Page 144 - Robot Design Handbook ROBOCON Malaysia 2019

Leg design

Figure 7: MR2 Mechanical design

This design is built with six degrees of freedom (6DOF) so that the robot is able to
move more flexibily and its legs can lift vertically. This will allow it to jet up and down

when passing through the obstacles, thus increases its stability. The motion of the robots is
like a spider. The support point is used so that the normal force exerted from the ground will

enable the weight of the robot to be balanced by the support point and the servo motor

instead of the servo motor only. The linkage is built by 3D printer and it is screwed at the
both side of the leg to avoid the leg to bending while moving and it also provides a stable

support for the robots. The bottom of the legs is wrapped with sponge to increase fraction

toward the ground. This design is built using aluminium because it is light, thus decreases
the current consume by the servo motor. Due to the material on the body the electrical

component and lifting mechanism are placed evenly on the body so as to distribute the force
equally among the layer.

2.1 Electronic Design

For electronic design, we use printed circuit board (PCB). With the use of PCB, we

are able to reduce the mess on our electronic component and to ensure the ease of
maintanence. For electronic system, we use Arduino Mega as our main controller, raspberry

pi for the usage of ROS and custom-made-pic-based controller board for IMU purposes.
The Arduino Mega 2560 is designed to be in the middle of the board to allow the

components and pin headers to connect to the Arduino Mega 2560 easily. The width of the
wire on the PCB is 32 except for the wires connected to the power source which is 100. This

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