Automated Swing Robot 2006 (AVR)
Everyone has played the playground swing since young at a point of time. So our final project will be to design a robot to simulate the swinging motion that brings us lots of joy during our childhood. The robot will extend and retract the leg while sitting on the swing. By using simple physics, the robot will swing on its own from rest to an angle of 90°. There is also an interface such that the robot can be switched to manual mode whereby a volunteer can attempt to it himself.
High Level Design
The Physics
So what is the physics behind the swing? Since not everyone is a physicist, we will attempt to explain the motion using some simple physics. The swing works just like a pendulum, the period is only affected by the length of the rod holding the swing and gravity that we cannot really change. Therefore, we need to find some ways to change the amplitude of the swing arc.
One method to increase the amplitude is to create an addition forward momentum at the top of a swing arc. This can be done by swinging the legs forward when coming down from the top of the arc and retracting the legs backward when backing down from the other end of the arc. Assuming the loss of momentum to drag and friction is less than the momentum added in by the peak of the swing arc, the amplitude will increase with every swing.
The basic concept to increasing the amplitude is resonance. As the swing will be oscillating up and down at a certain frequency, the objective is to impart the external force into the system at the natural frequency. By doing so, the amplitude will increase with every swing.
Link: http://instruct1.cit.cornell.edu/courses/e...l336/index.html
Everyone has played the playground swing since young at a point of time. So our final project will be to design a robot to simulate the swinging motion that brings us lots of joy during our childhood. The robot will extend and retract the leg while sitting on the swing. By using simple physics, the robot will swing on its own from rest to an angle of 90°. There is also an interface such that the robot can be switched to manual mode whereby a volunteer can attempt to it himself.
High Level Design
The Physics
So what is the physics behind the swing? Since not everyone is a physicist, we will attempt to explain the motion using some simple physics. The swing works just like a pendulum, the period is only affected by the length of the rod holding the swing and gravity that we cannot really change. Therefore, we need to find some ways to change the amplitude of the swing arc.
One method to increase the amplitude is to create an addition forward momentum at the top of a swing arc. This can be done by swinging the legs forward when coming down from the top of the arc and retracting the legs backward when backing down from the other end of the arc. Assuming the loss of momentum to drag and friction is less than the momentum added in by the peak of the swing arc, the amplitude will increase with every swing.
The basic concept to increasing the amplitude is resonance. As the swing will be oscillating up and down at a certain frequency, the objective is to impart the external force into the system at the natural frequency. By doing so, the amplitude will increase with every swing.
Link: http://instruct1.cit.cornell.edu/courses/e...l336/index.html