steering_controllers_library: Add reduce_wheel_speed_until_steering_reached parameter

[christophfroehlich]

Some features are missing in the library to feature-equally integrate the older tricycle_controller (#850).

reduce_wheel_speed_until_steering_reached is one step closer.

The old code

ros2_controllers/tricycle_controller/src/tricycle_controller.cpp

Lines 173 to 189 in 97c1e24

	// Reduce wheel speed until the target angle has been reached
	double alpha_delta = abs(alpha_write - alpha_read);
	double scale;
	if (alpha_delta < M_PI / 6)
	{
	scale = 1;
	}
	else if (alpha_delta > M_PI_2)
	{
	scale = 0.01;
	}
	else
	{
	// TODO(anyone): find the best function, e.g convex power functions
	scale = cos(alpha_delta);
	}
	Ws_write *= scale;

I modified the function a bit to be continuously differentiable

This breaks ABI of the odometry class, but I don't think that lots of people use this directly without the derived controllers.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.49%. Comparing base (97c1e24) to head (4a35d46).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1314      +/-   ##
==========================================
+ Coverage   80.34%   80.49%   +0.14%     
==========================================
  Files         105      105              
  Lines        9384     9454      +70     
  Branches      826      832       +6     
==========================================
+ Hits         7540     7610      +70     
  Misses       1570     1570              
  Partials      274      274              

Flag	Coverage Δ
unittests	80.49% <100.00%> (+0.14%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...steering_controllers_library/steering_odometry.hpp	100.00% <ø> (ø)
...llers_library/src/steering_controllers_library.cpp	79.63% <100.00%> (+0.09%)	⬆️
...ring_controllers_library/src/steering_odometry.cpp	82.42% <100.00%> (+1.01%)	⬆️
...ontrollers_library/test/test_steering_odometry.cpp	100.00% <100.00%> (ø)

... and 2 files with indirect coverage changes