variable vector countermeasure suit (v2suit) for space...
TRANSCRIPT
THE V2SUIT IS A COUNTERMEASURE PLATFORM THAT USES GYROSCOPIC MOTION TO PROVIDE A “VISCOUS RESISTANCE” DURING MOVEMENTS TO MITIGATE SPACEFLIGHT PHYSIOLOGICAL ADAPTATION
NASA Human Research Program Investigators’ Workshop
January 13–15, 2014 Galveston, TX
THE V2SUIT IS AN ENABLER FOR SPACE EXPLORATION MISSION TECHNOLOGIES, INCLUDING HUMAN ADAPTATION AND COUNTERMEASURES, HEALTH MONITORING, ROBOTIC INTERFACES, AND ADAPTATION AND OPERATIONS DURING ARTIFICIAL GRAVITY.
Wearable control moment gyroscopes arranged in a pyramid array will act in a coordinated manner to provide a resistance when movements are parallel to “down”.
Upper Arm Module
Power &
Processing
Lower Arm
Module
Lifesize Mannequin
An integrated countermeasure system has a measurable impact : Reduce number hours per day allocated to exercise Reduce exercise equipment mass and volume Enable optimal performance during mission-specific gravitational transitions
K. R. Duda1, R. Vasquez1,2, A. J. Middleton1, M. L. Hansberry1, D. J. Newman2, S.E. Jacobs3, and J. J. West1
1The Charles Stark Draper Laboratory, Inc., 2Massachusetts Institute of Technology, 3David Clark Company, Inc. [email protected] | (617) 258-4385
Variable Vector Countermeasure Suit (V2Suit)
for Space Habitation and Exploration
The V2Suit “Down” tracking algorithm enables the wearer to initialize the direction of inertial “down” and uses data from onboard IMUs to track the movement and orientation of the individual modules with respect to that direction of “down.”
Flywheel Inertia: 5e-5 kgm2 Constant Gimbal/Spin rates: 60rpm/15000 rpm
0 0.2 0.4 0.6 0.8 10
0.02
0.04
0.06
0.08
0.1Torque
Time (s)
Torq
ue (
Nm
)
X
Y
Z
0 0.2 0.4 0.6 0.8 1-40
-20
0
20
40Gimbal Rate
Time (s)
Gim
bal R
ate
(rp
m)
1
2
3
4
0 0.2 0.4 0.6 0.8 1-1.5
-1
-0.5
0
0.5
1
1.5Gimbal Angle
Time (s)
Gim
bal A
ngle
(ra
d)
1
2
3
4
0 0.2 0.4 0.6 0.8 10
0.02
0.04
0.06
0.08
0.1
Time (s)
Magnitude D
iffe
rence (
Nm
)
Magnitude Difference Between Command Torque and Applied Torque
Difference
Mean
Flywheel Material: Tungsten Flywheel Inertia: 4.4450e-05 kgm2
Spin Rate: 15,000 RPM Command Torque Magnitude: 0.1 Nm
The steering laws for the array incorporate data from the onboard IMU and the “down” tracking algorithm to send gimbal rate commands which point the gyroscopic torque vector in the desired direction.
-0.5
0
0.5
1
0
0.5
1
-1
-0.8
-0.6
-0.4
-0.2
0
XY
Z
Trajectory
Down
Module X Axis
Module Y Axis
Module Z Axis
-0.5
0
0.5
1
-0.5
0
0.5
1
-1
-0.5
0
0.5
XY
Z
Trajectory
Down
Module X Axis
Module Y Axis
Module Z Axis
-0.5
0
0.5
-1
-0.5
0
0
0.2
0.4
0.6
0.8
1
Mo
du
le X
ZI
XI YI
ZM
XM
YM
D
ZI
XI YI
END ZM XM
YM
D
ZI
XI YI
ZM
XM
YM
START
D
-0.5
0
0.5
0
0.5
1
0
0.2
0.4
0.6
0.8
1
Mo
du
le X
Real Arm Lift
Simulated Arm Lift
Down Tracking Module Axes Tracking
Selected IMU evaluated during operating time of 1 hour with less than a 1 degree offset from true “down.”
Measured offset from “down” over time
The prototype demonstrates the V2Suit concept – closed loop control from “down” tracking to CMG actuation. Initial design of a 4-CMG array was conducted and fabricated using commercial off-the-shelf components, and custom machining when necessary. The system is controlled from a desktop computer. Evaluations demonstrated the ability to initialize and track against a specified direction of “down,” simultaneously command 4 CMGs, and that single module power consumption was 8-10 Watts during operation.