manual for the movable bridge - instructables
TRANSCRIPT
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 1
Manual for the Movable Bridge
VG100 Introduction to Engineering
Fall 2019
Members: 陈志远 Chen Zhiyuan 519021910194
苏振漩 Su Zhenxuan 519370910158
邓旨健 Den Zhijian 519021910239
王者 Wang Zhe 519021910104
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 2
Table of Contents
Ⅰ. Introduction
Background Information…………………………………………………………………………3
Course ＆ Project Information....................................................................................................4
Ⅱ. Concept Diagram
Concept Diagram…………………………………………………………………………………5
Ⅲ. Material list
Materials………………………………………………………………………………………...6
List………………………………………………………………………………………………7
Ⅳ. Step-by-step Process
Step 1. Component Fabrication…………………………………………………………………..9
Step 2. The Assembling Process……………………………………………………………...…12
Step 3. The realization of Deployment and Retraction…………………………………………..13
Step 4. Circuit Diagram…………………………………………………………………………14
Step 5. Final System View………………………………………………………………………14
Ⅴ. Appendix
Video Links……………………………………………………………………………………..16
Arduino Codes…………………………………………………………………………………..16
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 3
Ⅰ. Introduction
-Background information
Our team is MaJIc6 with four members
(Figure 1.1), from University of Michigan-
Shanghai Jiao Tong University Joint Institute
(UM-SJTU JI), which locates in the campus
of Shanghai Jiao Tong University in
Minhang District, Shanghai, China (Figure
1.2). Joint Institute is a prestigious
engineering college, which provides students
with great educational resources and
combines the advantages of western
education and eastern education. Figure 1.1 Team Members
Figure 1.2 Campus of SJTU
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 4
-Course ＆ Project information
VG100 Introduction to Engineering is a special curriculum of Joint Institute which
emphasizes on cultivating students’ technical and communication skills on engineering.
The Movable Bridge is our project one for 2019 fall semester which requires us to
design and construct a bridge made of balsa wood, which can be deployed and retracted
over two abutments automatically and is able to hold a load of a certain weight.
Game Rules ＆ Regulations:
1. The length of the bridge should be within 700mm and 750mm and the width
should be within 160mm and 200mm.
2. A car with the size of 90mm in width and 20mm in height can be fully placed
on all parts of the bridge.
3. The bridge should be able to fit in a box with the size 350 * 350 * 250mm
before the deployment process and after the retraction process.
4. The deployment and retraction process should be both within 1 minute.
5. The bridge should be able to hold a load of more than 1kg or 3.33times of its
own weight.
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 5
Ⅱ. Concept Diagram
Figure 2.1 Concept Diagram-Deployed View
Figure 2.2 Concept Diagram-Retracted View
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 6
Ⅲ. Material List
-Materials
1 2 3
4 5 6
7 8 9
10 11 12
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 7
13
Figure 3 Material List
-list
No. Item Quantity Price Hyperlink
1 Balsa Wood Board
500*200*5mm
500*200*5mm
3
1
66RMB
(9.3USD)
https://item.taobao.com/item.htm?spm
=a1z09.2.0.0.42dc2e8dw9G99B&id=
25881864914&_u=h
2 Balsa Wood Stick
8*8*500mm
10*10*500mm
12
12
38RMB
(5.4USD)
https://item.taobao.com/item.htm?spm
=a1z09.2.0.0.67002e8dYqUlW5&id=
534712185104&_u=h2aedbh93eea
3 Screw and Nut Set 1 16RMB
(2.3USD)
https://detail.tmall.com/item.htm?id=5
60051299394&spm=a1z09.2.0.0.6700
2e8dYqUlW5&_u=h2aedbh90d66&sk
uId=4106783951640
4 Arduino Uno R3 1 138RMB
(19.4USD)
https://item.taobao.com/item.htm?spm
=a1z09.2.0.0.6e3c2e8djuc6B5&id=58
4520048971&_u=l2aedbh946e4
5 L298N RC Servo
Motor Driver
Module
1 12.8RMB
(1.8USD)
https://item.taobao.com/item.htm?spm
=a1z09.2.0.0.6e3c2e8djuc6B5&id=52
1519133959&_u=l2aedbh94008
6 SG90
9g
3 29.7RMB
(4.2USD)
https://item.taobao.com/item.htm?spm
=a1z09.2.0.0.6e3c2e8djuc6B5&id=52
1409261817&_u=l2aedbh95bf4
7 Nanfu Battery 5 16.9RMB
(2.4USD)
https://detail.tmall.com/item.htm?spm
=a230r.1.14.30.65e164d9AaX6pw&id
=40569984581&ns=1&abbucket=10
8 DuPont Line
300mm
3 23.4RMB
(3.3USD)
https://item.taobao.com/item.htm?spm
=a1z09.2.0.0.6e3c2e8djuc6B5&id=52
7015353868&_u=l2aedbh91ca7
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 8
9 Breadboard 1 9.9RMB
(1.4USD)
https://item.taobao.com/item.htm?spm
=a1z09.2.0.0.6e3c2e8djuc6B5&id=52
1386704489&_u=l2aedbh93c63
10 Nylon Cord 1 5.5RMB
(0.8USD)
https://m.tb.cn/h.eLA7fqB?sm=93bab
5
11 DC Reduction 1 1.2RMB
(0.2USD)
https://m.tb.cn/h.epH0TbE?sm=83fe3
1
12 12V Battery Box 3 3RMB
(0.4USD)
https://m.tb.cn/h.epHY9ug?sm=e8538
8
13 Tacks Box 1 4,9RMB
(0.7USD)
https://c.tb.cn/h.eKjy9KS?sm=02f328
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 9
Ⅳ. Step-by-step Process
-Step 1: Component Fabrication
A. Building Part 1
1. Place four upright wood sticks(60*8*8mm) on the four corners of the
board(330*16*5mm).
2. Place another two sticks with the same size in the middle of the long sides of
the board.
3. Stick two beams(330*8*8mm) on the top of the upright sticks.
4. Connect the beams with three sticks(144*8*8mm), two on the edge of the
beams and one in the middle.
5. Select two slant sticks between each two upright sticks.
6. Stick a small stick (40*8*8mm) at the end of Part 1. The function of the st ick
is to prevent Part 1 from sliding out. Then Part 1 is finished. (See Figure 4.1)
B. Building Part 2
1. Get a stick(10*10*25mm), a plastic bottle gap(d=3mm), and a pushpin. (See
Figure 4.2)
Figure 4.1 The final view of part 1
Figure 4.2 Roller components
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 10
2. Drill on the center of the gap.
3. Drill on the stick, 2mm from bottom on the central line.
4. Connect them. (See Figure 4.3)
5. Repeat the 4 steps above 5 times. Then paste 6 rollers on the bottom board.
6. Place six rollers on a board (325*20*5mm), three on each side. The use of the
rollers is to reduce the friction between the two wood boards.
7. Place four upright sticks (147*8*8mm) on the four corners of the wood board.
8. Place another two sticks with the same size in the middle of each long side of
the board.
9. Stick two beams (325*8*8mm) on the top of the upright sticks to stabilize them.
10. Connect the beams with four sticks (184*8*8mm), two on the edge of the
beams and two on the middle.
11. Stick two slant sticks between each corner stick and middle stick.
12. Stick one stick (317*10*10mm) on each inner side of the frame.
13. Stick one stick (45*8*8mm) on each front end of the stick in step 7.
14. Stick two sticks (184*10*10mm) stuck together on bottom of the sticks in step
8.
15. Stick two sticks (184*8*8mm) stuck together on the front opening of the frame,
117mm from the bottom.
16. Stick one stick (184*10*10mm) between two beams, 63mm from the front
opening.
17. Stick one stick (43*8*8mm) on each side of the stick in step 11, 10mm from
Figure 4.3 View of rollers
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 11
the edge.
18. Fix an axle between two sticks (55*10*10mm). Then fix them between the
stick in step 11 and the front opening, on the central line.
19. Stick the wood board (180*78*2mm) on the top of the frame, with one side
stuck on the top of the sticks in step 3, and the other side stuck on the bottom
of the stick on the after end of the frame.
20. Stick four sticks (24*10*10mm) on the corners of a wood board (70*70*5mm).
21. Stick the sticks in step 15 on the outer bottom of the frame, 61mm from the
front opening.
22. Stick servo1 on the back of stick in step 10. Then Part 2 is finished. (See Figure
4.4, Figure 4.5)
C. Building Part 3
1. Get a wood board (305*200*5mm).
2. Stick two pins on two front corners of the board.
3. Fix a pulley on the top of a stick (335*10*10mm).
Figure 4.4 The final view of Part 2
Figure 4.5 The side view of Part 2
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 12
4. Stick the pole in step 3 on the board, 80mm from the afterbody end, on the
central line.
5. Fix two sticks to stabilize the pole.
6. Fix two sticks (40*10*10mm) stuck together on the board, lying against the
back of the pole.
7. Fix the motor on the sticks in step 6, with one side stuck on the pole.
8. Fix a stick(70*8*8mm) to servo2. (See Figure 4.6)
9. Fix servo2 on the board, 11mm from the after-end edge, 15mm form the right
edge.
10. Symmetrically do step 8,9 with servo3. Then Part 3 is finished. (See Figure 4.7)
-Step 2: The Assembling Process
1. Connect a nylon string (d=1mm) with the back of Part 1. The string should be
long enough. (about 2m)
2. Pull the string over the axle in Part 2, then over the pulley in Part 3.
Figure 4.7 The final view of part 3
Figure 4.6 The servo with wood stick
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 13
3. Insert Part 1 into Part 2 from the front opening.
4. Wind the line to the motor.
5. Stick the rear end of Part 2 with the pins in Part 3.
6. Connect wires as Circuit Diagram. (See Circuit Diagram)
7. The assembling process of the whole system is finished. (See Figure 4.8)
-Step 3: The Realization of Deployment and Retraction
A. Deployment
1. Servo2 and servo3 rotate 0.1°/s simultaneously for 80s. Motor rotates
anticlockwise to loosen the string in the meanwhile.
2. Motor keeps rotating for 13s. The bridge is then laid flat by gravity.
3. Motor rotates in opposite direction for 15s to fasten the string, pulling out Part1.
4. Motor rotates anticlockwise for 2s to loosen the string, ensuring Part 1 is laid
on the abutment.
5. The deployment process ends.
B. Retraction
1. Motor rotates clockwise for 25s, pulling the bridge upright.
2. Part 1 is now slant and blocked.
3. Motor begins rotating to loosen the string.
4. Servo1 rotates 30°/s clockwise for 2.5s to pull Part 1 upright.
5. Servo1 rotates 90°/s anticlockwise to its origin position.
Figure 4.8 The whole system
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 14
6. Motor continues rotating anticlockwise to loosen the string for 15s. Part 1
slowly declines.
7. The retraction process ends.
-Step 4: Circuit Diagram
-Step 5: Final System View
Figure 4.9 Circuit Diagram
Figure 4.10 Final view of the bridge when retracted
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 15
Figure 4.11 Side view of the bridge when retracted
Figure 4.12 Final view of the bridge when deployed
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 16
Ⅴ. Appendix
A. Video Link:
https://v.youku.com/v_show/id_XNDQwOTA2Mzg5Mg==.html?spm=a2h3j.8428
770.3416059.1
B. Arduino Codes:
#include<Servo.h>
Servo servo1, servo2, servo3;
char screen_in;
int pos_of_servo1, pos_of_servo2, pos_of_servo3;
int motor[3][3];
void setup() {
servo1.attach(5);
servo2.attach(6);
servo3.attach(3);
motor[1][0] = 7;
motor[1][1] = 8;
for (int i = 1; i <= 2; i++) {
pinMode(motor[i][0], OUTPUT);
pinMode(motor[i][1], OUTPUT);
}
Figure 4.13 Side view of the bridge when deployed
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 17
Serial.begin(9600);
}
int m_move(int i) {
digitalWrite(motor[i][0], LOW);
digitalWrite(motor[i][1], HIGH);
}
int m_antimove(int i) {
digitalWrite(motor[i][0], HIGH);
digitalWrite(motor[i][1], LOW);
}
int m_stop(int i) {
digitalWrite(motor[i][0], LOW);
digitalWrite(motor[i][1], LOW);
}
int deploy() {
servo1.write(pos_of_servo1 = 18);
servo2.write(pos_of_servo2 = 96);
m_antimove(1);
for (int i = 1; i <= 80; i++) {
pos_of_servo1++;
pos_of_servo2--;
servo1.write(pos_of_servo1);
servo2.write(pos_of_servo2);
delay(100);
}
//delay(16000);
delay(13000);
m_stop(1);
m_move(1);
//delay(23000);
delay(15000);
m_stop(1);
m_antimove(1);
delay(2000);
m_stop(1);
return 0;
}
int retract() {
Instructors:
Dr. Shane Johnson
Dr. Irene Wei
Page 18
servo1.write(pos_of_servo1 = 98);
servo2.write(pos_of_servo2 = 16);
m_move(1);
delay(25000);
m_stop(1);
m_antimove(1);
for (pos_of_servo3 = 105; pos_of_servo3 >= 30; pos_of_servo3--) {
servo3.write(pos_of_servo3);
delay(30);
}
for (pos_of_servo3 = 30; pos_of_servo3 <= 105; pos_of_servo3++) {
servo3.write(pos_of_servo3);
delay(10);
}
delay(15000);
m_stop(1);
}
void loop() {
char OPT;
if (pos_of_servo1 < 90) {
servo1.write(pos_of_servo1 = 18);
servo2.write(pos_of_servo2 = 96);
servo3.write(pos_of_servo3 = 105);
}
OPT = Serial.read();
if (OPT == 'D') {
Serial.println('D');
deploy();
while (1) {
OPT = Serial.read();
if (OPT == 'R') {
break;
}
}
retract();
while (1);
}
}