Ik calculation time varies widely

[robin-gdwl]

Thank you very much for this repo. It helped me a lot in setting up ikfast for my usecase.

I have ran into an issue and would be interested to know wether its normal behaviour or an issue on my end:

The execution time for ik calculations varies widely.
Sometimes it executes in 0.005 seconds sometimes it only takes 0.00003 seconds which is more than 100x faster.
I am always solving the same pose, calculating all solutions without a q_guess pose.

Calculating 100_000 IK solutions usually takes around 10 seconds but sometimes it takes up to 50 seconds.
I was wondering where this discrepancy might come from and if there is anything I can do on my end that can speed up the calculation. Is this a normal range for the execution time?

I am using an M1Pro Macbook.

Thank you very much for any hints.

[cambel]

@robin-gdwl
Hi!,
could you share the scripts you are using for the measurements?

[robin-gdwl]

Here is my test file

import ur_ikfast
import time
import numpy as np

ur5e_arm = ur_ikfast.URKinematics('ur5e')

joint_angles = [-3.1, -1.6, 1.6, -1.6, -1.6, 0.]  # in radians
print("joint angles", joint_angles)

pose_matrix = ur5e_arm.forward(joint_angles, 'matrix')

print("--"*20)
p = time.perf_counter()
ur5e_arm.inverse(pose_matrix, True)
#print("inverse() one from matrix", ur3e_arm.inverse(pose_matrix, True))
print("timer first time: ", time.perf_counter()-p)
print("---")

p = time.perf_counter()
ur5e_arm.inverse(pose_matrix, True)
#print("inverse() one from matrix", ur3e_arm.inverse(pose_matrix, True))
print("timer sec time: ", time.perf_counter()-p)
print("---")

p = time.perf_counter()
ur5e_arm.inverse(pose_matrix, True)
#print("inverse() one from matrix", ur3e_arm.inverse(pose_matrix, True))
print("timer third time: ", time.perf_counter()-p)
print("---")

#Loop
repetitions = 100_000
p = time.perf_counter()
timesum = 0
for i in range(repetitions):
    pi = time.perf_counter()
    sols = ur5e_arm.inverse(pose_matrix, True)
    timesum += time.perf_counter()-pi
#print("inverse() one from matrix", ur3e_arm.inverse(pose_matrix, True))
print("timer loop: ", time.perf_counter()-p)
print("average = ", timesum/repetitions)
#print(sols)
print("---")