Among the different methods of drive mobile robots, models of loaders are still the simplest, cheapest and most reliable choice. For feedback and more efficient platform suspension enough even two are driven independently of the wheels – however, as is well known, mechanical stability, can be obtained by providing at least three points of support. The role of the latter may be a third wheel, so-called self-tuning. Much easier and more convenient solution are reference balls that are selected according to the size and weight of the robot.
Reference balls
Ball Caster 3/4" - plastic - Pololu 954
Lightweight plastic ball with a 0.75 inch diameter canopy. Perfect for supporting the front of a two-wheeled robot.Ball Caster 1/2" - metal - Pololu 953
Metal ball in the bowl with a diameter of 1/2 inches, it is ideal to use to support the front of the two-wheeled robot.Ball Caster 3/8'' - plastic - Pololu 950
Lightweight plastic ball in the bowl with a diameter of 3/8 inches, it is used to support the front of the two-wheeled robot.Ball Caster 3/4" - plastic - Pololu 2691
Lightweight plastic ball in the bowl with a diameter of 1 inch, it is ideal to use to support the front of the two-wheeled robot.Ball Caster 3/8'' - metal - Pololu 951
Metal ball in the bowl with a diameter of 3/8 inch. It is ideal to use to support the front of the two-wheeled robot.Ball Caster 1/2'' - plastic - Pololu 952
Lightweight plastic ball in the bowl with a diameter of 0.5 inches. It is ideal to use to support the front of the two-wheeled robot.Ball Caster 3/4" - metal - Pololu 955
Metal ball in the bowl with a diameter of 0.75 inch. Perfect for supporting the front of a two-wheeled robot.See also
The materials of the balls supporting
Available in our offer reference balls are available in two versions: metal and plastic. This first solution is suitable for use in larger, heavier structures, which can additionally be subject to more difficult operating conditions. For example: if the robot will move along the corridors or commercial premises, it is expected that the metal ball will keep longer smooth surface (compared to plastic), which not only affects the processed value of the friction coefficient, but also on the aesthetics of the design. The supporting balls are made of plastic, it is much better to check, and in small structures is their weight, for as long as four times less than the mass of metal balls of the same diameter. In the case of easy and fast robots driven by motors with gearboxes with a relatively low gear ratio, weight is a parameter that is especially important.
With rollers or without?
The small, light balls can support work located directly on the front panel, which simultaneously holds the ball in the proper place (prevent prolapsed) and is a fastening member in General to the chassis of the robot. Thus, the built reference balls with a diameter of 3/8 inch (about 9.5 mm) and? inch (12.5 mm). Large model Ball Caster?” (19 mm) and 1” (25.4 mm) have three rollers mounted on the front panel of 120 degrees. This solution provides a significant reduction in friction and has a positive effect not only on the parameters of control only work, but also on the service life of the constituent elements of the support. The rollers can be in the form of longitudinal rollers or small wheels, which in the upper part of the front panel includes the appropriate cutouts allow free rotation.
All in one
In the case of using balls of the support reactions must be selected such diameter that the basis of the work was at a right angle to the surface – effect on this angle have dimensions and chassis design, method of installation of engines or transmissions, as well as the diameter of the wheels. If you need a more versatile solution, select a set of Tamiya 70144 – by buying this product you get two modules. The height of each of them can be set to any of the following values: 11, 16, 25, 27, 35 37 mm. and Thus is wypoziomujesz a robot platform, regardless of the size of the structure and used wheels.