Creating a simple bicycle pedal motion I am trying out the various bone constraints in Blender. To further my understanding I am attempting to create the motion of a leg following the pedal of a bicycle. Please refer the image of the simple setup I am attempting.



I have parented the 'Pedal' to the 'Disc' and have animated a rotation of the 'Disc' in the direction of the Blue arrow. 

I am now trying to make the 'Feet' (oops! must be 'Foot') bone to follow the path of the 'Pedal' with an offset. I believe that after achieving this, adding an IK constraint to the 'Feet' bone and affecting all the way to 'Thigh' will give me the necessary motion. However, I am unable to achieve this. I am using Blender 2.7 on Linux. 

Attempting to 'Copy Location' constraint on the 'Feet' object while specifying the target as 'Pedal' does not work.
the bone is connected to its parent which constraint its location also leaving it parented will create some problems when using it as IK terget :


in edit mode select the last bone and remove parent and clear connected




you can use the copy location constraint on the bone now and set it as IK target