Final Competition
Group B
22rd, May, 2007
Outline
• Competition Rules
• Expected Performance
• Strategy
• Mechanic Design
• Program
Competition Rules
Blocks
3 minutesAuto
Restart
Collide Main Role
Make full use of these
Expected Performance
• Improve the latency: reduce the time for taking
each block;
• Improve the throughput : increase the capacity
of blocks;
• Design several strategies to make choice
when collision and restart occurs;
• Improve the accuracy of turn and avoid using
parameters: make use of sensors.
Original Strategy
Different routes: left, mid, right routes;
Foresee whether the block is still there and
change strategy dynamically;
Calculate the points machine got and make
decision;
Try to go straight to save time.
Practical Strategy
Different routes: left, mid, right routes;
Set restart route and scan route;
Improve the ability of follow line even for some
extreme situations which will reduce the speed;
Consider the placement of blocks;
Give up the use of ultrasonic sensor since the
field is small and no need of dynamic strategy.
Mechanic Design
• Simply with efficient performance;
• Sensor: 3+2;
• Wheels: gear choice, two wheels;
• Arms: gear choice;
• Bumper Switch;
• Fencing structure: dimension, fence the blocks
inside.
Sensor Placement
Closing the sensors will increase the sensitivity!
Front Detection
Relativity of Sensors and
Wheels
Distance
between
sensors and
wheels
should be big
enough for
sensitivity.
Gear Choice of Back
Wheels
3:2 Gear Choice
based on the
required speed of
wheels
Motor
Front Wheels
Using
flexible front
wheels to
reduce the
error of turn!
Gear Choice of Front Arm
Servo
1:1 Gear Choice
based on the
range of Servo
Gear Choice of Back Arm
Servo
2:1 Gear Choice
based on the
range of Servo
Bumper Switch
Four
Selective
Choices for
different
strategies
and restart
Fencing Structure
Keep the
blocks inside
Depth 220mm
With the arm,
expected
performance:
three blocks
Width 140mm
large enough for
the dimension of
block
Program
• Follow Line (3 trace sensors);
• Turn Left and Right (2 detective sensors );
• Game Field Map (x,y,dx,dy);
• Execute the arms work
Follow Line and Turn
Front Detection
Line Tracer
Build Field Map in Program
X
Y
(0,0) (1,0) (2,0)(-1,0)(-2,0)
(1,0)
(2,0)
(3,0)
(4,0)
(5,0)
Arm Works and the
Placement of Blocks
Expected Performance
• Improve the latency: fast to take blocks;
• Improve the throughput : maximum four blocks;
• Design several strategies to make choice
when collision and restart occurs;
• Improve the accuracy of turn and avoid using
parameters: make use of sensors.
Final Competition
Appreciate the Study of
VEX in ENGG395E