Unable to grasp needle, proximity not detected

[kschwan]

Hi @adnanmunawar,
I'm revisiting Task 2 (needle grasping and driving) as we have some students wanting to use the simulated environment in a project. I'm experiencing some issues however:

Even though the tool is placed in a "good" pose, I'm unable to grasp the needle (it is not detected by the "proximity sensor" and thus not attached to the tool). I notice that only one object is listed in /ambf/env/psm2/Sensor0/State/sensed_objects at any one time. Almost always it's Phantom when close to the needle (lying on the phantom).

Below is a small video to help show the problem (motions look jerky but that's because of poor video recording).

I interface with the simulator via launch_crtk_interface.py and I have set add_joint_errors=False.

I use 314a4ba and WPI-AIM/ambf@18637b4.

Screencast.from.2023-03-01.15.56.40.webm

[adnanmunawar]

Hi Kim,
Thanks for opening the issue and the nice video (it's always great to see what's going on). Can you try this:
When the simulation launches, with any of the simulator's window selected, press "s" and/or "a" to toggle the visibility of "sensors" and "actuators" respectively. The sensor is visualized as a green and red sphere. These denote the start and end of the line segment for the ray tracing proximity sensor. When the sensor detects an object in its segment, a pink sphere is show at the surface of detection. This should show us whether or not the sensor is detecting the needle, visually. Here is short video of it that I recorded.

[kschwan]

Thanks Adnan,
Sorry for my late reply. I'm currently on a temporary leave from work and haven't tried the above yet, but I will :)

[Wilboy-ai]

Hi Adnan,

(I work together with Kim)

I still experience some grasping problems. I have tried toggling on the visibility of the sensor and It looks like the sensor ray is too short to detect objects at the very tip of the gripper (I have included a video). Is this correct? I would expect the end of the sensor ray to be at the tip of the gripper.

grasping_problems.webm

I have also experienced the ray sensor extend beyond the gripper tip in cases where the suture phantom is detected. (I have included a video)

extended_ray.webm

(I have tried extending the ray length to be at the tip of the gripper which helped)

I hope you can help, thanks :)