Question about scaling vs. processing times

[John Olthoff]

So I'm working with a small model (a modification of the rat model in the online library), and the forward simulation often has problems running. The original model and paper describes some muscles as lacking tendons, so I put in very small tendon slack lengths or else the simulation won't run. So 2 questions:

1) Is there a way around the tendon slack length such that I could have tendons in some muscles but not others? Is there a muscle type that doesn't use tendons, and I could use that model for some muscles, and 'normal' Thelen2003 muscles for those with significant tendons?

2) I thought perhaps I could scale the whole model up by a factor of 10 or 100. If I was doing this to approximate a model of how mass vs. force changes across phylogeny, I would scale the mass proportional to the third power (volume of leg sections), but scale the force of the muscles proportional to the second power (proportional to muscle cross section). However, since I want to know the dynamics, this would change that-- so I should scale everything by the same amount. I know this should be obvious, I just want to make sure I'm thinking correctly.

Thanks for any help!

[jimmy d]

You could use the RigidTendonMuscle class.