[Python] remove extra coordinate

I have a program simulating the movement of a ball inside a box, and tracking it using matplotlib:

def track_bouncing_charge():
fig, (ax, ax_dist) = plt.subplots(1, 2, figsize=(14, 6))
ax = fig.add_subplot(121, projection='3d') # 3D plot

sensor_labels = [f"Sensor {i + 1}" for i in range(len(sensors))]
time_steps = []
distance_history = [[] for _ in range(len(sensors))]
time_counter = 0

# Initial charge position and velocity
charge_pos = np.array([0.5, 0.5, 0.5])
velocity = np.array([0.02, 0.03, 0.01])
dt = 0.1 # Time step

while True:
# Update charge position (simulate bouncing off walls)
charge_pos += velocity * dt
for i in range(3):
if charge_pos <= 0 or charge_pos >= 1:
velocity = -velocity # Reverse direction on collision
charge_pos = max(0, min(1, charge_pos)) # Keep within bounds

# Generate synthetic electric field data
sensor_readings = np.array([compute_electric_field(sensor, charge_pos) for sensor in sensors])

# Solve for charge position using least squares optimization
initial_guess = np.array([0.5, 0.5, 0.5])
result = least_squares(error_function, initial_guess, args=(sensor_readings,))
estimated_position = result.x

# Compute distances
distances = [np.linalg.norm(sensor - estimated_position) for sensor in sensors]
time_steps.append(time_counter)
time_counter += dt

for i in range(len(sensors)):
distance_history.append(distances)

# Clear and redraw 3D plot
ax.clear()
ax.scatter(sensors[:, 0], sensors[:, 1], sensors[:, 2], c='b', marker='o', label='Sensors')
ax.scatter(charge_pos[0], charge_pos[1], charge_pos[2], c='g', s=200, label='True Charge Position')

# Draw lines connecting sensors to the estimated charge position with varying color intensity based on distance
for sensor in sensors:
distance = np.linalg.norm(sensor - estimated_position)
ax.plot([sensor[0], estimated_position[0]],
[sensor[1], estimated_position[1]],
[sensor[2], estimated_position[2]],
'r.-.', lw=min(20, 2 / distance), alpha=min(0.5, 0.5 / distance))

ax.set_xlabel('X Position (m)', fontsize=24, fontname='Arial', labelpad=20)
ax.set_ylabel('Y Position (m)', fontsize=24, fontname='Arial', labelpad=20)
ax.set_zlabel('Z Position (m)', fontsize=24, fontname='Arial', labelpad=20)
ax.tick_params(axis='both', which='major', labelsize=24)

# Remove bounding box lines while keeping the grid
for axis in [ax.xaxis, ax.yaxis, ax.zaxis]:
axis._axinfo["grid"].update(linewidth=0.5) # Keep grid lines but make them subtle
axis._axinfo["grid"].update(color=(0.7, 0.7, 0.7, 0.7)) # Light grey grid

# Hide the extra bounding box lines
ax.xaxis._axinfo["grid"].update(linewidth=0)
ax.yaxis._axinfo["grid"].update(linewidth=0)
ax.zaxis._axinfo["grid"].update(linewidth=0)
ax.xaxis._axinfo['tick']['outward_factor'] = 0 # Remove extra tick lines
ax.yaxis._axinfo['tick']['outward_factor'] = 0
ax.zaxis._axinfo['tick']['outward_factor'] = 0
ax.grid(True)

# Clear and redraw distance vs. time plot
ax_dist.clear()
for i in range(len(sensors)):
ax_dist.plot(time_steps, distance_history, label=f'Sensor {i + 1}')

ax_dist.set_xlabel('Time (s)', fontsize=24, fontname='Arial', labelpad=15)
ax_dist.set_ylabel('Distance to Charge (m)', fontsize=24, fontname='Arial', labelpad=15)
ax_dist.tick_params(axis='both', which='major', labelsize=24)

plt.pause(0.01) # Pause to allow real-time update
plt.tight_layout()


# Run the real-time tracking simulation
track_bouncing_charge()


The output looks like:

The left image shows how the ball moves, and the right shows the distance of the ball to the corners.

My question is : How to remove the extra 2D coordinate axes around the 3D plot? This is a simulation of a ball moving inside a box.

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