Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: drinu on April 04, 2013, 02:26:45 PM

Title: Actuator force required
Post by: drinu on April 04, 2013, 02:26:45 PM

Hi,

I am planning to build a robotic arm which will make use of actuators to lift the linkages. Now I have to questions:

1) Is the use of actuators a good idea?

2) With reference to the diagram attached, what are the approximate forces requires by actuator 1 and 2 to lift a load of approx 8 to 10kg? (8 to 10kg include the weight of two motors which will be placed at the far end. They will be used to rotate the load)

Any kind of help would be really appreciated.

Title: Re: Actuator force required
Post by: drinu on April 04, 2013, 06:27:14 PM

Note on diagram:

*The red lines indicate the actuators (actuator 1 is used as third class lever, actuator 2 is used as first class lever)
*Pivot 2 is the base pivot and pivot 1 is the elbow pivot
*The green line represents the base/surface

Title: Re: Actuator force required
Post by: Gertlex on April 05, 2013, 09:57:08 AM

Note that 'actuator' refers to any method of movement, whether it's linear actuators, motors, servos, musclewire, etc.  It looks like you are talking about linear actuators.

The second diagram nicely conveys what your setup would be.  To calculate the forces the linear actuators will exert, you will need to calculate the torques that your 'Load' exerts at pivots 1 and 2.  However, to do that, you will need to specify the lengths of the linear actuators, and determine at what angles you're calculating the load at.  It should be reasonably straight forward to set up a series of equations which you plug in lengths/angles/positions to, and get the loads on the linear actuators at various positions.