Page 116 - Robot Design Handbook ROBOCON Malaysia 2019

will be moved up and clamped by an arm. When the MR1 is at the Throwing Zone, the arm

will be lifted up and the Shagai will be shot by a pneumatic piston.

The MR1 does not have the ability to move in diagonal line since we are using
normal wheel instead of omni or mecanum wheel. Even though we are using normal wheels,

with a 24V supply, speed is found to be faster since the MR1 is able to reach the Khangai

area within 16 seconds. The passing of the Gerege took about 22 seconds which are
considered fast enough for a normal wheel.

2.1.1 Mechanical Design

the MR1 is used to carry the Gerege and pass it to the MR2. For the holding

mechanism, we used pneumatic cylinder to hold the Gerege higher than the MR1 body. The

hole on the Gerege is inserted to a shaft which is installed on the arm that is connected to
the pneumatic piston. For the lifting of Shagai, we used the concept of a forklift. Instead of

using pneumatic power source, we proposed a simple solution which uses a rope and pulley.
We attached the rope to the lift and through the pulley, the rope is tied to the motor shaft.

When the motor is rotating, the rope will roll to the shaft and pull the lift up along with the
Shagai. After the maximum height is reached, Shagai will be pushed by a metal plate behind

it. The metal plate is welded to a nut which is inserted to the pneumatic piston. To get enough

force to shoot the Shagai, the pressure needs to be high enough. If a big diameter cylinder
is used, the movement is too slow. So a medium diameter cylinder that can take up pressure

up to 600kPa was used. Our the MR1 is fully manual, controlled by an experienced operator
who keeps practising every day. Since we are using two wheels, we can only gain speed by

using relatively high voltage and an experienced operator who knows when to speed up,
turn and stop.

Servo motor is used at the top part of the MR1. The servo motor is used to hold the

Gerege from falling from its position. A bracket is installed to the servo motor to follow the
flow of the motor. During setting time, the bracket is 90 degrees in front of the Gerege.

During the movement of the MR1, the bracket stays in the same position until the passing
time whereby during passing time the bracket is opened by changing the direction of the

servo motor. There are three power window motors that are used in the MR1. Two of those

motors are used for the movement of the MR1 as in moving forward, backward, turning left
and right. These two motors, as shown in Figure 1, are located at each side of the MR1, that

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