2013:Shooter Storage Subteam

Shooter/Storage Design

In the storage mechanism, discs enter through the feeder slot. A banner sensor detects that the disc has entered. Fan blades rotate one quarter turn. A flag sensor detects when the fan blades are in the right position to receive the next disc. This continues until all discs are loaded. A second flag sensor detects when the blades are in the correct position so the disc will drop down into the shooter mechanism. The blades then rotate each time to push the discs into the shooter mechanism.

In the shooting mechanism, another banner sensor detects when each disc is in the ready state for shooting. A single servo moves a piece of metal that sticks up though a slot in the base plate to make sure that the disc does not move into the shooting wheel until the wanted time. When time for shooting comes, the servo moves the piece of metal back down into the slot while another servo pushes the disc into the shooting wheel. An encoder will be on the shooting wheel to control the speed of the wheel.

The lifting mechanism uses a lead screw. The lead screw is in the center and on each side there are two linkages that extend or detract when the lead screw moves forward or backwards. This is what creates the different angles for the shooting mechanism. A potentiometer will be used for measuring the angle. Lifting mechanism will allow the shooter to go from vertical (storage) and approximately 20 degrees (lowest possible shooting angle). This design will permit a variable shooting angle.

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NOTE: the following is based on the outcome of the programming team going through the sub-system and review they had will electrical and the operator controls sub-teams on 1/26. This needs to be reviewed to make sure these notes concur with what everyone took away. This will also need to be reviewed by strategy.
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Sensors:

Area	Type	Description	Operation	Notes
Storage	Banner	Detects when the disc is in the feeder slot (slot #1)	When in feed mode, if not the 4th disc, the blades will automatically index the disc to the next slot (slot #2)
Storage	Feed Flag/Slotted Optical	Detects when fan blades are in position to recieve disc from the human player	Blades will move quickly until the flag trips the sensor, then the blades will be moved slowly until the flag is no longer tripping the sensor. This will allow the discs to index quickly and more accurately.	Place sensor so the blade in the proper position just after the flag leaves the sensor
Storage	Flag/Slotted Optical	Detects when fan blades are in position so the disc will drop into the shooter mechanism	Blades will move quickly until the flag trips the sensor, then the blades will be moved slowly until the flag is no longer tripping the sensor. This will allow the discs to index quickly and more accurately.	Place sensor such that the blade in the proper position just after the flag leaves the sensor
Shooter	Banner	Detects when the disc is in the shooting mechanism	If not in shooter broken mode, disc will only shoot when this sensor is tripped and motor is up to speed
Shooter	Encoder (US digital 100 cpr)	Detects shooter wheel rpm	If not in shooter broken mode, disc will only shoot when the wheel matches the desired speed and disc is detected by the banner the sensor
Lift	Potentiometers (2)	Measures the angle of the scissor lift mechanism	If not in lift broken mode, this will be used to match the angle with the slider on the controls	Second potentiometer is a redundant sensor (back-up) [programming does not plan to switch pots in software]
	Camera	Used to see targets for shooting and the pyramid for climbing. Maybe for aligning during autonomous.	Faces the shooter side for normal/non-climbing driving. When climbing, the camera will flip 180 and the displayed image will be rotated. The direction is control by the operator controls (see Drivetrain Design)	Center align with the the exit for the shooter. Fixed so that it does not move when shooter/storage mech angle changes. Needs to tilt/flip vertically 180 degrees so it can face the climber side of the robot. Height needs to such that the driver has clear view of the targets, and when flipped the driver needs to be able to see the pyramid.

Motors/Servors/Actuators:

Area	Type	Description	Operation	Notes
Storage	Snow Blower Motor	Moves the fan blades	If not in storage broken mode, the flags are used to detect the position of the blades. The motor is moved 'fast' until the flag is tripped, and then the motor moves 'slow' until the flag is no longer tripping the sensor. If in storage broken mode, a button on operator controls (more likely a joystick button) is used to move the motor; the motor will move at a constant speed for as long as the button is pressed.
Shooter	Mini-CIM	Moves the shooter wheel	If not in shooter broken mode, the encoder is used by a PID loop to control the speed of the wheel. If in shooter broken mode, the slider on the operator controls will set the speed of the motor.
Shooter	Blocker Servo	Moves a stopper up from a slot in the base plate to stop the movement of the disc from touching the wheel.	If not in completely broken mode, servo is moved when there is a request to fire and there is a disc in the shooter mech and the wheel is at the desired speed
Shooter	Pusher Servo	Moves a flipper that slams the disc into the shooter wheel	If not in completely broken mode, servo is moved after the blocker servo has moved the stopper out of the way
Lift	TBD motor	Moves a lead screw to raise and lower the entire shooter/storage mech	If not in lift broken mode, the pot is used to control the speed of the lead screw and determine the angle of the entire mech. The angle is determined by a slider on the operator controls. In lift broken mode, the slider will just move the motor forward/backwards while the slider is on up/down from the center position.

Lights (on robot):

Area	Type	Description	Operation	Notes
		OK to feed	Will be 'green' when it is ok for the human player to feed a disc. Will be 'red' when the it is NOT ok to feed a disc. It is OK to feed when the entire mech is at the proper angle AND there are less than 4 discs in the robot AND the fan blades are in the feed position.	Locate the light so it can be seen by the human player (e.g. near the feed slot on the storage mech)
		Number of discs in the robot	4 individual lights (similar in concept to the 3 we had last year). The count will increase when the Feed Banner sesnor goes from untripped to tripped. The count will decrease when a disc is shoot. Light will have no meaning when broken switch is flipped.	Since there are no sensors for each disc slot, the SmartDashboard will need a way for the drivers to indicate how many discs where put in the robot at the start of the match. The thought is that these lights will have a different meaning when climbing.
		The shooter is at the desired angle	Used to aid the aux driver because the lift may move 'slow' compared what the aux driver is expecting. Could use the Number of discs lights: 'green' is at desired angle w/at least one disc in robot, 'red' is not as desired angle w/at least one disc in robot; 'flashing white' when not at desired angle wno discs in robot.
		Unable to deploy	Used to aid the aux driver because the shooter is not at the proper angle to allow deployment when the Deploy Button is pressed. Flash all other lights like a rave.

Operator Controls:

Area	Type	Description	Operation	Notes
SmartDashboard		Discs in Robot	Set by driver prior to match to indicate how many discs they put in the robot for the match
Aux Driver	Button	Feed Mode	When pressed, the lift will put the entire mech at the angle needed for feeding and storage will automatically advance discs as they are feed into the robot.	The aux driver must continue to press the button to stay in feed mode.
Aux Driver	Button	Tilt camera up	While pressed, the camera will tilt up.	Relative to orientation of camera ("front" of robot).
Aux Driver	Button	Tilt camera down	While pressed, the camera will tilt down.	Relative to orientation of camera ("front" of robot).
	Broken Switch	Storage Broken	When not broken, the discs will automatically be indexed to the next slot until there are four discs. When broken, the aux driver will use a joystick button to move the fan blade motor (motor moves at constant speed and for the duration the button is preseed).	Set broken if Feed Banner is not working OR if the Feed Fan Flag is not working OR if the second/drop Fan Flag is not working
	Broken Switch	Shooter Broken	When not broken, the discs will automatically fire when: fire button is pressed, a disc is in the shooter mech, and the wheel is at speed. When broken: the shooter motor runs at one speed, which is control by the slider; the blocker & pusher servos will move when the fire button is pressed.	Set broken if the Shooter Banner is not working OR the Shooter Encoder is not working.
	Broken Switch	Lift Broken	When not broken, the lift moves automatically to the angle determined by the position of the slider. When broken the lift motor moves the mech up while the slider is above the its center position; the lift motor moves the mech down while the slider is below its center position; the lift motor does not move while the slider is in its cetner position; there will be a 'dead' spot around center; motor will move at one speed.	Set broken if the pot is not working.
	Broken Switch	Shooter/Storage Completely Broken	When not broken, enter mech works based on the above 3 broken switches. When broken, nothing will work.	Set broken if any motors/servors/actuators are not working.

Motor Choice: Selected motor for the storage machine is the am-2235 - Snow Blower Motor - Has adequate rpm, is low profile and has more than enough torque. Motor Characteristics- Frisbee is 1/3 pound = 5oz. 4 frisbees so 4 * 5oz. = 20 oz. Required torque =20oz. * 5.5 in.(point of contact to each frisbee) = 110 oz./in. Indexer speed estimate= 1/4 sec per 1/4 revolution = 60rpm Rule of thumb for rpm is 2 * 60rpm = 120 rpm.

Selected motor for shooter is the Mini-CIM  becuase higher rpm, smaller size and lower complexity than the M7-RS775-18 BaneBots motor. 

Part Number	Motor Name	Weight (lbs)	Max Power (W)	Stall Torque (oz-in.)	Free Speed (rpm)	Free Current (A)	Stall Current (A)
am-2235 S	Snow Blower Motor	1.11	30	1600	100	5	24
217-3371	Mini-CIM	2.16	229	198	6200	1.8	56

Resources

Wheel options:
- plain razor scooter:
- Razor electric scooter (espark) rear wheel with sproket:
- Razor electic scooter (e100) rear wheel with sproket:
Looks like e100 is 4.92" ->

Solenoid "Kicker"; 1 in stroke part number 69905K851

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6 inch pneumatic wheel

Access Casters Catalogs

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Shooter Storage's Engineering Notebook

Week 2

== Week 3 == ***** == Week 4 == *Completed AutoDesk construction of Lead screw manipulation device: *[[Lead_Screw:Lead_Screw.PNG]]   *Created Drawings of parts needing machining [[File:Lead_Screw_Block.PNG]] [[File:Mount_Slab.PNG]]

Week 6

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Please Label All Notebook Pages 2013:Shooter Storage XX.XX to avoid confusion.