robotic arm presentation
TRANSCRIPT
We Have an Idea
Build an arm that:
● mimics human motion
● is controlled by human motion
● is programmable
Welcome to the Drawing Board
● Designed in Autodesk Inventor
● Functioning elbow joint
● Improvements easily applied
Speed
With the same input speed● Gears with more teeth (bigger) rotates proportionally slower because it takes more
teeth/rotation● Gears with less teeth (smaller)rotates proportionally faster because it takes less
teeth/rotation
Therefore● Speed in*Teeth in=Speed out*Teeth out or● Speed in*(Teeth in/Teeth out)=Speed out or● Speed in/(Teeth out/Teeth in)=Speed out or● Speed in/Gear reduction=Speed out
(“Teeth out/Teeth in” is gear reduction)
Torque
Torque=Force*Distance so Torque in=Force in*Distance in orForce in=Torque
in/Distance inForce in is exerted on the gear out teeth soTorque out=Force in*Distance out orTorque out=(Torque in/Distance in)*Distance out orTorque out =Torque in*(Distance out/Distance in) orTorque out =Torque in*(Teeth out/Teeth in) orTorque out =Torque in*Gear reduction
(distance is radius)(radius is proportional to teeth)
What is a motor?
A machine, especially one powered by electricity or internal combustion, that supplies motive power to a vehicle or a device with moving parts.
Motor Strength
● Motor strength comes from the motor’s rotation speed and torque
● Depending on operating voltage, the stall torque can either be 25.5 kg x cm or 31.6kg x cm
● What this shows is how much weight a motor can hold when it isn’t rotating
Our Motors
● The motor we selected has the strongest stalltorque within our budget.● The resolution will help the arm mimic actions
precisely● The motors will be light enough to attach to
the arm without weighing it down
Introducing the Omni Wheel
● Rotate like normal wheels● Smaller wheels roll
perpendicular to rotational axis
● Two degrees of freedom