Introduction: LVJZ Naval Battle for UM-JI VG100
We are Team 14, LVJZ, for the Vg100 Course of the UM-JI (Figure 1, 2) . The UM-SJTU Joint Institute, located in Min Hang campus of Shanghai Jiaotong University, Shanghai, China, is an institute with advanced teaching methods which trains our ability of collaboration and enriches our knowledge. Every year, freshmen have a project made with their teammates and compete with other teams. This semester, our robot attended the "Naval battle” competition and reached the semi-finals.
LVJZ Members (Figure 3,4,5) :
About the Competition:
The competition,”Naval battle”, is an imitation of the battleships shooting at opponents. Students design their own robots to move the cannon balls, which are represented by Ping-Pong balls and Wooden balls in the game, to the enemy’s territory. The higher the score you get, the more possible you would win.
Competitions are divided into two part. The first is the individual game, students should move the ball as soon as possible. And the second part is the dual match, the highest 8 groups will be selected out to against each other.
For the game field, it is a 2000mm*1500mm rectangular area with a 70mm height and 18mm width wall in the middle, and the wall leaves a gap of 50mm from the ground. (Figure 6,7)
The main idea of the game is to improve students’ problem-solving ability and make students understand how robots work.
• Time limit: 3 minutes
• Totally 4 Wooden balls (diameter of 70mm) and 8 Ping-Pong balls (diameter of
40mm.) in each side.
• Size limit for robots: 350mm*350mm*200mm
• Only the DC Motor provided by JI are available, while the servo motor are not included.
• The robots are allowed to transform into a bigger size when the competition begins.
• The ranking will be determined by the following order
- Total score
- The number of the large balls on the opposite side
- The remaining time
• If two teams are of the same ranking, an additional 1-minute match will be held.
• The score will be counted at the end of the game
- If the balls fall on the opponent’s territory, the small, large ball counts as 1,4 points
- For any ball fall on under the wall in the middle of their own territory, the ball counts as 0 point
- If the ball is knocked out of the field by one of the team, deduction of 2,5 points will be made on the team’s total score for each small, large ball.
Size: 35cm*35cm*20cm(length, width, height)
Engine: Gear motor JGA25-370 DC12V 170RPM
Our score on Game day is 24 and time left is 30 seconds (Figure 8).
Our place in the tournament results is top 4 out of 22 teams (Figure 9).
Concept Diagram & Exploed View:
You can refer to the concept diagram (Figure 10), robots in the exploded view(Figure 11) and fabricated prototype (Figure 12).
Following are the functions of components,
① Metal Gripper is used to pick up the ball.
② Servo motor is to turn the Metal Gripper into the wanted direction.
③ Arduino Mega2560 is programmed to control the motors and deal with the signal from ps2.
④ Customized Acrylic Board is the platform to hold and assemble the component.
⑤ Omni-wheel is to regulate the direction of the car.
⑥ Lithium-ion Polymer Battery is to provide the robot with energy.
⑦ Wheels, undoubtedly, are for easier moving.
⑧ Bearings are to connect the wheel, motors and the customized Acrylic board
⑨ Motors are to drive the wheels.
⑩ PS2 Joystick is to send the signal to control the robot.
⑪ PS2 receiver is to incept signal from PS2 Joystick and then send them to the Arduino Mega2560.
- Motor*2 (JGA25-370 DC12V 170RPM)
0 RMB($0.00USD) Provided by JI
- Wheel*2, radius 7.0cm+ bearing*2
0 RMB($0.00USD) Provided by JI
- Omni-wheel*1(2 inches)
- Customized Acrylic Board
- Arduino Mega 2560*1
- Motor Driver Panel*1
- PS2 Joystick*1+ receiver*1+ 3A Battery*2
38 RMB ($3.01USD)https://goo.gl/Dh6D6G
- DuPont Line*40 (20cm)
- Servo Motor*3 (LD-2015*1, LDX-335MG*2)+Connectors
96 RMB($3.01USD) https://goo.gl/KpUfre
- Metal Gripper*1(127mm*230mm)
85 RMB($12.81USD) https://goo.gl/KpUfre
- Lithium-ion Polymer Battery*2 (11.1v, 2200mah)+ T head Wire*2
- Lithium-ion Polymer Battery Charger*1(11.1v, 20W)
35 RMB($5.27USD) https://goo.gl/t5cSnc
Step 1: Circuit Diagram
Step 2: Component Fabrication
Figure out the length and width of the acrylic board we needed and plan the number of holes on it to assemble into the car in advance. The outline of the acrylic boards are shown in the picture. Apart from the main board, there are two additional boards which are used to mount the manipulator and to balance the robot respectively.
1. Draw the main board outline by using software the CorelDraw.
2. Output as CDR/ DWG file and insert it into the laser cutter.
3. Cut your acrylic board by the laser cutter.
Note: You may send your file to plastic product company which can be found in Taobao to customise acrylic board. For the thickness of acrylic boards, 3mm is prefere.
Step 3: Assemble the Mechanical Paw
Fix the pieces of iron with 9 bows of copper and 3 sets of nuts and bolts to combine the mechanical paw like the one in the first picture.
The left half of the mechanical claw is fastened to the steering gear with a set of large screws and nuts, and the gear in the bottom is meshed with the right half of the gear.
Fix the right half of the mechanical claw on the steering gear with four sets of screws and nuts.
Step 4: Connect the First and Second Steering Gear
- Use four sets of screw nuts to connect the L-shaped bracket to the shell of the first steering gear
- Then use four sets of screw nuts to connect the second steering gear to the L-shaped bracket
Step 5: Connect the Second and Third Steering Gear
- Use eight sets of screws and nuts on both ends of the u-shaped iron stand to be fixed with the second steering gear, as shown in the first picture.
- Connect the base of the u-shaped stand with four sets of screws and nuts to an L-shaped bracket.
- Use four sets of screws and nuts on the other side of the L-shaped bracket on the side of the third steering gear.
Step 6: Connect the Whole Mechanical Arm to the Acrylic Board
- Use four sets of screw nuts to connect the U-shaped bracket to the acrylic board.
- Use four sets of screw nuts to connect the U-shaped bracket to the third steering gear on both sides.
- Use four sets of screw nuts to secure the small acrylic board onto the base plate
Step 7: Fit on Omni-wheel
- Align the four holes in the omni-wheel with the four holes in the front of the acrylic board, and fix them with four sets of screws and nuts.
Step 8: Mounting the Motors and Tires on the Acrylic Board
- Use four sets of screw nuts to fix the bracket to the bottom of the base plate.
- Use two screw nuts to connect the motor to the other side of the bracket.
- Connect the hexagonal copper column with the motor with two screws.
- Plug the copper plunger into the tire hole then screw in a fixed tire on the outside with a screw.
Note: Using impropriate length of screws may block the movement of motors.
Step 9: Connect Circuit
Plase refer to the circuit diagram in Step 2
- Weld the four wires with the motor's interface and pass the four wires through the pre-punched hole
- Insert four wires into the interface of the motor board and tighten the screws to fix the wire
- Connect the red line of the aero-mode battery to the positive pole of the Arduino plate, and the black line receives the negative pole
- Connect the six ports of the motor board to the corresponding port of the Arduino board, and use 4 sets of copper columns, screw and nut to hold the motor board with the Arduino board.
Step 10: Programming
- Program the robot with Arduino IDE
Step 11: Let's Try Your Robot!!!!
The final views of the robot.