Differences

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--- eeros_architecture:control_system:blocks [2015/10/14 14:42] – [Signals] graf
+++ eeros_architecture:control_system:blocks [2022/04/19 12:36] (current) – [Predefined Blocks] ursgraf
@@ Line 3: / Line 3: @@
 ===== Inputs and Outputs =====
-Every output carries a signal. An input simply refers to a connected output.
+Every output carries a [[eeros_architecture:control_system:signals|signal]]. An input can be connected to an output and simply refers to the signal of this connected output.
-{{ inoutputuml.png?500 | //Input und Output Type//}}
+[{{ block.png?200 | //Two blocks connected together//}}]
 This makes sure that each input is connected to a single output. On the other hand, an output can carry its signal to many inputs.
 =====Predefined Blocks=====
 Build your control system by instantiating all the necessary blocks. For example:
-<code c>
+<code cpp>
   Step<> step(0.0, -3.14159265359, 5);
   step.setName("step 1");
-  step.getOut().getSignal().setName("phi_desired");
   Sum<3> sum;
   sum.setName("adds feedback");
-  sum.getOut().getSignal().setName("control signal");
   sum.getIn(0).connect(step.getOut());
-  Gain<> posController(174.5); // kp=174.5
+  Gain<Vector2> posController(174.5); // kp=174.5
-  posController.getOut().getSignal().setName("phi_d_set");
+  posController.setName("gain block for position control");
 </code>
 Each block has inputs and/or outputs. Name the output in a meaningful way and assign a physical unit to each of the outputs. The signals which  connect the different blocks will be created automatically. \\
@@ Line 27: / Line 25: @@
 Output signals are created together with the blocks. On the other side, there is no need to generate and name input signals.
+For most blocks you have to specify the signal types on its inputs or outputs with template parameters, see [[tools:cplusplus#templates|]]
-=====Signals=====
-The signals used to connect the blocks can be of different types. Currently the following types are supported
-  * Real signals
-  * Logic signals
-All signals are vectors of dimension 1...n. Each signal can be assigned a name and a unit. All dimensions of a signal share the same name and unit.\\
-As an example we look at a block which does summation. Two signals, each of dimension 3, will be added together.
-<code c>
-	Sum sum(3);
-	sum.getOut().setName("phi");
-	sum.getOut().setUnit("rad");
-</code>
-This is shown in the following diagram:
-{{ sumblock.png?300 | //Summation block with threedimensional signals//}}
-The functions //getIn()// and //getOut()// return an input or output signal, respectively. With the summation block, //getOut()// returns the single output signal. //getIn()// returns the first input signal. This is the same as //getIn(0)//. To obtain the second input signal you have to write //getIn(1)//.
-In order to access the individual dimensions of a certain signal, use functions like
-<code c>
-	sum.getOut().getValue();  // returns dimension 0 of output
-	sum.getOut().getValue(0);  // returns dimension 0 of output
-	sum.getOut().getValue(2);  // returns dimension 2 of output
-	sum.getIn(1).getValue(2);  // returns dimension 2 of input 1
-</code>
 =====Making Connections=====
 When all necessary blocks have been created the blocks must be wired together.
-<code c>
+<code cpp>
-	sum.getIn(0).connect(step.getOut());
+  sum.getIn(0).connect(step.getOut());
-	sum.getIn(1).connect(enc.getOut());
+  sum.getIn(1).connect(gain.getOut());
-	posController.getIn().connect(sum.getOut());
+  posController.getIn().connect(sum.getOut());
 </code>
+//getIn(0)// returns the first input signal. With //getIn(1)// you will get the second input signal.
+===== Initial State of Outputs =====
+All outputs of any block carry a value of NaN (not a number) after the block has been created. Only after the first execution of its run-method does the signal have a meaningful value.