perm filename UNI1.V[1,VDS]1 blob sn#269993 filedate 1977-03-15 generic text, type C, neo UTF8
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C00003 00002	\|\\M1BDR30\M2SIGN57\M3NGR25\M4NGR20
C00007 00004	\|\\M1BDR30\M2SIGN57\M3NGR25\M4NGR20\F1\CSPECIFICATIONS SUMMARY (cont.)
C00010 00005	\|\\M1BDR30\M2SIGN57\M3NGR25\M4NGR20\F2\CUNIMATION
C00021 00006	\|\\M1BDR30\M2SIGN57\M3NGR25\M4NGR20\F1\CCONTROL SYSTEM
C00044 ENDMK



\CIn response to General Motors Specifications for their
\CPUMA SYSTEM-Manipulator and Controls
\CDated January 17,1977

\CRFQ #7056-18



Shoulder Height-				610  mm
Upper Arm link length-			400  mm
Forearm link length-			400  mm
Wrist envelope diameter-			80   mm

Manipulator weight-			40kg max.

Arm swing range-				270 deg. min.
Shoulder rotation-				180 deg. min.
Elbow rotation-				240 deg. min.
Wrist bend-					220 deg. min.
Wrist rotate-				360 deg. min.
Wrist roll (optional axis)-			360 deg. min.

Arm swing-					135 deg/sec
Arm shoulder and elbow rotate
sufficient to meet vertical and
horizontal slew rate specs. of 		500 and 1000 mm/sec

Wrist bend-					360 deg/sec
Wrist rotate-				360 deg/sec
Wrist roll (opt.)-				360 deg/sec

All motions designed for critical or overdamped motion.
1G maximum part center acceleration with maximum load.

Repeatability of playback of "place to teach" motions- within .1mm, assumming
repeating motion with same load and conditions.

Max load capacity-			3.5 kg. including gripper and fittings.
Max force capacity-		6  kg. min. in any direction.
Drive system-			D.C. Electric Motors.Totally internal, easily accessable.
Power Consumption-		500 watts peak. (from controller power supply).
Feedback devices-			Optical Incremental Encoders on each motor shaft.
					Tachometers as required.

Mounting-				Base mounted with 4 bolts and alignment pins.
Mounting Fixture-			Allows conveyor side mounting, also holds electronics.



Power amplifiers-			D.C. type linear and switching amplifiers.
Error summing-			Digital, for no drift or offset errors.
Motion limit stops-			Mechanical, Electrical and Software limits on all joints
Power sequencing-			Solid State
Control sequencing-		FET switches and software control.
Weight-				40kg. max including power supply, and computer.
Size-					18"W x 18"D x15"H.  Enclosed, fan cooled box
					on slides with handles.
Connections-			All quick connect type plugs to GM specs.
Power Reqd.-			115/230VAC- 700 watts max.

Computer-				DEC, LSI-11 computer
Memory-				PROM, mos RAM
Capacity-				Minimum of 256 program steps total, expandable.
External Controls-			Interfaces to TTL or 110 VAC inputs or outputs
					minimum of 8 each.
Storage-				Cassette or PROM permanent backup program storage.
Repeating-				Software implemented conditional branching.
Collision Protection-		Software, and electronic trajectory deviation
					sensing and shutdown.  External switch outputs.
Power Failure-			Failsafe type brakes on shoulder and elbow joints
					to support arm in case of power failure.
					Memory battery backup power supply for 1 hr. 
					power outages.


Software type-			High level, similar to VAL language.
Input/Output-			Assignable function button box. With
					optional 3 axis joystick.

Important Software Features-	Point to point mode or continuous path mode
					Speed control on a motion by motion basis.
					Provision of correcting or updating positions.
					Allows addition, deletions,and changes of steps or
					groups of steps.
					Incremental teach mode, in various coordinate
					Many more extras as a subset of VAL language.


\CMechanical System Design
	Unimation, Inc.   proposes  to  develop an  all  electric  5  axis
(optionally 6-axis) anthropomorphic configuration manipulator to meet  the
General Motors Corp. PUMA
system requirements.  We have chosen an equal link length, all parallel or
normal axis configuration as  this results in  the maximum working  volume
with minimum manipulator mass and work space intrusion.

	The dimensions  of  the  links  have  been  chosen  to  allow  the
manipulator to reach all points in the primary work area and nearly all of
the overall  working  volume  specified  in  the  Functional  Requirements
Section of the  RFQ.  As  an added  feature of  this configuration,  large
additional working volumes are also available outside the defined regions.
Furthermore, multiple solutions (different arm geometries resulting in the
same terminal point),  allow the  arm to  reach most  points in  different
configurations, a definite advantage when obstacles must be avoided  while
moving or while picking or placing.

	Direct current, permanent magnet electric  motors will be used  on
all axes.  These drive units will be integrated power-feedback units,  all
having motor, position encoder, tachometer, and brake (joints 1,2,3  only)
in one unit, on a single common shaft. The drive units will be placed  for
easy accessability and will  generally be coupled  by tubular, high  speed
extension shafts to suitable gearing located at each joint.

	By placing all  motors away  from each  joint, AND  away from  any
critical  length  determining  structure,  effects  of  motor  heating  on
structural dimensions will be minimized.  In addition, partial mass balancing will
significantly reduce steady state power requirements.

	The drive  units for  joints 1,2,3  (shoulder and  elbow) will  be
nearly identical.  Access to these units will be from the back of the  arm
structure, by merely  removing protective covers.   This will allow  quick
and easy removal of  an entire drive unit.   These three axis drives  will
also be fitted with  common shaft mounted failsafe  brakes to support  the
manipulator in the event of power failure, and when shut down.

	The wrist  degrees  of freedom  will  consist of  a  2 or  3  axis
differential unit, driven by electric drive units mounted near the  elbow.
These electric drive units will each consist of a high performance  torque
motor, coupled by a torque  tube type shaft to  the wrist gearing.  The  2
and 3 axis wrists will  not be the same,  but will be interchangeable  and
have the  same  link  lengths  and external  dimensions.   As  an  aid  to
efficient computer control  of this manipulator,  the wrist geometry  will
feature intersecting and perpendicular axes.

	The manipulator structure will be characterized by large  section,
thin wall, tubular, formed and seamed high strength sheet aluminum shells,
anodized for  scratch and  corrosion resistance.   Gearboxes, and  bearing
housings will be manufactured from  n.c. machined aluminum plate and  bar,
and Almag castings.   All power  train gearing  will be  of heat  treated,
alloy steel gears operating in sealed and shielded grease packed housings.
Large diameter (e.g.- an 11 inch  diameter swing motion drive gear),  high
ratio gearing will maximize drive stiffness and minimize backlash and gear
wear adjustments.

	The  tubular  monocoque  type  manipulator  structure  will  fully
contain all  wires, drives,  plumbing, etc.   Large section  bearings  and
tubular shafts at each  joint will act  as interjoint conduits.   Optional
forced air cooling will intake air  at the "head" and pressurize the  arm.
Exhaust will be out past and through the drive motors and out through  the
drive unit protective, inspection and maintainance covers.

	A separate air  line and  integral solenoind  valve assembly  will
provide a  switched pressure  or  vacuum source  out  near the  wrist  for
control  or  operation  of  a  terminal  effector  or  other  accessories.
Internal valve  placement,  even  on  a  manipulator  as  small  as  this,
minimizes delay and improves controllability of pneumatic grippers, etc.

	The motors, drives and structure will all be selected and designed
to produces a manipulator with 3.5kg  load capacity and typically 1g  part
center acceleration.   Emphasis will  be placed  on a  rigid,  lightweight
design.  Unimation Inc.  already has experience  with manipulators  having
accelerations in excess of 4g's, and natural frequencies of over 50hz.

	Four through
the base bolts will hold the  entire manipulator securely in place on  its
mounting structure.  Base mounted precision  placed dowel pins will  allow
repeated accurate replacement of the manipulator. The mounting structure
will also be the manipulator to conveyor attaching structure.
By applying construction and design approaches outlined above, the
entire manipulator weight, less controller, will be under 40kg.

	To  meet  repeatability  requirements, incremental  rotary  optical
encoders have been  selected.  These non-contacting,  glass disk  devices,
with bi-directional counting tracks AND zero references will be mounted on
the drive motor shafts.  On a small arm, high performance is contingent on
high motor torque to  weight and torque to  inertia ratios.  Small,  shaft
mounted encoder  disks  have lower  moments  of inertia  than  most  small
resolvers or other high resolution  position transducers.  For cost,  life
and stability reasons, the incremental encoder represents a best choice at
the present  time.  Laser  based interferometric  measurements may  become
realistic in the future, but not within the time frame of this project.

	Calibration on power turn on  will be accomplished in software  by
slowly driving all joints to  electrical reference stops and  initializing
the encoder  pulse  counters.  In  the  event of  arm  motion  constraints
preventing  this  initialization  procedure,  an  optional  analog  coarse
position reference unit can  be made available.   This will enable  almost
immediate initialization with only small  arm search motion required.   In
motion error checking will occur on a continuous basis using the once  per
turn zero reference track and the count electronics carry logic.

	To prevent accidental runaway arm motion, three types of joint travel
limit stops will be employed.  Mechanical, electrical, and software stops will
constrain arm motion to user selectable ranges.  This is an essential safety feature
when operating side by side with humans.\.

\J	We have selected the Digital Equipment Corporation LSI-11 computer
to control the manipulator.  This computer has been designed by DEC to  be
used in industrial control applications where both data handling  programs
and  arithmetic  computation  routines must  be  performed.   General
Motors Corporation  currently utilizes  numerous PDP-11  series  computers
which have similar hardware and are software compatible with this machine.

	The manipulator  and hardware  controller  are interfaced  to  the
LSI-11 using standard  interface cards.  These  cards will also  interface
with almost any number of optically  isolated 110VAC and/or TTL inputs  or
outputs, to be monitored or controlled by the computer, on an interrupt or
continuous sample basis.

	The control software, as currently implemented by Unimation  -West
Coast Group (formely Vicarm, Inc.) is sophisticated.  We propose to use  a
modified form of this software, implemented in PROM(Programmable Read Only
Memory) as the control  program for this  system.  Actual motion  programs
will normally be implemented in mos RAM (Random Access Memory) which  will
be supplied for recording and current storage of manipualtor programs.  An
optional PROM board with software  controlled on board writing  capability
will be available for more permanent storage of more fully debugged,  long
term useage type  programs.  Program backup  will also be  provided by  an
optional tape  (Phillips type)  cassette unit,  and standby  1  hr. minimum
battery supply (memory only) in case of short term power outages.

	Each manipulator  axis will  have one  interchangeable servo  card
associated with it.  This card will contain all the logic and  electronics
to close the position (encoder), velocity (tachometer), and current( power
amplifiers  are  current  mode  rather  than  voltage  mode  for   greater
versatility and safety  when using permanent  magnet torque motors)  loops
under computer control. These servo  cards will primarily utilize  digital
logic elements with a miminum of  analog components to minimize long  term
drift and compensation adjustments.

	All manipulator motions will be trajectory controlled.  This means
that computer control of the manipulator is continuous and bi-directional.
Excessive motor currents, large deviation  from planned path, or  abnormal
operating conditions will result in an  immediate halt, as in the case  of
hitting an  obstacle,  jamming,  gripper malfunction,  excessive  time  to
complete motion, etc.

	The  control  computer,   power  supply,  motor   controller, power
amplifiers, brake drivers,  encoder boards,  etc.  will be  housed in  one
unit, approximately 18"W x18"D  x 15"H intended to  be mounted just  below
the manipulator in the manipulator attaching structure.  Connectors for AC
power, external  signals,  the manipulator  cable,  the  teach/programming
unit, and cassette tapeloading unit will be on the front panel along  with
several status indicators and an emergency shut down button.

	A  rack
mounted, sealed box  with handles  and drawer  slide supports  would be  a
typical mounting configuration, allowing quick removal and replacement of
the entire unit. The external support frame for this box will also be the
manipulator to conveyor attaching structure.

Estimated maximum  weight  of  this  unit will  be  40kg.

	The  controller  is  universal,  as  are  the  manipulators.   Thus
manipulators and controllers could  be switched or replaced  independently
with no  problems of  interchangeability.  Any  small differences  between
manipulators,  such  as   tolerances  in  link   lengths,  offsets,   mass
differences, etc. would be corrected  in a software calibration table  and
list of characteristics particular to each manipulator, like a curriculum-
vitae.  In the event of a  manipulator change, these constants would  also
have  to  be  changed  in  the  programs.   Re-programming  would  NOT  be
necessary, but  occaisional  point touch  up-  may be  required  if  these
constants are not sufficiently accurate.  It is presently unreasonable  to
suggest that all manipulators  will be absolutely interchangeable  without
calibration  changes,  as   this  would   require  extreme   manufacturing
tolerances and a costly level of assembly accuracy.  It is also  difficult
to see, that even if  this were possible, that  such a condition could  be
maintained throughout the life of such a manipulator.\.

\J	The VAL  language as  currently offered  by Unimation  as part  of
their complete system already contains  many of the essential features  of
the RFQ.  For this  new system the existing  software will be upgraded  to
employ a button box, with optional 3-axis joystick teach unit as the basic
low cost  arm-computer-human  interface.

	As  the  primary mode  for  most
precision motion and  placement tasks, instruction  will be done  entirely
from the teach box.  The arm will  be moveable in either joint axes  (arm)
coordinates, world  (cartesian)  coordinates,  or hand  (like  flying  and
airplane)  coordinates.   An  increment  button  would  allow  small  (one
resolution element)  increments, or  larger ones  (typically 10  elements)
each time the button is pushed.  Normal velocity based position mode would
also be  available.   Although  the  VAL  language  currently  utilizes  a
teletype or video display unit input/output  device for writing  high level,  English
language instruction motion programs, the "assembly line" version of  this
language would  more likely  use a  simplified set  of these  instructions
implemented on a limited number of software redefinable instruction keys.

	In the  second mode  of programming,  the unpowered  and limp  arm
would be physically moved  by hand from point  to point.  A record  button
would record precision points on command  or at timed or discrete  spacial
intervals in automatic (continuous path) mode.  This method of programming
is  possible  because  of  the  extremely  light  weight  and  high  drive
efficiency of the manipulator.

	Because the proposed VAL type software is so powerful, the ability
to quickly change teaching coordinate frames is practical and represents a
natural extension of  existing computer  capabilities rather  than a  hard
earned special feature.

	The VAL software  currently employs a  trajectory generator  which
computes trajectories for all  manipulator motions. This current  software
generates  controlled,   smooth  polynomial   interpolated  joint   motion
trajectories (continuous  path control)  between  end points.   Speed  and
position  of  all  joints   is  continuously  and  accurately   controlled
throughout each entire motion.   Straight line vector motions in  any
direction, and hand  coordinate  approaches  and  departs  are  other  already
built-in features  of this  software.   All these  instructions  currently
feature speed control allowing speeding up or slowing down of all  motions
on a motion by motion basis.

	Program update, touch-up, step addition, or deletion can all be provided off
line or on line, as all programs and program parts are stored in computer memory as linked
instruction lists. This allows easy program editing, as required.

	Because so many of the existing VAL language instructions meet the
software requirements of this system, a copy of the current VAL language 
is included with this proposal.  In addition, an EXISTING pertainant feature
summary is also included.  In fact, the only feature NOT shown in the
current instruction set- Conditional Branching- has already been coded
in preliminary form.  The structure of the software is such as to make this
a very easy to implement feature.

	By using a computer a bit larger than the minimum possible we  are
able to offer you these  existing capabilities, and potential growth  features
at very little increased  unit cost. We  find that it  has been unwise  to
milk a  small  8-bit microprocessor,  when  an  admirably  suitable  16  bit
machine like the LSI-11 offers such a greatly increased capability both in
processing ability and ease of programming.\.

				      PERFORMED			    TIME

Mechanical Design Layout-		1				.5
Detail Mechanical Design-			1-4				4
Build and Debug Proto #1-		2-6				2
Build and Debug Proto #2-		2-8				2

Controller Hardware Layout-		1				.5
Control Detail Design(Electronic)-	1-3				2
Build Controller #1-			2-6				1.5
Build Controller #2-			2-8				1

Software Concept Development-		1				.5
Operating Software-			2-5				3
Teaching Software-			3-7				3
Debugging Software-			4-8				1

System Assy #1 Proto-			6-7				1.5
System Assy #2 Proto-			8-9				1
Performance Tests #1-			8				1
Delivery #1-				9			
#2 Revisions-				8-10				1.5
Delivery #2-				11				

Hardware,Maint.,Assy. Doc.-		10-12				2
Software Documentation-			7-10				.5

Total-									28.5 man months

Material Costs.

Each Proto Arm System- 	$12,000

Total Material Costs-	$24,000

Additional Costs- $20,000 for development electronics and computer hardware and software.

All of the following features currently exist and have been demonstrated and 
delivered to customers.

1)Teaching in axis and world coordinates-	 	TRANS,HERE, WHERE commands
2)Trajectory controlled motion- ability to move
   in straight lines in ANY direction.-	 		DRAW command
3)Trajectory controlled motion- ability to move
   along polynomial or linear interpolated
   trajectories-controlled path motion-			MOVE command
4)Point to point motion-					GO   command
5)Two levels of precision-				COARSE command
6)Hand coordinate motions, useful for
   insertion and removal tasks.-				APPRO and DEPART commands
7)Ability to vary speed on an instruction
   by instruction basis.-					SPEED command
8)Multiple program selection.-				EXEC command
9)Looping features-starting at arbitrary
   points in program.-					EXEC command
10)Ability to insert or delete instructions-		I and D commands
11)Emergency Halt and Proceed Feature.-			Return and P commands
12)Saving of Programs and Taught Points.-		PUNCHP and PUNCHT commands
13)Touch-up of points.-					TRANS, HERE, Change? instructions
14)Stop on Error or obstacle feature.-			GRASP and Timeout features
15)Crash protection-halt in case of
   deviation from trajectory-				Timeout feature
16)Software limit stops-manipulator will not
   try to go where it can't.-				Req'd arm solution doesnt exist.
17)Universal software-will run any arm WITHOUT
   any revisions, just change calibration and
   geometry constants- easily done-			Transform concept stores data as
								cartesian and Euler coordinates.


Assumes batches of 100 systems.  No pattern or tooling costs or amortization included.
No engineering or materials overhead included.  Labor priced at $15/hr.

Prices are per EACH system.


Structure-	Base and Column-		$250
		Head Unit-			$100
		Links-			$200
		Joints-			$100
		Covers an Mounts-		$ 75
		Bearings-			$200
		Finishing,Detailing-		$100
		Wire Harnesses-		$100
		Misc.-			$ 50

	Total						$1175

Gearing and Housings-
		Gears-			$300
		Housings-			$300
		Bearings-			$180
		Shafts,fittings-		$100

	Total						$880

Drive Units-
		Motors-			$420
		Encoders-			$300
		Tachometers-		$120
		Brakes-			$ 50
		Housings-			$150

	Total						$1040

Assembly Labor-
		Drives-12hrs.		$180
		Gearing-12 hrs.		$180
		Structure-10hrs.		$150
		Wiring-10 hrs.		$150

	Total						$660

Manipulator Total-					$3755

		DEC LSI-11-		$600
		Memory-			$400
		Interface Cards-		$600
		Power Supply-		$100
		Backplane,Mounting-	$200
		Connectors-			$ 50

	Total						$1950

		Power Amplifiers-	$200
		Pre-Amps, Servo Cards-	$600
		Encoder Card-		$150
		Power Supply-		$200
		Backplane,Connectors-	$150
		Switches, Hardware-	$100
		Cabinet-			$100

	Total						$1500

Labor-Wiring and Assy.-40 hrs.		$600

Computer and Controller Total-			$4050

Teach Unit(one per 3 arms)-		$200
Software, PROMs and programming-	$250
Checkout and Test-30 hrs.		$450

TOTAL FOR COMPLETE SYSTEM.-	*******	$8705 *******

Extra for Cassette Unit-		$600
Deduct for 5-Axis system-	$500