The same number as a car driven by a person. The precise number would depend on the make and model of the car.
6
cats
However many the designer wants it to have.
It depends on what kind of robot you are talking about.
In a robot there is a joint where ever you put a motor that will move the metal/plastic "bones" of the robot so you can have as many joints as you like. Source: My Brain
Entertainment robots apparently have 7 flexible joints.
9000
50
4
P. Th. L. M. van Woerkom has written: 'Accuracy of modal frequency set with fictitious joints modelling' -- subject- s -: Flexible bodies, Joints, Modal response, Manipulators 'On fictitious joints modelling of manipulator link flexibility for the HERA simulation facility pilot' -- subject- s -: Joints, Hermes manned spaceplane, Manipulators 'Synthesis of local control for a robotic manipulator joint' -- subject- s -: Actuators, Joints, Robotic manipulators 'Equivalent flexibility modelling for the recursive simulation of robot manipulator dynamics' -- subject- s -: Flexible bodies, Many body problem, Manipulators 'Quasi-recursive dynamics equations for spacecraft-based flexible robotic manipulators' -- subject- s -: Flexible bodies, Many body problem, Dynamic models, Manipulators
they help you move your arms,legs,etc. Joints overall help something become more flexible and enhance movement. If you ever see an old 60's or 70's scifi movie with a robot that moves with it's legs you may notice that it is slow, and legs aren't as flexible as they would with joints. That is the beauty of joints, but however there is a price. As many elderly would say, there joints would experience a type of pain. It is possible that joints tend to wither and become "achy" over time. Still, joints are helpful because they promote flexiblity, faster movement, and easier transport.
Many bones have many joints, hence, great flexibility.
The Complete Robot has 688 pages.