add simple humanoid_benchmark.py and mjcf file

examples/pybullet/examples/humanoid_benchmark.py

@@ -0,0 +1,20 @@
+import pybullet as p
+import time
+p.connect(p.GUI)
+p.setGravity(0,0,-10)
+p.setPhysicsEngineParameter(numSolverIterations=5)
+p.loadMJCF("mjcf/humanoid.xml")
+
+#first let the humanoid fall
+p.setRealTimeSimulation(1)
+time.sleep(3)
+p.setRealTimeSimulation(0)
+
+#now do a benchmark
+print("Starting benchmark")
+logId = p.startStateLogging(p.STATE_LOGGING_PROFILE_TIMINGS,"pybullet_humanoid_timings.json")
+for i in range(1000):
+	p.stepSimulation()
+p.stopStateLogging(logId)
+
+print("ended benchmark")