Automatic Drawbridge

I built this bridge in order to learn about different types of hinges and linkages. I made two types of bridges with two types of motors. The first bridge is a token drawbridge powered by a VEX EDR motor connected to a pulley, connected to the bridge. It pivots with a filament hinge. The second bridge is not really a drawbridge as it is a four-bar linkage, unlike a normal drawbridge. It isn't very practical but it is cool. 

****For the Normal Bridge print 2 side plates.****

****For the 4Bar print 2 Thin Bars and 2 Bottom Mounts.****

Normal Drawbridge:

Materials:
- M3 Screws and #6-32 screws
- One Vex Motor
- Vex Shaft

Line up the bridge with the matching hinge on the motor mount and slide a piece of 3D-printing filament into the hole and through the other side. You can then cut the filament flush inside of the hole. After this, attach the string to the pulley and place it in the hole at the top of the bridge, place a screw in the hole after placing the string in it to hold it.

4-Bar Bridge:
Materials:
- M3 and M4 Screws
- Mg996r Servo
- Mg996r Servo Horn set (comes with servo)

Steps:
1. Cut one side of the long horn off, resulting in a small arm that has one arm rather than two
2. Lightly screw the Top Bar and the Two Thin Bars in the same way shown in the photo (use the counterbore on the Thin Bars)
3. Mount the horn to one of the thin arms on the side with the counterbore.
4. Mount the servo to the servo mount on one side.
5. Zero your servo and place the bridge in the down position then screw the servo mounts in
6. Take a 5 wide and 2 wide VEX C-channel and attach the interface piece and Bottom Mounts to them
7. Attach the Bottom Ramp piece 
8. Place the bridge along a roughly 1.5ft gap then you are done

***The Bridge can not go more than 90 degrees vertical when lifted.***