Some question about the code to calculate the velocity #7
+1,389
−85
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
intergrated urdf model from francesco to the controller of dane. renamed some phantom omni stuff to geomagic (not all) added a few parameters in the launch file
added a hint for zero joint values
rviz won't display the robot model if the parameter pointing to geomagic_description/urdf/omni.urdf is missing. RobotModel will throw the error: "Parameter [Geomagic_robot_description] does not exist, and was not found by searchParam()".
Add parameter "Geomagic_robot_description" from headless to rviz launch
|
This was many years ago so I can't really say for sure. But based on the code comments it looks like maybe I was applying a low-pass filter to clean up the velocity signal (attenuate signal >20hz), and using a 2nd order backwards differential estimation, since directly estimating velocity from a series of high-frequency position signals is pretty noisy. By the way, this repo is unmaintained so if you have suggested improvements you should probably fork it. Thanks :) |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
vel_buff = (omni_state->position * 3 - 4 * omni_state->pos_hist1
+ omni_state->pos_hist2) / 0.002; //mm/s, 2nd order backward dif
omni_state->velocity = (.2196 * (vel_buff + omni_state->inp_vel3)
+ .6588 * (omni_state->inp_vel1 + omni_state->inp_vel2)) / 1000.0
- (-2.7488 * omni_state->out_vel1 + 2.5282 * omni_state->out_vel2
- 0.7776 * omni_state->out_vel3); //cutoff freq of 20 Hz
The code above to calculate the velocity, I'm confused about what that means? can you tell me something about that?