Fixed typos.

example_1.md

@@ -5,27 +5,26 @@
 
 The goal of this example is to give you an enhanced understanding of how to control the mobile base by sending `Twist` messages to a Stretch robot.
 
-Begin by running `roscore` in a terminal. Then set the ros parameter to *navigation* mode  by running the following commands in a new terminal.
+Begin by running the following command in a new terminal.
 
 ```bash
-# Terminal 2
-rosparam set /stretch_driver/mode "navigation"
+# Terminal 1
 roslaunch stretch_core stretch_driver.launch
 ```
 
-To drive the robot forward with the move node, type the following in a new terminal.
+Switch the mode to *navigation* mode using a rosservice call. Then drive the robot forward with the move node.
 
 ```bash
-# Terminal 3
+# Terminal 2
+rosservice call /switch_to_navigation_mode
 cd catkin_ws/src/stretch_ros_tutorials/src/
-python3 move.py
+python move.py
 ```
 To stop the node from sending twist messages, type **Ctrl** + **c**.
 
 ### The Code
 Below is the code which will send *Twist* messages to drive the robot forward.
 
-
 ```python
 #!/usr/bin/env python
 

example_2.md

@@ -55,7 +55,7 @@ To filter the lidar scans for ranges that are directly in front of Stretch (widt
 ```bash
 # Terminal 3
 cd catkin_ws/src/stretch_ros_tutorials/src/
-python3 scan_filter.py
+python scan_filter.py
 ```
 
 Then run the following command to bring up a simple RViz configuration of the Stretch robot.

example_4.md

@@ -13,7 +13,7 @@ the `rviz` flag will open an RViz window  to visualize a variety of ROS topics.
 ```bash
 # Terminal 2
 cd catkin_ws/src/stretch_ros_tutorials/src/
-python3 marker.py
+python marker.py
 ```
 The gif below demonstrates how to add a new *Marker* display type, and change the topic name from `visualization_marker` to `balloon`. A red sphere Marker should appear above the Stretch robot.
 

src/multipoint_command.py

@@ -42,7 +42,7 @@ class MultiPointCommand(hm.HelloNode):
 		# IMPORTANT NOTE: The lift and wrist extension can only go up to 0.2 m/s!
 		point0.velocities = [0.2, 0.2, 2.5]
 
-		# Provide desired velocity of the lift (m/s^2), wrist extension (m/s^2),
+		# Provide desired accelerations of the lift (m/s^2), wrist extension (m/s^2),
 		# and wrist yaw (rad/s^2)
 		point0.accelerations = [1.0, 1.0, 3.5]