Introduction: Deployable Bridge

We are group Pigeon from University of Michigan-Shanghai Jiao Tong University Joint Institute (UM-SJTU JI). Located in Min Hang district, JI is one of the most brilliant colleges in Shanghai Jiao Tong University. With abundant teaching resources and advanced facilities, students are able to enjoy better development in JI.

Step 1: Introduction and Game Description

ŸCourse & Project Information

VG100 Introduction to Engineering is a course of great importance in JI. The course teaches students knowledge of how to be an engineer and cultivates students’ practical and innovation ability. For 2019 fall semester, the Project 1 of VG100 is the Movable Bridge. We are required to design and make a bridge that is deployable and retractable.


1. Only balsa wood and Elmer’s wood glue are allowed as components when constructing the bridge’s structure. Other materials are only allowed for the construction electrical devices.

2.Cables are allowed. But they will be loosed compulsively when performing the Load Test.

3.The length of the bridge should be no less than 700mm, otherwise it can’t be placed on the abutments. The distance between the two abutments can be turned longer if needed.


1. First, we put the bridge on the scale and weigh the bridge.

2. Then we fix the bridge in the retracted form on one side of the abutment, using several nails.

3. The bridge will be put in a box and take the size test.

4. After that, the bridge should deploy automatically in 60 seconds and retract automatically in 60 seconds.

5. After the retraction, the bridge should be put in the box again and take the size test.

6. Then, the cable (if there exists one) should be snipped off and the bridge can be deployed by hand lying on both sides of the abutment and take the load test.

Step 2: Material List

Step 3: Concept Diagram

Step 4: Circuit Diagram

Step 5: Preparation Beforehand

Learn abort Arduino

1 Download the software (Arduino IDE)

2 Refer to when programming or learning to program

Step 6: Component Fabrication

A. Constructing the Bridge Floor

1. Cut out one piece of balsa wood with the length of 35cm and the width of 10cm

2. Cut out another piece of balsa wood with the length of 44cm and the width of 10 cm

3. Cut out 6 pieces of wooden slats with the length of 180cm and the width of 1cm.

4. Stick the wooden slats and two pieces of balsa wood together.

Constructing the Connecting Part of the Bridge

1. Cut out a piece of wooden slat with the length of 35.5cm and the width of 1cm.

2. Cut two small pieces of wooden slat with the length of 3cm and the width of 1cm from the slat in 1. This will form a new piece of slat.

3. Cut out another piece of wooden slat with the length of 44.5cm and the width of cm. The piece should be fixed perfectly to the new piece in 2.

4. Connect the two pieces of slat in 2 and 3 together, using a needle that goes through the middle of the two pieces.

Constructing the Overall Structure of the Bridge

1. Follow the drawing to build the left and the right side of the bridge. Use sticks to connect the left and the tight part from above the bridge.

2. Stick the connecting part to the Bridge Floor conducted in A.

3. Stick the two side parts to the Bridge Floor. Remember that the connecting part and the two side parts should be stuck firmly.

4. Test the Connecting Part to see whether it is effective.

Fixing the controlling system.

1. Fix the engine on the sticks across the Bridge Board.

2. Fix the controlling system on the two upright sticks on the each side of the bridge.