Summary of all neuron types 

The most recent set of neurons and their documentation can be found in the application itself.
In GUI, go to Parameters → Genetics → Neurons to add and hover the mouse over the neuron name.

N   (Neuron)

Standard neuron

 
   supports any number of inputs
   provides output value
   does not require location in body

Properties:
   Inertia (in) float 0..1 (default 0.8)
   Force (fo) float 0..999 (default 0.04)
   Sigmoid (si) float -99999..99999 (default 2)
   State (s) float -1..1 (default 0)

G   (Gyroscope)

Tilt sensor.
Signal is proportional to sin(angle) = most sensitive in horizontal orientation.
0=the stick is horizontal
+1/–1=the stick is vertical

 
   does not use inputs
   provides output value
   should be located on a Joint

Gpart   (Part Gyroscope)

Tilt sensor. Signal is directly proportional to the tilt angle.
0=the part X axis is horizontal
+1/–1=the axis is vertical

 
   does not use inputs
   provides output value
   should be located on a Part

Properties:
   rotation.y (ry) float -6.282..6.282 (default 0)
   rotation.z (rz) float -6.282..6.282 (default 0)

T   (Touch)

Touch and proximity sensor (Tcontact and Tproximity combined)
–1=no contact
0=just touching
>0=pressing, value depends on the force applied (not implemented in ODE mode)

 
   does not use inputs
   provides output value
   should be located on a Part

Properties:
   Range (r) float 0..1 (default 1)
   rotation.y (ry) float -6.282..6.282 (default 0)
   rotation.z (rz) float -6.282..6.282 (default 0)

Tcontact   (Touch contact)

Touch sensor.
–1=no contact
0=the Part is touching the obstacle
>0=pressing, value depends on the force applied (not implemented in ODE mode)

 
   does not use inputs
   provides output value
   should be located on a Part

Tproximity   (Touch proximity)

Proximity sensor detecting obstacles along the X axis.
–1=distance is "r" or more
0=zero distance

 
   does not use inputs
   provides output value
   should be located on a Part

Properties:
   Range (r) float 0..1 (default 1)
   rotation.y (ry) float -6.282..6.282 (default 0)
   rotation.z (rz) float -6.282..6.282 (default 0)

S   (Smell)

Smell sensor. Aggregated "smell of energy" experienced from all energy objects (creatures and food pieces).
Close objects have bigger influence than the distant ones: for each energy source, its partial feeling is proportional to its energy/(distance^2)

 
   does not use inputs
   provides output value
   should be located on a Part

*   (Constant)

Constant value

 
   does not use inputs
   provides output value
   does not require location in body

|   (Bend muscle) 

   uses single input
   does not provide output value
   should be located on a Joint

Properties:
   power (p) float 0.01..1 (default 0.25)
   bending range (r) float 0..1 (default 1)

@   (Rotation muscle) 

   uses single input
   does not provide output value
   should be located on a Joint

Properties:
   power (p) float 0.01..1 (default 1)

M   (Muscle for solids) 

   uses single input
   does not provide output value
   should be located on a Joint

Properties:
   power (p) float 0.01..1 (default 1)
   axis (a) integer 0..1 (default 0)

D   (Differentiate)

Calculate the difference between the current and previous input value. Multiple inputs are aggregated with respect to their weights

 
   supports any number of inputs
   provides output value
   does not require location in body

Water   (Water detector)

Output signal:
0=on or above water surface
1=under water (deeper than 1)
0..1=in the transient area just below water surface

 
   does not use inputs
   provides output value
   should be located on a Part

Energy   (Energy level)

The current energy level divided by the initial energy level.
Usually falls from initial 1.0 down to 0.0 and then the creature dies. It can rise above 1.0 if enough food is ingested

 
   does not use inputs
   provides output value
   does not require location in body

Ch   (Channelize)

Combines all input signals into a single multichannel output; Note: ChSel and ChMux are the only neurons which support multiple channels. Other neurons discard everything except the first channel.

 
   supports any number of inputs
   provides output value
   does not require location in body

ChMux   (Channel multiplexer)

Outputs the selected channel from the second (multichannel) input. The first input is used as the selector value (–1=select first channel, .., 1=last channel)

 
   uses 2 inputs
   provides output value
   does not require location in body

ChSel   (Channel selector)

Outputs a single channel (selected by the "ch" parameter) from multichannel input

 
   uses single input
   provides output value
   does not require location in body

Properties:
   channel (ch) integer

Rnd   (Random noise)

Generates random noise (subsequent random values in the range of –1..+1)

 
   does not use inputs
   provides output value
   does not require location in body

Sin   (Sinus generator)

Output frequency = f0+input

 
   uses single input
   provides output value
   does not require location in body

Properties:
   base frequency (f0) float -1..1 (default 0.0628319)
   time (t) float 0..6.28319 (default 0)

Delay   (Delay) 

   supports any number of inputs
   provides output value
   does not require location in body

Properties:
   delay time (in steps) (t) integer 1..1000 (default 1)

Light   (Light) 

   supports any number of inputs
   does not provide output value
   should be located on a Part

Properties:
    (flavor) float 0..4 (default 0)

Nn   (Noisy neuron)

Propagates weighted inputs onto the output, but occasionally generates a random value

 
   supports any number of inputs
   provides output value
   does not require location in body

Properties:
   Error rate (e) float 0..0.1

SeeLight   (Light receptor) 

   does not use inputs
   provides output value
   should be located on a Part

Properties:
    (flavor) float 0..4 (default 0)

SeeLight2   (Light receptor 2)

Returns the average signal intensity of all nearby transmitters. Unlike "SeeLight", signals do not attenuate over distance (however, the maximal signal distance is limited by the "range" parameter).

 
   does not use inputs
   provides output value
   should be located on a Part

Properties:
    (range) float 0..100 (default 10)

S0   (Smell group 0)

Detects only energy from group #0

 
   does not use inputs
   provides output value
   should be located on a Part

S1   (Smell group 1)

Detects only energy from group #1 (in many experiments group #1 contains food)

 
   does not use inputs
   provides output value
   should be located on a Part

Thr   (Threshold)

if (input>=t) then output=hi else output=lo

 
   supports any number of inputs
   provides output value
   does not require location in body

Properties:
   Threshold (t) float
   Low output value (lo) float
   High output value (hi) float

Experimental neurons

Do not use unless you know what you are doing. Some of these neurons may be unstable, many are used for special purposes.

Nu   (Unipolar neuron [EXPERIMENTAL!])

Works like standard neuron (N) but the output value is scaled to 0...+1 instead of –1...+1.
Having 0 as one of the saturation states should help in "gate circuits", where input signal is passed through or blocked depending on the other singal.

 
   supports any number of inputs
   provides output value
   does not require location in body

Properties:
   Inertia (in) float 0..1 (default 0.8)
   Force (fo) float 0..999 (default 0.04)
   Sigmoid (si) float -99999..99999 (default 2)
   State (s) float -1..1 (default 0)

Fuzzy   (Fuzzy system [EXPERIMENTAL!])

Refer to publications to learn more about this neuron.

 
   supports any number of inputs
   provides output value
   does not require location in body

Properties:
   number of fuzzy sets (ns) integer
   number of rules (nr) integer
   fuzzy sets (fs) string (default "")
   fuzzy rules (fr) string (default "")

VEye   (Vector Eye [EXPERIMENTAL!])

Refer to publications to learn more about this neuron.

 
   uses single input
   provides output value
   should be located on a Part

Properties:
   target.x (tx) float
   target.y (ty) float
   target.z (tz) float
   target shape (ts) string (default "")
   perspective (p) float 0.1..10 (default 1)
   scale (s) float 0.1..100 (default 1)
   show hidden lines (h) integer 0..1 (default 0)
   output lines count (each line needs four channels) (o) integer 0..99 (default 0)
   debug (d) integer 0..1 (default 0)

VMotor   (Visual–Motor Cortex [EXPERIMENTAL!])

Must be connected to the VEye and properly set up. Refer to publications to learn more about this neuron.

 
   supports any number of inputs
   provides output value
   does not require location in body

Properties:
   number of basic features (noIF) integer
   number of degrees of freedom (noDim) integer
   parameters (params) string

Sti   (Sticky [EXPERIMENTAL!]) 

   uses single input
   does not provide output value
   should be located on a Part

LMu   (Linear muscle [EXPERIMENTAL!]) 

   uses single input
   does not provide output value
   should be located on a Joint

Properties:
   power (p) float 0.01..1 (default 1)

PIDP   (PID Positional [EXPERIMENTAL!])

PID Regulator (positional/full value form)

 
   uses single input
   provides output value
   does not require location in body

Properties:
   K (k) float 0.01..100
   Ti (ti) float 0.01..100
   Td (td) float 0.01..100

PIDV   (PID Velocity [EXPERIMENTAL!])

PID Regulator (velocity/incremental form)

 
   uses single input
   provides output value
   does not require location in body

Properties:
   K (k) float 0.01..100
   Ti (ti) float 0.01..100
   Td (td) float 0.01..100