William Sandqvist [email protected] Our PIC ”Kitchen Lab” Who has said that PIC-processors aren’t Rocket Science ?
Our PIC ”Kitchen Lab”
Jan 03, 2016
Our PIC ”Kitchen Lab”. Who has said that PIC-processors aren’t Rocket Science ?. REXUS. R ocket-borne E xperiments for U niversity S tudents. ESRANGE Sweden mar 2010. Mission, deploy a web in space. Mission To deploy a net in zero gravity. What to do with a web in space?. - PowerPoint PPT Presentation
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
William Sandqvist [email protected]
Our PIC ”Kitchen Lab”
Who has said that PIC-processors aren’tRocket Science ?
William Sandqvist [email protected]
REXUSRocket-borne Experiments for University Students
ESRANGE Sweden mar 2010
William Sandqvist [email protected]
Mission, deploy a web in space
MissionTo deploy a net in zero
gravity
William Sandqvist [email protected]
What to do with a web in space?• Could be used as an Antenna?
• Could be a lightweight platform for miniature crawling construction robots?
William Sandqvist [email protected]
How to unfold a web in zero gravity?
?( when Fuglesang isn’t there to help )
William Sandqvist [email protected]
First: How to fold a web?
From Mattias Gärdsback and Gunnar Tibert
This is the Miura-Ori folding scheme
Some Japanese origami is needed
William Sandqvist [email protected]
Scater spinning on ice
Initial Unfold
Law of the Conservation of Angular Momentum
Rotation will slow down!
William Sandqvist [email protected]
The ”spinning scater principle”
The ”spinning scater priciple” can’t unfold the net.
If the initial rotational speed is to low, the final centrifugal forces won’t be strong enough to deploy the net.
If the initial rotational speed is to high, the energy transfered from the hub to the net will cause oscillations – then the net will be tangled.
Won’t Work!
Rotate the hub with weights attached to the corners of the web, then the centrifugal force will unfold the web?
William Sandqvist [email protected]
Reaction wheel to ”help” the rotationThe stabilizing rotation of the web
centrifugal force
Reaction wheel
hub
William Sandqvist [email protected]
Simulation of the reaction wheel motor voltage during controled unfolding
Simplified control is possible!
From Mattias Gärdsback and Gunnar Tibert
William Sandqvist [email protected]
Gyro to sense hub rotation
The gyro
Sensitivity: 5mV/ °/s
1 Hz (360°/s) 1.8 V0.1 Hz 0.2V0.01 Hz 0.02V
William Sandqvist [email protected]
Reaction wheel controler card
RWmotor
Now ejected signal
Gyro (x),( y), z,temperature
Release the net signal
E [V]Start now signal
PIC Micro PWM
DIR
With simplified control, one simple PIC Micro could do the job!
William Sandqvist [email protected]
Zero gravity on earth?
Problem: motor cold not move flywheel!The gravity caused friction in the bearings.
When the flywheel was lifted with a string everything worked! Zero gravity on earth!
William Sandqvist [email protected]
Wait for:Esrange Februari/March 2010
Sorry: We didn’t deliver a working board in time.
(and there were other problems elsewhere)
William Sandqvist [email protected]
Circuitboard with testprogram
William Sandqvist [email protected]
Circuitboard and testprogram.
a auto testm motor testg gyro testl led tests signal testwrite command:
A degree project was performed by student Andreas Svensson in order to assure that we in the future, given a second chance, have a board that works,
Demonstration with PICKit2 UART Tool
William Sandqvist [email protected]
a auto testm motor testg gyro testl led tests signal testwrite command:
Related Documents
