Computer Guided Trebuchet Seth Katz Matt Leese

Overview  Trebuchet is a medieval siege weapon Throws a projectile by utilizing a counterweighted arm  Computer control provides automated accurate targeting

System Overview  Trebuchet  Embedded Controller  Computer Trebuchet Embedded Controller Computer

Trebuchet Overview Pivot Arm SlingProjectile Count er Weigh t

Trebuchet Targeting  Targeting Range Azimuth  Range Governed by: Move counterweight for range  Azimuth Rotate trebuchet base

Trebuchet Specifications  Fire a Nerf Ball (~2 oz.) a distance of 15 ft.  Therefore: Counterweight of 12.5 lbs. Small Arm Length of 2.5 in. Long Arm Length of 12.5 in.

Actuators  Rotate trebuchet base DC motor connected to gearing  Move counterweight DC motor connected to a lead screw  Remove firing pin Servomotor connected to the firing pin

Trebuchet Design

Trebuchet Design (2)

Embedded Controller  MC68HC12  Provides control over trebuchet Input data from sensors Output data to actuators  Takes commands from Computer Sent desired azimuth and counter-weight location Sent fire command

Embedded Controller Block Diagram Embedded Controller Pivot Sensor Pivot Actuator Counterweight Actuator Counterweight Sensor Release Actuator Computer

 Windows GUI Program to select desired target  Calculates appropriate azimuth and counter-weight position  Commands Embedded Controller to move trebuchet  Commands Embedded Controller to fire

GUI Screenshot

Schedule

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