Page 310 - Robot Design Handbook ROBOCON Malaysia 2019

2.1.2 Mechanical Design of the MR2

Figure 3 shows the kinematic diagram and the physical appearance and embodiment
of the proposed design of the MR2.

Figure 3: The MR2 mechanical design

As can be seen in Figure 3, the robot is designed with a combination of two robotic
design types; the robotic arm and quadruped legged robot. The robot has 14 degrees of

freedoms (DOFs) overall where 2 DOFs at the arm and 12 DOFs at each legs. The robotic
arm has an ability to pick up and manipulate objects at a distance while quadruped legged

provides locomotion to the robot. The number that is indicated at each joint symbol

represents the ID of each servo motor.

The Dynamixel AX-12A actuator from Robotis is used as the rotating joints of the robot.
The servo motor is one of the most affordable entry-level smart servo motor for robotics

with advanced feed-back functions such as temperature, speed, voltage, shaft position and

load [3]. All the servo management and position control is handled by the servo’s built in
micro-controller. Another special features of this servo actuator is that it has the capability

to operate in endless rotation mode thus, making it suitable to build a wheel type robot using
dc motor. Table 2 shows some hardware specification of Dinamixels AX-12A servo motor.

2.2 Electronic Design

2.2.1 Electronic Design for the MR1

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