Question about get_object_position

Support
1

Hi,

i was trying to study poppy and have a question about balance behavior. In vrep robot Module there is a attribute called get_object_position and also we could input get_object_position(‘head_visual’). But it isn’t working in real poppy. I guess it needs Camera for eyes. Has anyone know the reason and what could be my problem? tell me how should i do?

2

Hi,
get_object_position refer to the V-REP api to get any object position in the simulated scene. To have the same feature in real poppy, you should have a forward kinematics model of the robot, which does not exist for now…
@Thot and @Manon are working on it.

3

Thanks for your answer. And we can infer that, balance behavior couldn’t be used in real poppy. Then how can we keep balance in real poppy?

4

You can’t unless if you add an IMU!

5

I wrote a mistake. It is possible to do it with forward kinematics only on the vector space of the robot. If the vector space of the robot and the vector space of the scene are not the same, you have to use an external sensor to track the robot (like optitrack or kinect).
As Nicolas says, an IMU is the only embedded solution to make a balance behaviour.

6

You can test what is possible to do with V-REP and get_object_position but for the real poppy as already said, you have to add an IMU to know the position
thot is working on it : RAZOR IMU interface for Pypot

7

Thank you for your answer. I want to test the razor imu from your Link. but it said, couldn’t import razor, although I have input the definition of the razor above. it means, i should first install the poppy-walk package and then the mean code in python input? sorry, i’m neu and nun studying.

8

The work about the IMU is still in progress. I have never test it. Sure @Thot could explain better than me. What I understood :
_ You have to plug and install the razor IMU on your poppy (have you done it without difficulties ?)
_ You have to add the IMU library (in fact razor.py) from Thot github : https://github.com/HumaRobotics/poppy-walk/blob/thomas/razor/razor.py

And I think it should work. Can you show your code ?