Unable to find some datasheet of the geaboxes mounted on ergoCubV1_*

[GiulioRomualdi]

Hi, I was looking for the datasheets of the gearboxes mounted on the ergoCubV1_* model. I found them on this webpage.

I tried to look at the datasheet of the gearboxes online but had some problems finding the datasheet for some joints. Here is a table with the datasheets I found

Joint	Geabox of the documentation	Datasheet
Joint 0 - shoulder pitch	CSD-20-100-2UH	🟢 here
Joint 1 - shoulder roll	CSD-17-100-2A	🟠 I assume is this one even if this model I linked is the CSD-17-100-2A-R while the one in the documentation is CSD-17-100-2A
Joint 2 - shoulder yaw	CSD-17-100-2UH	🟢 here
Joint 3 - elbow	CSD-17-100-2A	🟠 I assume is this one even if this model I linked is the CSD-17-100-2A-R while the one in the documentation is CSD-17-100-2A
Joint 0 - torso roll	CSD-20-100-2UH	🟢 here
Joint 1 - torso pitch	CSD-20-160-2UH	🔴 This gearbox does not seem to exist these are the gearboxes of the family CSD-2UH
Joint 2 - torso yaw	CSD-20-100-2UH	🟢 here
Joint 0 - hip pitch	CSD-25-100-2UH	🟢 here
Joint 1 - hip roll	CSD-20-160-2UH	🔴 This gearbox does not seem to exist these are the gearboxes of the family CSD-2HU
Joint 2 - hip yaw	CSD-20-100-2UH	🟢 here
Joint 3 - knee	CSD-25-100-2UH	🟢 here
Joint 4 - ankle pitch	CSD-25-100-2UH	🟢 here
Joint 5 - ankle roll	CSD-17-160-2A	🔴 This gearbox does not seem to exist these are the gearboxes of the family CSD-2A

Could you help me in finding the missing part? I opened the issue here since there might be a problem with the documentation. Linking the datasheets in the documentation could also be beneficial.

cc @pattacini and @traversaro

[traversaro]

Probably also @fiorisi may know something about this.

[GiulioRomualdi]

With @fabiobergonti we checked the cad and the hip roll torso gearboxes are the one in the table and the info can be found here

On the other hand for CSD-17-160-2A we found this datasheet https://harmonicdrive.de/fileadmin/Downloads/Getriebe_Katalog/Harmonic_Drive_Gears_EN_1053522.pdf and as it can be seen in the picture the gearbox is not available

[GiulioRomualdi]

We also checked the elbow and the shoulder roll CSD-17-100-2A similar to https://github.com/icub-tech-iit/documentation/issues/359#issuecomment-2343262188 the datasheet is here https://harmonicdrive.de/fileadmin/Downloads/Getriebe_Katalog/Harmonic_Drive_Gears_EN_1053522.pdf

So in the end the main problem is related to CSD-17-160-2A which does not exist in the datasheet

[FabioBergonti]

We tried to look for the cad of CSD-17-160-2A in https://harmonicdrive.partcommunity.com/3d-cad-models/csd-2a-harmonic-drive-gear-component-sets-harmonic-drive?info=harmonicdrive%2Fgetriebe_einbausaetze%2Fcsd_2a_asmtab.prj&cwid=6555 but it's not available

[GiulioRomualdi]

with @fabiobergonti we went to the warehouse and we found the harmonic driver. The documentation is correct. The piece exists.

[maggia80]

if you want to have the datasheet, you can contact:

Crisafi Domenico

he should be still the contact person for Harmonic Drive.

[fiorisi]

@GiulioRomualdi I'll write a complete explanation, even if I have seen that you already found some answers.

The website that you are referring to, namely harmonicdrive.net, belongs to the US group Harmonic Drive LLC. For our geographical location we refer instead to Harmonic Drive SE (Germany), which has a different website harmonicdrive.de and sligthly different products.

For example, if I am not mistaken, the product CSD-20-160-2UH can be found on the German catalogue (see page 163).

Can you double check with the German catalogue if there are still differences?

Concerning the series 2A, I think that we didn't include -R because this suffix changes depending on the size of the HD (decision probably taken decades ago).

Finally, for the the part CSD-17-160-2A, this is a special harmonic drive that can not be found on the catalogue.

[GiulioRomualdi]

Thank you! So as far as I understood CSD-17-160-2A has been built ad hoc for us.

[pattacini]

We can close this issue, but I'm available to review PRs to improve the documentation.