonomic constraints of their wheels. While they can generally reach any position and orientation in the environment, it may require complex maneuvers. Vehicles with Omni-directional mobility, the ability to move instantaneously in any direction from any configuration, would be desirable for such applications. A truly Omni-directional mobility platform using a pair of Active Split Offset Castors (ASOC) is presented here. This design has been implemented. An active split offset castor (ASOC) module consists of two independently driven coaxial wheels, which are separated at a distance D and connected via an offset link S to the platform at the joint, as shown in Figure.
Fig: An active split offset castor with its coordinate system
Why we used castor mechanism in our Omni directional Vehicle?
The simplest configuration of an Omni-directional vehicle using this approach will have two ASOC modules and one conventional passive castor wheel for static support. For the vehicle to sustain control, all four driving wheels must maintain good traction and thus must remain in contact with the floor at all times. The basic design would require the floor to be perfectly flat to maintain contact. However, in practice floor irregularities such as wires, gaps, bumps at the joints between tile and carpet are unavoidable. Fig: Top view of castor enabled Omni directional vehicle.
1, 3, 5 and 7 are castor wheels.
2 and 6 are driving motors or driving mechanism with gears.
4 is auxiliary base for passive castor wheel.
Basically the vehicle consist of four dual ASOC (active split offset castor), the forward or reverse rolling motion to each castor wheel is provided individually by a motor and the rotation of castor in clockwise or anti clockwise direction is provided with the help of a motor by a gear mechanism for each pair of wheels. The controller (driver) can see the outside environment (traffic) through the mirrors oriented in circular windscreen throughout the vehicle. The driving unit can also rotate or it can be adjusted according to direction of rotation of castor vehicle, so as to comfortably view outside and get the feel of modern vehicles.
Most inspiring natural system has been the human mobile framework of moving in any direction with grace and ease.
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Logic Code on 2008-12-02 14:08:28 wrote,
It is really Good but it really needs intelligent driving..
Rajesh Kumar Gupta on 2008-12-02 20:28:10 wrote,
Vikash Jaiswal on 2009-03-20 19:09:02 wrote,
Rajesh Kumar Gupta on 2009-03-20 20:52:40 wrote,