Willow Garage PR2 User manual

PR2 Power Board
Remove/Replace Instructions
7/20/2010

PR2 Power Board Remove/Replace
Overview
Removing and/or replacing a PR2 Power Board is a difficult operation. There are man wa s
to cause injur to the user and/or damage to the PR2. Read entire procedure before
starting.
General Safety Instructions
•Alwa s wear an ESD wrist strap when reaching into the robot.
•Do not drop an screws into the robot. An lost screws ma cause the robot to
malfunction. If ou drop an screws into the robot, do not turn on the robot until ou
have contacted Willow Garage Support.
•When removing screws, save screws b t pe. You will need screws that ou have
removed when replacing the components.
•Use extreme caution when removing an cables. All cables are ver difficult to repair or
replace if broken.
If you ave any questions about using t is document, contact Willow Garage Support
before proceeding.
Pre-Start C ecklist
Before starting to remove and replace a PR2 power board, make sure ou have completed
these steps:
•Review instructions for “Robot Overview, Torque Tools, Loctite” and “Setting Torque
Driver”.
•Remove “Top Rear”, “Bottom Rear” and “Rear Bellows” covers.
•Raise spine to approximatel 25 cm from bottom. Do not raise spine to maximum
height. Use instructions in “Manual Spine Movement” document if necessar . (25 cm
height is about 80% of maximum height of the spine).
•Turn robot off. Disable main power breaker.
•Unplug robot from wall.
Required Tools and Materials:
•PR2 Tool Kit and PR2 Accessor Kit
•Replacement PR2 Power Board
•Grounded (ESD-safe) work surface

PR2 Power Board Anatomy
Refer to the following document for an component names for the main power board
components.

1. Make sure ou have removed the “Top
Rear”, “Bottom Rear” and “Rear Bellows”
from the robot. The spine should be
about 25 cm above bottom, or about 80%
up (see Drawing 1).
2. Remove the runstop bracket. Use a 3mm
bit on the T-handle wrench. There are
three screws (see Drawing 2). The
bracket will remain connected to the
robot with a short cable. After bracket
removed, secure the right side of the
robot. Do not allow bracket to hang b
the cable.
Drawing 1: PR2 with rear covers removed and
spine raised
Drawing 2: Remove runstop bracket. Approximate locations of screws are
marked.

3. Remove the screws securing the Power Board air duct. The duct is located on the
underside of the power board. Use the T-handle wrench and a 3mm torque driver. See
Drawing 3.
Drawing : Power board air duct screws.

4. Remove the fan cover below the air duct. Use a 3mm wrench to remove screws. You
will not be able to use the T-handle wrench to remove these screws. Instead, use a
right angle 2.0 Nm torque driver that is in our tool kit (see Drawing 4). There are six
(6) screws holding in the fan cover (see Drawing 5). Note that the screws on the side
are different than the rear, store them separatel .
Drawing 4: Remove fan cover screws using right angle torque driver.
Drawing 5: Six screws holding fan cover. Side screws are different than rear
screws.

5. Lower the air duct to allow clearance to the power board. You should have to lower the
duct b about 2cm (see Drawing 6).
6. Remove cable cover on left-hand side of the power board. The cover should slide up
and out (Drawing 7).
Drawing 6: Lower the air duct to allow power board removal.
Drawing 7: Cable cover on left side of
power board.

7. Remove all cables from the left-hand side of the power board (see Drawing 8). The
cable for the “c1” computer is difficult, ou ma will need two hands.
8. Remove cable for the runstop (see Drawing 9).
Drawing 8: Left side cable removal.
Drawing 9: Runstop cable.

9. Remove all cables on the right side of the power board. The order is not important for
the three small 48V power cables on the top right (shown in Drawing 10). All cables
should be removed from power board, except for cable that goes to runstop bracket.
The cable for the “c2” computer is low on the right side, and is difficult to remove (see
Drawing 11).
Drawing 10: Right side power cables.
Drawing 11: c2 power cable on lower right side of power board.

10. Check the voltage on the “Batter Suppl ” cable. Use a multimeter set to DC voltage
mode. MAKE SURE ALL CABLES ARE UNPLUGGED FROM THE POWER BOARD.
After all cables are unplugged, turn on main breaker. Check voltage reading from
“Batter Suppl ” cable on the left side of the robot (see Drawing 12). It should read
between 56V to 68V.
Drawing 12: Check voltage on Battery Supply cable. All cables must be
unplugged first.

11.Remove power board. Use a 3mm bit in the T-handle wrench to remove all six screws.
There are two screws on the bottom, two in the middle and two near the top. See
drawings 12, 13 and 14. Be careful to remove onl the correct screws. When removing
the last screw, ou will have to hold the power board in place to prevent it from moving.
Drawing 1 : Bottom screws for power board.
Drawing 14: Power board screws -middle row.
Drawing 15: Top screw for power board. Right side has
matching screw.

12.Remove power board from robot. Slowl pull on the right side of the board, gentl twist
it out, and pull back. Do allow an cables to catch on the board. See Drawing 15.
Drawing 16: Remove power board. Pull right side out first, then gently
pull left side. Make sure all cables are clear.

13.Place the removed power board onto a grounded work surface. Remove the wireless
runstop receiver. Note that international PR2's ma have slightl different runstop
receivers installed (see Drawing 16). Use a 10mm socket and the T-handle wrench.
14.Place replacement power board onto a grounded work surface. Install the wireless
runstop receiver. Use a 10mm socket with torque driver at 3.2 Nm.
Drawing 17: Remove runstop from power board. Use a grounded work surface.
Drawing 18: Replace wireless runstop receiver. Use grounded surface.

15.Insert power board back into robot. Insert the left side first, and guide the right side in
(see Drawing 18). Do not allow an cables to be trapped between the power board and
the robot frame. The power board should be held roughl b alignment pins. Replace
the six screws that were removed using a 3mm bit. Set torque wrench to 3.2 Nm.
Thread all screws before tightening an of them.
Drawing 19: Replace the power board.

16.Replace all cables to the power board. Start with the wireless runstop cable. When
inserting MCB power cables (on top-left of power board), make sure the correct cable
goes to the correct breaker, check cable labels to verif (see Drawing 19). For fan
cable on right side, fan must go into “Fan 0” slot. MAKE SURE ALL CABLES
SECURELY CONNECTED BEFORE PROCEEDING.
17.Attach air duct to bottom of power board. Use 3mm hex bit with torque wrench set to
3.2 Nm. There are two screws to replace. See Drawing 3 for screw locations.
18.Look at Drawings 4 and 5 to replace fan cover. Thread all six screws before tightening
an of them. Use the right angle torque wrench from the toolkit that is set to 2.0 Nm.
19.Secure the runstop bracket. Use a 3mm bit with a torque wrench set to 3.2Nm.
20.Insert cable cover on left side of power board. See Drawing 7 for removal picture.
Drawing 20: Replace MCB power cables. Check labels on cable and make sure they
inserted into correct slot.

21.DO NOT TURN ON ROBOT POWER. Make sure ou have completed all items below
before enabling power.
•All screws that were removed are secured into robot.
•All cables are connected to power board.
•Robot is unplugged.
Power up procedure:
•Make sure robot is unplugged from wall.
•Press runstop to disable motors.
•Enable main breaker on back of robot.
•The main fan should run at high power for several seconds, then slow down.
•All breaker lights on left side of power board should be orange.
•All lights on right side of power board should be green/red.
•Computer power and 12V lights should be on.
•“Status 1” and “Status 2” lights should be off.
Robot check:
•After computers boot, run “sudo pr2-s stemcheck”
•With runstop disabled, run “sudo robot start” and verif diagnostic status for power
s stem.
•Do not move robot or robot motors without covers installed.
After the robot has passed “pr2-s stemcheck” and the diagnostic s stem reports “OK” for the
power s stem, power down robot and attach all covers for the robot. After covers attached,
start up and shut down the robot several times and make sure it successfull boots each time.