Page 56 - Robot Design Handbook ROBOCON Malaysia 2019

2.2 Messenger Robot 2

Figure 5: Overview of the MR2

2.2.1 Mechanical Design

As shown in Figure 5, the MR2 is an eight DOF automatic quadruped (spider) robot
that uses the Arduino control board. The dimension of the MR2 is 0.4 m (L) x 0.4 m (H) x

0.4 m (W) with a weight of 2.2 kg, which fulfills the basic requirement. The overall
mechanical structure of the MR2 is made of aluminium, which provides a minimum weight

for the movement. The front part of the MR2 is equipped with a sensor. The spider robot is

able to move on uneven terrain and flat surface. Four symmetric position of the legs allow
the robot to tackle transition of surface at any angle [1]. In terms of locomotion, the MR2

provides flexibility and adaptability to encounter the surface of the game field. There are a
total of nine TowerPro MG996R servos used in this robot due to its good performance [2]

and price consideration. Each of them is for front right hip, front right leg, back right hip,
back right leg, back left hip, back right leg, front left hip, front left leg and the Gerege holder.

The Gerege holder is designed in such a way that a large surface area is created for the ease

of receiving. A frictionless acrylic base allows the Gerege to slide along the path, down to
the aluminium-based Gerege holder that is controlled by one servo motor. The Gerege will

then be raised using a servo motor when the MR2 reaches Uukhai Zone.

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