Page 278 - Robot Design Handbook ROBOCON Malaysia 2019

direction of its wheels. Omni-wheels are also used to minimize drag. This is because they

are light, simple, and has the best performance when travelling diagonally. The Omni-
wheels are usually bumpy and has low torque for pushing but the rotation speed can be

adjusted wirelessly depending on the torque produced by the motors.

Figure 1: The omni-wheel

2.1.1.2 Gripping and Shooting Mechanism

Shooting mechanism consists of two main parts; 1) grip-and-throw part; and 2) air-
tank system. Grip-and-throw part is made of aluminium. This is because aluminium is a

light-weight material and malleable. The gripping part is covered with a layer of silicon to

increase the friction between the Shagai and the part. The grip-and-throw part motion
depends on a hydraulic system i.e. via the piston principle. Pressure is applied to the piston

to generate a force to grip-and-throw the Shagai. The air-tank system is also used to assist
the gripping and shooting mechanism system. Air-tank system consists of pneumatic part

and pumped bottles. The pneumatic part contains numerous tubing to transfer pressure to

the hydraulic system. Bottles are pumped before the competition to supply enough pressure.
We have used soft-drink-water bottles because of the lining of the bottles are thick enough

to withstand the pressure. The cap of each bottle is sealed with epoxy to avoid leakage of
air. Six bottles are pumped until pressure has reached six bars or above each.

2.1.1.3 Problems Faced

There were two main problems in the development of our robots. They were:

 Dimension error

 Insufficient of power

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