Contact sensors are body parts that can detect when any other part in the simulation intersects the volume of space. This means it can tell you if there was a contact, but it can not give you any information about the magnitude of the contact force or where it occurred. It is a binary sensor. All you know is that something in the environment intersected with it. Contact sensors do not take participate in the dynamics of the simulation. They have no mass or density so they will not effect the mass distributions of your biomechanical organism. An example of how to use this part is adding it to the surface of a leg in such a way that it extends slightly further than the leg itself. When the leg reaches the ground the contact sensor will touch the ground just before the leg itself. Since the sensor does not deal with collisions it will go through the ground and the leg will stop when the leg itself hits the surface. However, the sensor will be intersecting the ground so it will generate a signal that it has contacted something.
You can use contact sensors as sensory input into your neural network control systems. As I mentioned they are binary, so when they are not contacting a surface they will generate a signal of 0. When they are containing some surface the input value will be the number of surfaces it is contacting. So one way you could detect contacts using this part is to draw a connection from the part to a neuron, and then configure your adapter using a linear gain with a slope of 10 nA. Then when a contact happens 10 nA will be injected into your neuron causing it to depolarize and fire. This could let the network know that this sensor has detected a contact.
You can a make any of the regular parts a contact sensor by clicking the "Sensor" checkbox when adding that part.
This project was supported by: