OWEN Walking Robot Install Guide
The 3D printed parts are as follows:
- Left Foot
- Right Foot
- Ankles (both are identical)
- Pelvis
Servo, arm, and screws:
FIRST STEPS
Connect the battery to the ODROID-C0. Connect a 2.5mm 5V/2A power supply to the C0. The
green light should come on indicating that the battery is charging. Turn the C0 off if it isn't already.
The green light should remain on indicating the battery is still charging.
ANKLE ASSEMBLY
First, install the servo arms into the ankles. The ankles have a mark pointing to one of the slots. This
slot is for the black arms (the metal gear servo arms), while the unmarked slot is for the white servo
arm. Use the shortest arm that only extends on one side of the servo axle collar.
Some trimming may be needed to fit the arm in. If this is the case, hold the arm with a pair of small
pliers and shave the sides with a razor blade testing each cut until it fits snugly. The side of the the
servo arm that has the teeth in the servo axle opening should be facing the flat side of the ankle (the
side opposite of the mark). Push the servo arm all the way through until the axle collar is touching
the ankle. This can then be glued into place, or a piece of wire like a small paperclip can be bent to
fit through two of the holes in the servo arm. This will keep the ankle from coming off the servo
arm.(see figure above)
Next, install the white servo arm from the opposite side as the black arm, again with the toothed
portion of the collar on the servo arm facing the flat side of the ankle. Secure this arm the same way
as the black arm.
For the other ankle, do the exact same procedure, but opposite. It should be a mirror image of the
first ankle.
Do not mount the ankles to the servos until instructed later.
FOOT ASSEMBLY
On the foot, the wider portion is the outsole, and the side with the larger 45 degree beveled edge is
the back.
Take a black servo (metal gear) and put the servo wires through the opening between the risers near
the front of the foot. The bottom of the servo should then be inserted first through the opening with
the side where the wire exits the servo toward the outsole of the foot. Secure the servo to the riser
posts with the two included screws.
Do the same operation for the opposite foot.
PELVIS ASSEMBLY
The portion of the pelvis with the battery holder is the back, and the flat part is the bottom.
Insert the wires of one of the blue servos (plastic gear) from the bottom of the pelvis through the
opening in the top of the pelvis closest to the front. Insert the servo with the axle pointing down and
toward the front of the pelvis. Secure the servo with the two included screws.
Perform the exact same installation procedure for the second pelvis servo.
ODROID INSTALLATION
These instructions apply to the ODROID-C0. OWEN can also use the ODROID-C1, C1+ or C2, but
the ODROID-UPS module must be added to provide battery power.
Before installing the C0, it is necessary to solder the GPIO header to the C0 first. It is also
recommended to solder on the USB ports.
Install the C0 with the USB ports facing up and the top of the board facing the front of the robot.
The two mounting holes on the pelvis should match up with the mounting holes on the ODROID.
Secure the ODROID to the pelvis with an M3 screw and nut or riser.
If you have a USB WiFi module and an eMMC module or microSD card, you can install that now.
SERVO CONTROLLER INSTALLATION
Install the servo controller on the GPIO pins. The servo controller's connector should be flush with
the bottom-most pins on the ODROID.
SCREEN INSTALLATION
Install the screen on the pass-through header on the servo controller. The buttons on the screen
should be at the top.
BATTERY INSTALLATION
Place the battery in the battery holder at the back of the pelvis with the connector wire facing up.
Connect the connector wire to the C0. It is recommended to charge the battery during installation if
possible. This will give OWEN more run time after installation.
SERVO WIRE INSTALLATION
The servo wires can be routed through the body and pelvis of the robot to keep slack to a minimum.
However, make sure to leave enough slack in the wires to allow full range of motion for the servos.
Connect the servo wires to the servo controller with the brown wire on the servo connector closest
to the servo controller, and the orange wire on the servo connector toward the front of the robot.
Starting from the robot's left most servo controller connector, connect the servos in this order:
- Left hip
- Left foot
- Right hip
- Right foot
SERVO ARM INSTALLATION
Flip the switch on the C0. The servos should initialize. Turn the C0 back off.
Connect the white servo arms of the ankles to the pelvis servos facing directly away from each
other, and with the black servo arms facing forward. In other words, the left hip servo arm should be
facing directly to the left while the right hip servo arm should be facing directly to the right.
Because the servo arms have splines on them, you may not be able to get them exactly
perpendicular. Don't worry about this as you'll be able to adjust the servos later.
Connect the foot servos to the black servo arms, trying to have the feet as level to the ground as
possible. We will adjust these later as well.
Connect the servo arms to the servos using the provided screws.
IMAGING THE CARD
If you didn't purchase the preimaged eMMC or microSD from ameriDroid.com, you will need to
image it yourself. You can download the image from
http://video.respectech.com:8080/video/imgs/robot-owen.zip. Decompress the image and write it to
your media using the instructions at http://ameridroid.com/p/faq. The password for the above
distribution is "odroid2430".
Now that you have an imaged media card, insert it into the C0.
STARTING THE ROBOT
Turn on the power switch on the C0. It is normal for the servos to "chatter" until they are adjusted
properly. The screen will be solid white and then solid black until the booting process is completed.
Once the robot finishes booting, it is recommended to connect a keyboard/mouse to the robot so we
can get everything set up. A wireless keyboard/mouse is preferred as you won't have to have cables
coming off the robot.
Click on the network icon by the clock at the bottom of the screen and connect to your WiFi access
point. This can sometimes be a bit tricky on a 240x320 resolution screen.
Once the connection is made, open up a terminal (like LXTerminal) and double-click the top bar of
the window so that it fits itself to the screen. Type:
ifconfig | grep Bcast
Make sure to type the capital "B" and everything else in lowercase.
This should display the robot's IP address. From another device on the network
(tablet/phone/laptop/desktop/etc.), open a browser and type:
http://1.2.3.4
Replace 1.2.3.4 with the portion listed after "inet addr:" in the ifconfig results above.
You should now be greeted with the robot's control interface in the browser.
Scroll down to the calibration settings. Adjust the servo positions until both feet are level and facing
directly forward. When they are set correctly, there should be no chattering coming from the servos.
Once you are happy with the servo calibration, click the "Calibrate" button.
There are a number of pre-saved functions you can play with. These can be executed by clicking on
them. There are also load and delete options that can be selected before clicking on a button in order
to load or delete the function linked by the button. Please note that most functions are built on other
functions in the list.
OWEN Walking Robot Programming guide
First lets get your familiar with the layout.
This is the first thing to encounter. The status, speed, and movement programming.
The movement programming will be the main thing you
modify in these settings but the speed can also be adjusted for
special effects.
The Calibration settings is where you should have adjusted the
feet position when setting up Owen.
The movements are clickable commands. These hold the
programs you write in the Definition box.
If you click load before you click a command button, it will just
show you the code and not execute it.
Click 0-Start-Face if the face is not up on the screen yet.
Let's take a look at WiggleFeet
As you can see, there are 4 numbers. These numbers represent the Left Hip, then the Left Ankle,
Right Hip, and then Right Ankle all in that order. If we wanted Owen to twist his ankles we would
change the 0 values in these positions: [* 0 * 0]. If we wanted him to move his hips we would
change the 0 values in these positions: [0 * 0 *].
Lets look at another movement. 2-
HokeyPokey. This movement is made up
of 2 different moves, 1-HokeyPokey-Left
and 1-HokeyPokey-Right.
This mean that 2-HokeyPokey is running
the left side then the right. Other command
definitions can be specified by using the %
sign in front of the command name.
If you want to use another movement in your program use the % first, then spell out (case sensitive)
the other program name.
1-HokeyPokey-Left is made up of several
things.
%TipOnFoot2-Left
%WiggleFoot-Right
%WiggleFoot-Right
%0-Reset
Here looking at TipOnFoot-Left we can see the raw
servo positions that should be sent to the servos.
This also goes for WiggleFoot-Right.
Guide for calling a command.
4 numbers with spaces in between brackets is to change
the servo position. [0 0 0 0]
A star * in the brackets means to leave the previous number alone and not to change the position.
[100 * -500 *]
A % is used to call other commands, like %0-Reset
Speed is used to change how fast the servos change position. Example:
speed 10
speed default
wait is used to delay before executing the next command. This is very useful because if the robot
gets commands too fast, it may skip some to try to catch up. So slow down your command spacing
if necessary. Small delays like wait .8 are a good place to start if your motion starts jumping code.
Now try it yourself!
Advanced Users
As you look through some of the commands, you may notice that the underlying Linux subsystems
can be accessed through the command interface. This opens a world of possibilities for adding new
features.
For instance, all the following things and more should be possible if you want to pursue them:
• Voice synthesis
• Music playback
• Voice recognition and control
• Retrieving data from the web
• Interlinking OWENs using networking commands
• Facial recognition
...and more!
Some of the above will require extra hardware like a bluetooth speaker or a webcam, but they are
all possible.
The entire OWEN system is open source, so feel free to connect to OWEN via an SSH terminal to
look around and play with things.
OWEN runs an open-source lighttpd webserver, and most of its functionality is provided by the
Rebol3 scripting language, which is also open source.
When you do something cool with your OWEN, send us a video or email at
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