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aircraft:tmd:logic

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Logic Circuits

Math

constant

A value that cannot change.

            <[constant][StaticTrue][]
                <[string8][Input][1.0]>
            >

linear

Linear scale and constant offset.

return Input() * Scaling + Offset;
            <[linear][DoubleA][]
                <[string8][Input][A.Output]>
                <[float64][Scaling][1.0]>
                <[string8][Offset][0.0]>
            >

mixlinear

Sum of two values, scaled with a factor. Weights can be negative, to subtract the inputs.

return Input0() * Weight0 + Input1() * Weight1 + Offset;
            <[mixlinear][ABMix][]
                <[string8][Input0][A.Output]>
                <[string8][Input1][B.Output]>
                <[float64][Weight0][1.0]>
                <[float64][Weight1][1.0]>
            >

maximum

Returns the highest value in the list.

            <[maximum][MaximumOfValue0Value1][]
                <[string8][Inputs][ Value0.Output Value1.Output ]>
            >

minimum

Returns the lowest value in the list.

            <[minimum][MinimumOfValue0Value1][]
                <[string8][Inputs][ Value0.Output Value1.Output ]>
            >

absolute

Returns the absolute value of the input, without the sign. Inputs below 0.0 are turned positive.

            <[absolute][Absolute][]
                <[string8][Input][Input.Output]>
            >

sum

Total sum of all inputs.

            <[sum][APlusB][]
                <[string8][Inputs][ A.Output B.Output ]>
            >

product

Multiplies all inputs. Works great to turn off a function under certain conditions, e.g. disable the nose wheel steering.

            <[product][ATimesB][]
                <[string8][Inputs][ A.Output B.Output ]>
            >

inverse

Divides 1.0 with the input. When Input is close to zero the inverse returns 0.0. Normally this function is never needed in the physics computations. If you want to convert units, this can be done in the graphics_input with the Scaling.

            <[inverse][OneOverA][]
                <[string8][Input][A.Output]>
            >

linear_interpolation

Linear interpolations or mappings work by finding an intermediate value from nearby points. The points in the map define discrete points where the output value is know. The map is a list of 2d-vectors. The first component is the input, the second is the output mapped to that input.

The linear_interpolation stops at the last value and does not extrapolate.

            <[linear_interpolation][LinearMapping][]
                <[string8][Input][Control.Output]>
                <[tmvector2d][Map][ (0.0 0.0) (1.0 1.0) ]>
            >

polynomial

Simulates a polynomial function a_n * x^n + … + a_2 * x^2 + a_1 * x + a_0

            <[polynomial][Constant][]
                <[string8][Input][Input.Output]>
                <[float64array][Coefficients][ 1.0 ]>
            >
            <[polynomial][InputDoubled][]
                <[string8][Input][Input.Output]>
                <[float64array][Coefficients][ 2.0 0.0 ]>
            >
            <[polynomial][InputSquared][]
                <[string8][Input][Input.Output]>
                <[float64array][Coefficients][ 1.0 0.0 0.0 ]>
            >
            <[polynomial][InputCubed][]
                <[string8][Input][Input.Output]>
                <[float64array][Coefficients][ 1.0 0.0 0.0 0.0 ]>
            >

clamp

When the value is within a certain range the value itself is returned. When it leaves the range the output stays bounded to the range.

            <[clamp][Clamped][]
                <[string8][Input][Value.Output]>
                <[tmvector2d][Range][ -1.0 1.0 ]>
            >

clamp_cyclic

When the value is within a certain range the value itself is returned. When it leaves the range the output loops back to the start. A good example is the heading on a compass rose that rotates 360° and then loops back to 0.

            <[clamp_cyclic][HeadingDeviation][]
                <[string8][Input][HeadingDeviationSum.Output]>
                <[tmvector2d][Range][ -3.14159 3.14159 ]>
            >

Dynamic Values

integral

differentiator

delay_clamped

first_order_low_pass

Any value to binary

logic_greater

Comparison of the two inputs.

if ( Input0() > Input1() ) return 1.0;
else return 0.0;
            <[logic_greater][Input0GreaterInput1][]
                <[string8][Input0][Input0.Output]>
                <[string8][Input1][Input1.Output]>
            >

logic_range

Determines if an input is within a given range.

if ( Input0() > Range.min && Input0() < Range.max ) return 1.0;
else return 0.0;
            <[logic_range][ValueInRange][]
                <[float64][Input][Value.Output]>
                <[float64][Range][ 0.0 1.0 ]>
            >

Binary operations

logic_invert

Negates the input.

if ( Input0() < 0.5 ) return 1.0;
else return 0.0;
            <[logic_invert][NotA][]
                <[string8][Input][A.Output]>
            >

logic_equal

Returns true (1.0) when the two inputs are equal (difference very small).

            <[logic_equal][AEqualsB][]
                <[string8][Input0][A.Output]>
                <[string8][Input1][B.Output]>
            >

logic_set

Returns true (1.0) when the input is equal to any of the values in the set.

            <[logic_set][LeftMagnetoLeft][]
                <[string8][Input][MagnetosLeft.Output]>
                <[string8][Set][2 3 4]>
            >

logic_and

When all input are true (above 0.5) the logic_and returns 1.0;

            <[logic_and][ABAndC][]
                <[string8][Inputs][ A.Output B.Output C.Output ]>
            >

logic_or

When any input is true (greater 0.5) the logic_or returns true

            <[logic_or][ABOrC][]
                <[string8][Inputs][ A.Output B.Output C.Output ]>
            >

logic_xor

The XOR gate returns 1.0 when the inputs are different (either a true or b true but not both).

if( ( Input0() > 0.5 ) != ( Input1() > 0.5 ) ) return 1.0;
else return 0.0;
            <[logic_xor][ExactlyOneGeneratorOff][]
                <[string8][Input0][LeftGeneratorOff.Output]>
                <[string8][Input1][RightGeneratorOff.Output]>
            >

logic_combination

Some combinations are tricky to evaluate with the elements introduced so far. When complex logic is needed for deciding an outcome, e.g. of a multi-failure mode, the logic_combination can be used to save loads of tmd objects.

            <[logic_combination][ErrorCases][]
                <[string8][Inputs][ A.Output B.Output C.Output ]>
            >

Available combinations are requested with the output functions:

Output Description
OutputNone NOR - 1.0 if all inputs are below 0.5
OutputAny OR - 1.0 if any input above 0.5
OutputAll AND - 1.0 if all inputs above 0.5
OutputCount Number of inputs above 0.5
OutputSingle Exactly one input above 0.5
OutputDual Exactly two inputs above 0.5
OutputTriple Exactly three inputs above 0.5
OutputExclusively0 Only the first input above 0.5
OutputExclusively1 Only the second input above 0.5
OutputExclusively2 Only the third input above 0.5
OutputExclusively3 Only the fourth input above 0.5
OutputExclusively4 Only the fifth input above 0.5
OutputExclusively5 Only the sixth input above 0.5
OutputExclusively6 Only the seventh input above 0.5
OutputExclusively7 Only the eighth input above 0.5

input_active

Returns 1.0 as long as a button is depressed. Returns 0.0 if not. Incoming messages are filtered with the InputValue (see Inputs.

            <[input_active][ButtonDepressed][]
                <[string8][Input][Controls.Button]>
                <[float64][InputValue][1.0]>
            >

variable

Can dynamically be assigned using events.

            <[variable][State][]
                <[string8][Value][0.0]>
            >

state_frozen

Follows the input as long as it is enabled. When InputEnable drops below 0.5 the output value doesn't change.

            <[state_frozen][FollowValueWhenConditionMet][]
                <[string8][Input][Value.Output]>
                <[string8][InputEnable][Condition.Output]>
                <[float64][Value][1.0]>
            >

logic_confirm_delay

Same as logic_greater but with an adjustable time delay.

            <[logic_confirm_delay][FMGC1Powered][]
                <[string8][Input][FMGC1On.Output]>
                <[float64][TimeUp][0.001]>
                <[float64][TimeDown][25.0]>
                <[float64][Threshold][0.5]>
            >

floor

The input is rounded down to the nearest integer.

            <[floor][DiscreteValue][]
                <[string8][Input][DoubleValue.Output]>
                <[string8][Threshold][0.001]>
            >

ceil

The input is rounded up to the nearest integer.

            <[floor][DiscreteValue][]
                <[string8][Input][DoubleValue.Output]>
                <[string8][Threshold][0.001]>
            >

discrete_hysteresis

The input may can be dynamically changing. When the input and the current output state differ by more than the set threshold then the output flips to the input value, rounded to the nearest integer.

An example would be a rotary knob that is turned slowly. The output shall be a discrete integer value. But with the hysteresis small vibrations don't cause the output to flicker back and forth.

            <[discrete_hysteresis][DiscreteValue][]
                <[string8][Input][DoubleValue.Output]>
                <[string8][Threshold][0.7]>
                <[string8][Events][ DEV0.Trigger ]>
            >

flasher_rectangle



state_frozen



aircraft/tmd/logic.1562956589.txt.gz · Last modified: 2019/07/12 20:36 by jh