1. Secondary Controller MOOS Interface
Mark Morris, Sr. Software Engineer
iRobot Maritime Systems
Small Business Innovation Research (SBIR) Program Data Rights
Contract # N C-0020, N C-4108, N M-0209, and N C-0277
Contractor Name: iRobot Corporation
Address: 4625 Industry Lane, Durham NC 27713
Expiration of SBIR Data Rights Period: November 30, 2015
The Government’s rights to use, modify, reproduce, release, perform, display, or disclose technical data or computer software marked with this legend are restricted during the period show as provided in paragraph (b) (4) of the Rights in Noncommercial Technical Data and Computer Software – Small Business Innovation Research (SBIR) Program clause contained in the above identified contract. No restrictions apply after the expiration date shown above. Any reproduction of technical data, computer software, or portions thereof marked with this legend must also reproduce the markings.

2. iRobot Maritime Vehicles Running MOOS
Hybrid surface/UUV vehicle
High speed transit
Streaming sensor data to user console
Hybrid surface craft/detachable UUV
Vectored thruster
Autonomous or joystick
Transphibian
6 degrees of freedom
Oscillating Foil Thrusters (“Nektors”)
Embedded payload processing or real-time link to user
Low-cost modular UUV
Minimal hardware and mechanical costs
24” of flooded payload space
Sensor payload on nose
Ethernet and power to modules
Man-portable AUV
Small (<5” diameter)
4 independent fins plus main motor
Dry hull and nose payload modules

3. Secondary Controller Description
The iRobot Secondary Controller is code that exists within iRobot’s proprietary Helm MOOS module that responds to messages specified in the iRobot Secondary Controller MOOS Interface document.
The purpose of the Secondary Controller is to enable anyone with an iRobot UUV running MOOS to drive that vehicle.
This can be done by issuing SC_OBJ (Secondary Controller Objective) commands to the MOOS database.

4. Partners Using iRobot’s Secondary Controller Interface
MIT
Demonstrated Feature-Based Navigation with iRobot Legacy Ranger and Transphibian vehicles
Seebyte
Demonstrated Sensor-Based Servoing with iRobot Transphibian
Stevens Institute of Technology
Currently operating in the Hudson river with iRobot Ranger and Transphibian vehicles

5. Secondary Controller Message Flow Chart
Helm
Payload
1 Hz
SC_OBJ_<objective_type>
SC_ERROR
SC_OBJ_COMPLETE
SC_ABORT
Controller
Controller Commands

6. Attitude Objective Message Format Example
Example SC_OBJ_ATTITUDE Message:
MOOS Message Name: “SC_OBJ_ATTITUDE”
MOOS Message Value: “REFERENCE=attitude1,
VEHICLE_MODE=TRANSIT,
HEADING_MODE=ABS,
HEADING_VALUE=110.1,
ROLL_MODE=ABS,
ROLL_VALUE=2.2,
PITCH_MODE=ABS,
PITCH_VALUE=3.3,
Z_MODE=CONSTANT_DEPTH,
Z_VALUE=3.6,
Z_UNIT=METERS,
SPEED_UNIT=RPM,
U=2.6,
V=0.0,
W=0.0,
DURATION=10.0”

7. Attitude Objective Message Fields
• REFERENCE: A name to define this objective
• VEHICLE_MODE: Defines the controller mode setting. This is directly passed through to the controller and therefore can be any string that has been defined for the vehicle under consideration. For example, Transphibian can operate in either a TRANSIT or a STATION_KEEPING mode. The STATION_KEEPING mode is used for maintaining depth and heading, with 0 pitch and 0 roll, while thrusting in the u (surge) and v (sway) vectors. In the future this mode will also support variable pitch and roll control.
• HEADING_MODE: A descriptor for the HEADING_VALUE to instruct the controller whether to control the heading if set to ABS, yaw rate if set to RATE, and leave uncontrolled if set to OFF.
• HEADING_VALUE: The value in degrees [0(north) – 360] to be passed to the heading controller for a HEADING_MODE of ABS, and in degrees/sec for a HEADING_MODE of RATE.
• ROLL_MODE: A descriptor for the ROLL_VALUE to instruct the controller whether to control the roll if set to ABS, roll rate if set to RATE, and leave uncontrolled if set to OFF.

8. Attitude Objective Message Fields
• ROLL_VALUE: The value in degrees [-180 – 180] to be passed to the roll controller.
• PITCH_MODE: A descriptor for the PITCH_VALUE to instruct the controller whether to control the pitch if set to ABS, pitch rate if set to RATE, or leave uncontrolled if set to OFF.
• PITCH_VALUE: The value in degrees [-90– 90] to be passed to the pitch controller.
• Z_MODE: The behavior used to achieve the position in the Z axis. CONSTANT_DEPTH will maintain the vehicle at a constant depth given as the Z_VALUE parameter. CONSTANT_ALTITUDE will maintain the vehicle at a constant altitude given as the Z_VALUE parameter. IDLE will disable the behavior.
• Z_VALUE: The value to be passed to the Z controller.
• Z_UNIT: METERS or FEET
• SPEED_UNIT: Specifies the units of U,V, and W in MPS, KNOTS, FPS, or RPM
• U: The desired forward speed (water referenced) of the vehicle.
• V: The desired lateral speed (water referenced) of the vehicle taken positive to starboard.
• W: The desired vertical speed (water referenced) of the vehicle taken positive down.
• DURATION: The time in seconds to execute the objective before timing out. A setting of 0 is treated as infinite.