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Hi,

I am trying to implement a bicycle pedaling motion.

I tried to add a new body with parent body being ground,made a pinjoint and added a single rotational coordinate but unable to link this to the toes and also not able to keep a fixed distance ( radius) from centre.

Any idea or hint would be appreciated,

Nithin

You need to model the crank and the pedals. A pin joint can be the center of your crank body. Then you could have pedal bodies that are also connected to the crank with pin joints and then weld the feet to the pedals, or you could use point constraints to connect the feet to the crank bodies at a point that represents the pedal connection to the foot in the crank frame. The first yields 1 dof of the foot with respect to the crank (about pedal spindle axis- of the pin joint) and the latter has 3 rotational dofs. There are other combinations of joints and constraints you could use to get translation of the foot w.r.t to the pedal like some pedal systems permit.

Hi,

Thanks a lot Ajay for your quick reply.

Its sort of working. I used pin joint for the crank and weldjoint for toes and pedel ( no dof here!! fixed) and finally used a Point constraint to connect the pedal and crank. Hope this is alright.


thanking you again,

Nithin

Why introduce the pedals if you don't want any dof there in the first place? If the foot is effectively welded to the crank are you really expecting the foot to rotate 360 degs and more as the crank goes round? What exactly are you trying to model? If the foot is going around fixed w.r.t. the crank it is not cycling.