popi-mkx3
commented
4 years ago Hi Fernando,
Thanks for your feedback!
No, our motors are not brushless but brushed.
But this is not the best solution. We prefer to present you our errors and what we get out of them :
What we have done ;
-
A fairly heavy and oversized structure (22.5kg without actuators) due to the imposed raw materials (aluminum and steel), the time that we lacked to simulate (oversizing), and our lack of experience.
-
An underestimated weight constraint in the choice of actuators. The power to weight ratio being very very important in this area.
-
Over-sizing of the initial torque requirement.
-
Underestimate the problem of EMI (electromagnetic interference), which is stronger in brushed motors and which caused us a lot of noise problems at the end of the project.
This led us to choose heavy brushed motors with a high torque (120Nm) which essentially serves to compensate for the weight of the actuators themselves (48kg of actuators).
What should rather be done;
Take BLDCs that have a better power-to-weight ratio and fewer EMI problems. Ideally brushless like those used for drones, like T-motors for example, which are very light.
We are currently designing the Popi V2, our actuators now weigh less than 500 grams compared to the average 4kg for those of the V1. Also, we are now using much lighter materials for the structure (mostly 3D-printed). These developments should allow us afterwards to have a new Popi of only 20kg maximum.
Do not hesitate if you have any question, we will answer with pleasure.
Looking forward to reading you,
POPI Team
Le sam. 16 mai 2020 à 20:54, Fernando Caponetto notifications@github.com a écrit :
Hi! First, I would say that your project is very interesting!
I am curious about the kind of motors you have been using in this project. Are you currently using BLDC motors?
Thanks in andance
— You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub https://github.com/popi-mkx3/popi_project/issues/2, or unsubscribe https://github.com/notifications/unsubscribe-auth/AO4URXIXHUHEVR7Q5CRRMUTRR3OP3ANCNFSM4NDBBCLQ .
Hi! First, I would say that your project is very interesting!
I am curious about the kind of motors you have been using in this project. Are you currently using BLDC motors?
Thanks in andance