Page 134 - Robot Design Handbook ROBOCON Malaysia 2019

Aluminium is used as it is light, easy to process yet very durable. The weight limit for this

competition is 50 kg which means the selection material is very crucial. Four
omnidirectional wheels are used for robot’s movement (see Figure 4). These four wheels

enable the robot to move in various directions just by controlling the movement of the motor
[5]. We used a geared motor so that it has enough torque to carry the weight of the body of

the robot. A suspension system is used to ensure that the robot can move on an uneven

game-field.

Figure 4: An example of an Omni wheel and the direction it can travel

As for the Gerege, it uses a pneumatic cylinder, placed in a slot. The robot must also

lift and throw the Shagai. The lifting of the Shagai is done using arms utilizing linkage

mechanism and powered by a worm geared motor. This is done so that the arm will not fall
when it is not powered up. The gripping and throwing of the Shagai is done using a

pneumatic push mechanism. A cylinder is used to push the Shagai. The pneumatic system
is a portable system in which compressed air is filled in tanks, made from plastic bottles and

the cylinders are controlled using solenoid valves. The solenoid valves used in this project

are single acting solenoid valves.

The second robot is unusual as this is the first time in years that the participants must

build a four-legged robot. Figure 5 shows this design of the robot which is built using
aluminium profile as a strong body is needed. To build this robot, various designs were

considered. These designs uses various linkage mechanism, for example the Klann linkage
and Jansen linkage [6], to establish a smooth and balanced movement of the robot. The robot

needs a synchronize movement between it legs to ensure its stability. This robot movement
is more or less based on the Plantigrade mechanism adapted from [7]. It has four leg and

each leg has two contact points. It is powered by a worm geared motor which lock its

movement or avoid it from slipping. In this system, the motor is continuously moving in a
direction and the movement angle does not need to be controlled.

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