diff --git a/data/Base_1.urdf b/data/Base_1.urdf
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diff --git a/data/Base_2.urdf b/data/Base_2.urdf
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diff --git a/data/Pendulum_Tendon_1_Cart_Rail.urdf b/data/Pendulum_Tendon_1_Cart_Rail.urdf
new file mode 100644
index 000000000..a680987a5
--- /dev/null
+++ b/data/Pendulum_Tendon_1_Cart_Rail.urdf
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diff --git a/examples/pybullet/examples/inverted_pendulum_tendon_actuation.py b/examples/pybullet/examples/inverted_pendulum_tendon_actuation.py
new file mode 100644
index 000000000..d9b075931
--- /dev/null
+++ b/examples/pybullet/examples/inverted_pendulum_tendon_actuation.py
@@ -0,0 +1,167 @@
+"""
+https://valerolab.org/
+
+PID control of an inverted pendulum actuated by strings.
+"""
+
+import pybullet as p
+import time
+import math as m
+import numpy as np
+import pybullet_data
+import matplotlib.pyplot as plt
+
+
+p.connect(p.GUI)
+plane = p.loadURDF("plane.urdf")
+
+"""_____________________________________________________________________________________________________________________________"""
+"""Gains, motor forces, daq and timing parameters"""
+
+""" Gains for pendulum angle"""
+proportional_gain = 30000
+integral_gain = 18000
+derivative_gain = 22000
+
+"""Motor force parameters"""
+tension_force = 600
+
+"""Control input parameters"""
+u_factor = 1.5
+u_lower_limit = tension_force
+u_upper_limit=9000
+
+"""Data aquisition, timing and history"""
+time_steps = 2000
+history = np.array( [[1000,-1000,0]] )
+time_history = np.array([[0]])
+previous_pendulum_angle = 0
+previous_cart_position = 0
+
+"""_____________________________________________________________________________________________________________________________"""
+"""Loading URDF files"""
+
+cubeStartPos = [-2.15,0,.75]
+cubeStartPos2 = [0,0,1.4]
+cubeStartPos3 = [2.15,0,.75]
+
+PulleyStartOrientation = p.getQuaternionFromEuler([1.570796, 0, 0])
+cubeStartOrientation = p.getQuaternionFromEuler([0,0,0])
+cubeStartOrientation2 = p.getQuaternionFromEuler([0,-1.570796,0])
+
+base_1 = p.loadURDF("Base_1.urdf",cubeStartPos3, cubeStartOrientation, useFixedBase=1, flags=p.URDF_USE_SELF_COLLISION) #Base 1: magenta base and tendon
+base_2 = p.loadURDF("Base_2.urdf",cubeStartPos, cubeStartOrientation, useFixedBase=1, flags=p.URDF_USE_SELF_COLLISION) #Base 2: white base and tendon
+pendulum = p.loadURDF("Pendulum_Tendon_1_Cart_Rail.urdf",cubeStartPos2, cubeStartOrientation2, useFixedBase=1, flags=p.URDF_USE_SELF_COLLISION)
+
+
+"""_____________________________________________________________________________________________________________________________"""
+"""Getting access and information from specific joints in each body (each body has links and joint described in the URDF files):"""
+nJoints = p.getNumJoints(base_1) #Base 1: magenta base and tendon
+jointNameToId = {}
+for i in range(nJoints):
+ jointInfo = p.getJointInfo(base_1, i)
+ jointNameToId[jointInfo[1].decode('UTF-8')] = jointInfo[0]
+Base_pulley_1 = jointNameToId['Base_pulley1']
+
+nJoints = p.getNumJoints(pendulum)
+jointNameToId = {}
+for i in range(nJoints):
+ jointInfo = p.getJointInfo(pendulum, i)
+ jointNameToId[jointInfo[1].decode('UTF-8')] = jointInfo[0]
+last_tendon_link_1 = jointNameToId['tendon1_13_tendon1_14']
+cart_pendulumAxis = jointNameToId['cart_pendulumAxis']
+cart = jointNameToId['slider_cart']
+
+nJoints = p.getNumJoints(base_2) #Base 2: white base and tendon
+jointNameToId = {}
+for i in range(nJoints):
+ jointInfo = p.getJointInfo(base_2, i)
+ jointNameToId[jointInfo[1].decode('UTF-8')] = jointInfo[0]
+last_tendon_link_2 = jointNameToId['tendon1_13_tendon1_14']
+Base_pulley_2 = jointNameToId['Base_pulley1']
+"""_____________________________________________________________________________________________________________________________"""
+"""Creating new contraints (joints), with the information obtained in the previous step"""
+
+pulley_1_tendon_magenta = p.createConstraint(base_1, Base_pulley_1, pendulum, last_tendon_link_1, p.JOINT_FIXED, [0, 0, 1], [0, 0, 0], [-.56, 0, 0])
+tendon_white_cart = p.createConstraint(base_2, last_tendon_link_2, pendulum, cart, p.JOINT_FIXED, [0, 0, 1], [0, 0, 0], [0,-.55, 0])
+
+"""_____________________________________________________________________________________________________________________________"""
+"""Defining some motor conditions"""
+p.setJointMotorControl2(pendulum, cart_pendulumAxis, p.VELOCITY_CONTROL, targetVelocity=0, force=0)
+p.setJointMotorControl2(base_1, Base_pulley_1, p.VELOCITY_CONTROL, targetVelocity=10, force=1000) #Base 1: magenta base and tendon
+p.setJointMotorControl2(base_2, Base_pulley_2, p.VELOCITY_CONTROL, targetVelocity=10, force=-1000)#Base 2: white base and tendon
+
+
+"""_____________________________________________________________________________________________________________________________"""
+
+
+p.setGravity(0,0,-10)
+
+
+for i in range (time_steps):
+ p.stepSimulation()
+ pendulum_angle = p.getJointState(pendulum,cart_pendulumAxis)
+ pendulum_angle = pendulum_angle[0]
+ angle_delta_error = -pendulum_angle
+
+ #PROPPORTIONAL
+ p_correction = proportional_gain * pendulum_angle
+
+ #INTEGRAL
+ i_correction = integral_gain * (previous_pendulum_angle + pendulum_angle)
+ previous_pendulum_angle = pendulum_angle
+
+ #DERIVATIVE
+ d_correction = derivative_gain * angle_delta_error
+
+ u = p_correction + i_correction + d_correction + 10
+
+ u = abs(u)
+ if uu_upper_limit:
+ u=u_upper_limit
+
+ if pendulum_angle > 0:
+ u_pulley_1 = u * u_factor #Base 1: magenta base and tendon
+ u_pulley_2 = -tension_force #Base 2: white base and tendon
+ #print(">0")
+ else:
+ u_pulley_1 = tension_force #Base 1: magenta base and tendon
+ u_pulley_2 = -u * u_factor #Base 2: white base and tendon
+ #print("<0")
+
+ p.setJointMotorControl2(base_1, Base_pulley_1, p.VELOCITY_CONTROL, targetVelocity=100, force = u_pulley_1)
+ p.setJointMotorControl2(base_2, Base_pulley_2, p.VELOCITY_CONTROL, targetVelocity=100, force = u_pulley_2)
+
+ history = np.append(history , [[ u_pulley_1, u_pulley_2, pendulum_angle]] , axis = 0)
+
+ time.sleep(1./240.)
+
+print("Done with simulation")
+
+fig, ax1 = plt.subplots()
+ax1.set_xlabel("Time Steps")
+ax1.set_ylabel("Activation Values")
+ax1.plot(history[:,0],label="u_pulley_1")
+ax1.plot(history[:,1],label="u_pulley_2")
+ax1.set_ylim((-12000,12000))
+
+plt.legend(loc='best', bbox_to_anchor=(0.5, 0., 0.5, 0.5),
+ ncol=1, mode=None, borderaxespad=0.)
+plt.title("Ctrl Input and Angle History")
+plt.grid(True)
+color = 'tab:red'
+ax2 = ax1.twinx()
+ax2.set_ylabel('Pendulum Angle', color=color)
+ax2.plot(np.rad2deg(history[:,2]),label="Angle",color=color)
+ax2.tick_params(axis='y', labelcolor=color)
+ax2.set_ylim((-90,90))
+
+fig.tight_layout()
+plt.show()
+
+p.disconnect()
+
+
+