I’m interested in doing some **type (TBD) of analysis** to simulate the effects, as noted below. I need some “Technical Advice” on how to setup and what type of analysis within Simulation-Premium can be used to evaluate the effect of a person or object falling on top of a structure from a given height, as defined at the start of this email message.

Please read from the beginning and give me some quick technical advice on this subject.

Thanks,

Al James

Principal Mechanical Engineer

Simulation & Validation Testing

Ambient Corporation

7 Wells Avenue, Suite #11

Newton, MA 02459

Ph 617-614-6756

Fax 617-332-0024

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**Personal fall arrest systems must:**

a) Be rigged so that if an employee falls, it is the shortest possible distance so as to minimize the impact and swing of the arrest. The absolute maximum free fall distance is six feet.

b) Limit maximum arresting force on an employee to 1800 pounds with a body harness.

c) Bring the employee to a complete stop and limit maximum deceleration distance to 3.5 feet.

d)**Have sufficient strength to withstand two times the potential impact energy of an employee free-falling a distance of six feet, or the free-fall distance permitted by the system, whichever is used.**

Hello

I did something similar in the past. I had to take into account an impact of 40joules on a component.

By hand I got 40=1/2 m V² .... so for instance a mass of 8Kg at speed of 2.73m/s

Then in sim premium I used a Non Linear Dynamic simulation.

If I remember well one can define an initial velocity to a part. Make sure that mass is correct and that time step is small enough..

then a no penetration contact and that's it...:)

But this kind of computation is veeeery long, and sw simulation is not very efficient with this kind of simulation. It took me ages before getting something correct...many bugs and crashes.

Loïc