Robosapien Hack Update
by GARY LAVARACK
 Continuing on with our modifications, we will next tackle the special attention that has to be given to the shoulder springs for the arms. They are attached to the back chest plate. Study the construction detail and notice that the screws for the springs do not have to be removed. Now, remove the screws for the back chest plate, carefully being aware that it will be connected to the motherboard and the arm springs to the shoulders. Simply raise up both arms to lessen the tension on the springs as you remove the back chest plate and un-hook the springs from their tabs. Before unplugging anything, make a note of the plug orientataion notch, which is usually at the top and also that the plug devices have two locking tabs incorporated in both the male and female components, and if you are not very careful to separate these locking tabs from each other, you can pull off the whole assembly from the motherboard. I used a very small flat head screw driver to gently pry up the hold downs on the female motherboard part and then pulled out the male plug unit. If you accidently pulled the whole thing off the motherboard, don't panic, simply separate the two units with the small screwdriver and replace the motherboard part, making certain to notice the orientation of the correct allignment notch, again, usually at the top. Once pulled out, I used a #11 X-Acto blade to scrape off the tabs on the male plug part to make re-assembly and removeability easier for the next time around. Under-standing this, unplug the on/off switch and speaker leads from the motherboard and set aside the back plate. Do the same for the crotch plates, starting with the rear screws first. Notice the very generous space inside both of these areas for our LED lighting units.
After disassembling the icicles, I found that the whole red, green and blue LED unit is completely self-contained and quite small, about the size of a quarter. Since the icicles were originally to be placed on a tree, the dark green lead wires between the 6 units is quite long. I de-soldered these wire leads because they were very stiff and I wanted to use a more flexible smaller wire to snake through his body. When powered up, they randomly and slowly rotate through the full spectrum of light giving off a wonderful illusion to the skin. I decided to place them everywhere inside his head, body, legs, feet and even the arms and hands. Checking the nicely identified printed circuit board quickly revealed where to pick up the proper voltage and ground.
Let's discuss putting the LED's inside the palms of the hands. Starting with the exoskeleton upper arm halves, they come off without having to remove the chest plates. Again a very neat design. The upper arm halves are hollow structural components of the whole upper arm assembly. Please notice that the black conduit tubing, which houses the finger control cable and electric wires is supported by the two halves of the chest plates and other end by the two halves of the hand. Handle this tubing carefully so as not to crimp any of the wires or cable. Remove the front upper arm plate first and you will notice the back arm plate remains in place with the body. The back half is mounted on the shoulder gear/motor output shaft and the other end supports the wrist pivot shaft. I immediately wrap a piece of masking tape around the shoulder area to hold it in place. The wrist/hand can now be slid off the support pin at the lower end of the upper arm. Remove the hand and place it on a 6" high small box support to releave any tension on the cable. The hand is a heavy duty work of art. Removing the three self-tapping hand screws and you will notice that the two halves do not immediately come apart. Another small challenge is removing the black ring at the end of the tubing cable right at the wrist area. It is a coupling that holds the two halves of the hand together and, unfortunately it is glued in place, but not too badly. I put four layers of masking tape on my pliers, to prevent maring the ring surface. I gently twisted back and forth radially to break it loose, then it pulled off easily and slid up the cable to keep it out of the way temporarily. Be very careful of that cable tubing!
Position the hand on the box support so that you will remove the outside plate first, or in our case, the upper half first. The motor and electronics are mounted on the inside plate, or the lower half. There is a knurled metal pin that runs from left to right as the pivot point for the three fingers, and to add structural integrity to the hand. You can see the ends of the pin on both sides of the hand shell. Initially I thought to simply tap it out. This will not work because of the knurling grabbing the plastic housing. It is designed not to fall out, and this presents a challenge for separation. Now sneak a very broad flat head screwdriver into the palm seam and gently twist. As this twisting slowly separates the two halves, you will begin to see the knurled pin. Gently working around the perimeter of the hand, begin to pull the two halves apart, but don't try to go all the way. At this point take a pair of flat nosed pliers, as opposed to needle nosed pliers, and instead of squeezing them closed, place them into the partially opened seam and pry the two halves apart by pulling outward on the handles. This will give you a very nice mechanical advantage in controlling the separation of the two halves. As the two halves come apart you will hear a snap. This is the finger control cable being pulled inward out of its mount by the straightening springs in the fingers. It sounds terrible, but nothing will be damaged.
The hand and fingers are an elegant design and I never really cared for the clumsly looking sensor rings. Separating the sensor rings is tedious. The small printed circuit board is hot glued to the housing. Do what ever is necessary to free it up, being extra careful not to crack it. The sensor connector is the white one, with the brown wires. If it is all gooped up with hot glue, like mine was, pull off the whole white connector, clean it up and then replace the motherboard side. In this way, if you ever decide to re-install the sensors you will have no problems. First remove the main side screw, the one nearest to the motor. The three fingers must be removed to reveal the hidden screws for the sensor mount. Mark the three fingers, index, middle and pinky before you loosen the screws. Remove the two hidden screws, the unit is now free. Replace the three fingers, gently pull the tubing/cable back into the correct position and close up the hand.
The three black rubber palm grippers unit simply lifts out of the bottom half. I removed the middle rubber gripper from the white plastic, milled out the opening to accept the three LED's and then directly connected the leads to the motor connectors. Because the motor circuitry reverses the polarity, the LED's only come on in one direction of the wrist rotation. I mounted another set of LED's to the area where touch sensor was located, wired these with opposite polarity so they come on when the wrist twists in the other direction. The effect is kind of neat.
Noticing the space inside the upper arm, you can easily install the rainbow LED's inside the arms too. Pick up the electrical connection for your lights from the motor connectors. Snaking the wires up through the wrist will require you to drill some holes. You'll have to decide the best location for these. The legs are very simple to open up. Massive space is inside for whatever amount of LED's you would want to put in there. The problem to overcome with the LED install inside the legs is where to pick up the power. If you connect directly to the batteries lead to the rest of the body your lights will be on all the time. They will not react with the on/off switch on his back. You'll have to back snake the switchable leads from the chest area down and through his legs. Alot of work. To solve this problem, simply install a small skin mounted on/off slider inside his thigh. Problem solved.
Mounting the "eye" LED's in his face shield presents unique challenges. The mouth sound sensitive LED's require the Velleman Mini Kit MK103 LED Sound-to-Light unit to be mounted inside his chest and the wires run up through the neck for the LED's. The head is jambed packed with alot of electronics and electro/mechanical devices to move the blue eyes. The dark transparent back helmet plate is glued in place but it also has two tabs on either side to snap it back in place. I think that the reason it is hot glued was because the design of these locking tabs did not grip very well. So they solved the problem by hot gluing it. Squeeze the longer dimension inward to release the tabs and work a dull knife in and around the edge to work loose the hot glue connection. It doesn't come off hard. Be careful not to mar the plactic too much.
The head shell is comprised of three pieces plus the eye transparent shield. Four screws are located on his left side. Be careful now, there is alot going on inside there. You must be very careful. Study everything. For me to describe taking apart the head would take volumes. Work slowly and take notes as to how it all comes apart, so you can re-assemble the mechanism. It is that complicated and small. The front dark face shield comes off as you separate the head halves. The mouth area is a separate component, the third part of the head. Realize the as you separate the head components it is now loose from the neck. It turns into a real nightmare at this point to try and hold everything together. Good luck here.
Drill two holes of the proper size for the LED's and run the wires down through the neck to pick up the power from the controller motherboard for the eyes. Now decide if you want one, two, three or four LED's for the sound-to-light mechanism. The reason I mention that you have to decide how many at this time is this: the LED's that are designed to be mounted on the printed circuit boad of the Velleman kit are wired in series. This means that if you choose to use only one LED, the other three must be properly wired on the printed circuit board for the circuit to work properly. I put all four in his mouth position. Kind of like a horizontal star, two holes in the middle up and down and one each at the corners of his mouth.
Putting in the cell phone camera was a real challenge. I decided not to mount it inside his face shield, but instead mounted it on top of his head. Made everything alot easier. The real difficulty was making the ribbon cable longer to reach down through his neck to the "guts" of the cell phone and the LCD monitor. It was comprised of twenty wires each of which was redicuously small. The twenty pin connector was only 1/16" x 3/16". I could not find anyone who made a pin or ribbon cable that small. So I very, very carefully cut the ribbon cable on a long diagonal, separated each wire by cutting in between the ribbons, decided how long I needed the extension and hand soldered each of the twenty wires with varnish coated coil wire. A real pain. But the effect was well worth it. When the viewer see's himself in the LCD monitor it gets a real nice reaction from everyone. I understand the Robosapien V2.5 or V3 will have a camera already mounted. We'll have to wait and see. I used the battery from the cell phone to separately power the camera rig with a separate switch mounted on the body. Have fun and I'll talk to you again next time.
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