Implement modifiable PD gains with datastore call

[rohanpsingh]

Hi @gergondet

I wanted to implement a datastore call to be able to set the PD gains for all joints from within any mc-rtc controller. Right now I'm doing works well with what is shown in the patch below.

Since later I want to implement the same call (with the exact same signature) in mc-openrtm too,
I would like to know your suggestions on whether this is the best way to implement it.

How to call

``` // set new pd gains bool mod_servo_success = false; if(ctl.datastore().has("set_pdgains::" + ctl.robot().name())) { mod_servo_success = ctl.datastore().call("set_pdgains::" + ctl.robot().name(), kp, kd); } if (!mod_servo_success) { mc_rtc::log::warning("[{}] Could not set PD gains through datastore call!!!", name()); } ```

[gergondet]

Hi Rohan,

I think it's fine, some remarks:

• I think you'd also want a way to read the gains
• maybe similar functions for reading/setting individual gains (i.e. for one joint, not setting P or D individually)
• I would reverse the name and switch to CamelCase i.e. robot().name() + "::SetPDGains"
• the implementation of the call should print a message if there is an error with the parameters (i.e. size of kp or size of kd is wrong) to save time in case of issues.

[rohanpsingh]

Thanks for the remarks! I implemented each of the points you mentioned :)