by Chris Hechtl
His right arm was considered a BE, Below Elbow, by the prosthesis community. He was still figuring out a way to cram everything he needed to fit into the forearm prosthesis to allow him full range of motion and function. The fingers on his left hand were tricky; they were far too small. He'd set that problem aside for the moment.
The real complicated prostheses were the lower extremity ones. Trans-femoral on both legs. His research indicated they were difficult because of the knee's action. Normally someone who had one or both legs amputated at that area had to put out 80 percent more energy just to walk. Modern materials like carbon fiber, cables, microprocessors, and such gave back some of the lost range of motion, but they were very expensive.
Myoelectric was what he needed, but how to get it? And more importantly, the power? Neural would be better … he frowned, rubbed his head, and went back to the power issue. That was the biggest one. Once he had a basic power supply, he'd have to fit everything else in around it.
Power has always been the bane of prosthetics. Jack found it was indeed a real problem. Batteries were always limiting, limiting in how much they could handle and for how long. They also had to be recharged for long periods of time or the batteries had to be swapped out for fresh ones.
He briefly toyed with that idea before he discarded it. No, he had to find a way to scavenge for power while on the move.
Regenerative systems would do some of that, but there was of course a weight penalty. The more hardware he added, the greater the weight. There had to be something else.
Eventually he went back to his roots. He'd been toying with thermoelectric generators like a lot of engineering students. They were nanotubes that were created in the lab, then turned into a sort of felt that was layered and then sewn into fabric. They used the Seebeck effect, where one side was hot while the other was cool, to convert that differential into electrical energy that the user could then harness. It was cool to have them on campus, you could charge your electronic device with them. It was largely a toy. The fabric industry had tinkered with it for some time, but the cost was prohibitive and the material wasn't wash friendly.
He had been tinkering with them to help power skin suits for astronauts. Now he had another idea for them.
He combined the thermoelectric felt with tiny lithium-ion batteries to provide his power source. For the moment he would leave the regenerative system on the table.
When he was confident he had something, he used his home 3-D printer to print a modified schematic. He'd picked up the original from the web. There were several groups that had been working on the problem for decades through open source, but their efforts had been largely geared to low cost methods for children. Many weren't powered, so it had taken a bit of work to move around to get it right.
He test printed the components to one leg, using his uncle's size as the parameters. While it printed in the garage, he tried to focus on another part, but his fatigue caught up to him and he found himself drifting off. Eventually he gave in to the inevitable and caught a few hours of sleep on the bed.
His mother's return home startled him awake. He greeted her and ignored her good natured complaints about his lack of a hygiene as he ate the Chinese takeout she'd brought home. She listened patiently as he explained the project, nodding sagely until he fetched the plastic foot.
“You know there is no way that can handle his weight,” she observed.
He turned it in his hands, frowning thoughtfully. Finally he nodded. “I forgot that,” he admitted. He cursed himself for not remembering that provision in the descriptions. He'd had a lot on his mind, but that was no excuse.
“Yeah, I think you did.”
Jack frowned thoughtfully, turning the foot over and over in his hands. “Well, I can use this as a template. It's just my initial prototype anyway. When I get it right I'll … I'll make it out of carbon fiber or something.”
“Jack, the costs …”
“Hang the costs! I'll damn well do it!” Jack said, eyes flashing as he lunged to his feet. “What good is the money dad left me if I can't use it to help family?”
Ursilla sat back in surprise at her son's vehemence. Finally she blinked and then nodded. “Okay.”
“I'll … I'll set it up as a start-up. A business so I can write some of it off as an expense,” Jack said, pacing. Again his mother nodded.
“I suggest you get the ball rolling there. If not now, then in between prints. But first, a shower. Please,” she said, holding her nose.
He sniffed his armpit then couldn't help but laugh at her disgusted expression.
“Fine, fine,” he grumbled, giving in if not gracefully, then inevitably. He stalked off to shower and shave.
{D}==+===@E
The first three prototypes were failures; the range of motion didn't match his own. They also couldn't fit everything he needed to fit into them. He did learn to use springs to help return the limb to a neutral pose. That saved on power. An attempt to experiment with smart memory alloy muscles and artificial tendons proved interesting, though his first try had been a smoky black mess. Too much amperage for the tiny hair thin wires to handle. He'd ended up with a small muscle, but the cost had been prohibitive. It had also proven not as strong as he had hoped, so he abandoned the project.
In between the prints, he dutifully handled the paperwork for the business side. He called it Lagroose Limbs Inc., even setting up a website to get hits on ideas. He was amazed by the traffic he picked up right away. Not all of them were from amputees either. Some people were interested in replacing their body parts with artificial—becoming cyborgs. It was disturbing but interesting. So were some of their posts.
He had already pulled apart every piece of open source artificial intelligence he could find. He pulled up his templates and files and then used what he learned to make a custom software package for the electronics. Not only would it learn, but it would also adapt, programming itself as Ed went through with his life. At least that was the theory anyway.
He really couldn't call the software package true intelligence; it was far too primitive to be intelligent. Its neural network wasn't even up to that of an insect, though he had packed in plenty of space for it to grow or be updated if needed. Besides, there was no social interaction, and who would want that? Talking to your arm? Legs? It was a silly idea.
Exploring the software was interesting, however. He had dreamed of a true artificial consciousness like a lot of engineers. To date no one had gotten one, though many had tried. Lately it was almost as if they'd given up. Or they had come to realize that if they did make something, a consciousness, a person, it would open a lot of thorny ethical questions. Fortunately, the computers hadn't crossed that threshold on their own yet either.
If he were to get the osseointegration going on Ed, he had to have a viable plan in the works now, before the scar tissue healed over completely. They had even stopped treating the scars with ECM, extracellular matrix. His mother had been growing Ed's stem cells and skin grafts in the company's biogen reactor and had expanded to ECM until she'd gotten caught. The company had reprimanded her severely and put her on paid leave pending a review board. She'd accepted it quietly.
For Jack, it meant his mother was home. She tried to divide her time between Seattle and San Francisco though. He knew it was to give him space. But he had to admit when she was around it made it easier. Not only did he need a keeper due to his single-minded obsession, but her medical background helped him from time to time. At the very least, it had put him in contact with a few specialists in the field.
Ed had been a jogger, but to get around the major disadvantage of osseointegration, the implanting of a titanium rod into the remainder of each of his femurs, they had to find a work-around. Otherwise, when he put any stress on the limb, it would break the bone.
To counter that Jack worked out a design for the titanium rod that would compress slightly. He also extended the rod's length right to his hip joint and included a titanium hip joint re
placement there. That would allow the weight to be distributed without breaking the bone. It would also allow him to keep the bone, though he would lose some room for his bone marrow.
Ursilla was concerned that marrow and blood vessels would attempt to grow into the titanium cells Jack had created to absorb the shock of running. Jack was more concerned about tissue encapsulation or rejection, but he did his best to ease his mother's fears by running some simulations.
The surgeons who had amputated his legs had done a good job, even taking care to protect his nerves and cluster as much of the nerves into the stump as possible in case of future need. Jack had planned to use myoelectric sensors on that portion of the stump to sense the nerve pulses and trigger the microprocessors, but he realized they could take it one step further if they weaved in a neural implant graft to pick up the signals from the nerves and then translate them into software commands for the microprocessors.
He put that on his list and then went to work refining his leg design. When he was finished he packed it all up and drove down to San Francisco with his mother. They presented it to Ed, Prue, the lead therapist, and doctors. Prue and the doctors seemed skeptical. They were, however, very impressed with the artificial limbs. The doctor was concerned about not trying the socket system first.
“I passed that over because of the problems with it. The socket has to be made perfectly, without air bubbles. And you still get rashes and problems,” Jack said gruffly. “Look, I know it will work.”
“I understand you think it will, and your computer models look solid. But it's one thing to do it in a computer … real life is quite different young man,” the doctor replied patiently.
“Look, I know this is a risk. But I'm trying to give you a chance to get your life back, Uncle Ed. What do you have to lose?” Jack asked. He was glad they had taken him off the respirator and closed his trachea tube. He still had to be fed from a tube in his stomach, however.
Ed's good eye looked around the room then settled on Prue. Prue looked at him.
“Can we do it?” Prue finally asked, turning to the doctor.
“Ordinarily, I wouldn't countersign this. But he is stable, and his constitution is good. Everything you are proposing has been done before, so there are no medical ethics. I do know, however, that the cost of the surgeries alone will be high. And the recovery time will be high as well,” he said heavily. “Your insurance won't cover it I'm afraid.” he said as if that was that.
“They might not, but I will,” Jack said firmly. Prue had been looking at her husband with resignation; she turned sharply to turn to stare at her nephew. “Doc, if Uncle Ed is willing to play guinea pig, I'm willing to help him.” He turned to the man who had taught him poker while camping. “What do you say, Uncle Ed? Time to fold or time to risk it all?”
Ed's eye bored into him, right down to his soul. Jack stood there, frozen, unable to breathe, unable to move. Finally Ed jerked his right arm, then his left. He couldn't nod or work his jaw, but he could salute with the remains of his left hand.
“I think that is a yes,” Prue said with tears in her eyes. She reached out to touch her husband's bicep ever so gently in support.
“I'll draw up the paperwork. We'll start the preliminary work now. I'll brief the surgery team, and we'll get them here to go over this design,” the doctor said.
“I understand the titanium will need to be sterilized properly,” Jack said.
“Six-million-dollar man,” Ursilla murmured softly, hugging her son from behind. She ruffled his hair.
“Not quite. He won't be a superman. I am working on an exosuit to get around his current mobility problem,” Jack said, looking at Ed. He studied the damage and the cage. “My problem is the spinal damage. I've been trying to figure out how to make it work. The medical reports stated you fused some of his vertebra together and pinned others together to handle the damage?” Jack asked, turning to the doctor. The doctor nodded. “So his range of motion has been limited.” Again a nod of reply. “You can move him in this rig. I wonder if there is a way to … no, I don't like the idea of any vibration translating into the frame.” Jack frowned and rubbed his jaw as his mind turned over the problem.
“One thing at a time. The surgery first. Who knows, you may find out that he won't need it.”
“Oh, he'll need it. For the therapy at least,” Jack muttered.
{D}==+===@E
Jack watched nervously as the surgical crew went to work. He winced as they tested the bone saw and drill. He crossed his arms and paced in the observation room.
“I don't think you should be here for this,” Ursilla urged quietly. Prue had gone home to be with the kids. She couldn't handle the blood anyway. Ursilla was feeling squeamish herself, and she was a trained medic.
“I have to be.”
“Penance?” Ursilla asked, looking at her son. He didn't answer for a long time, just paced.
“I don't know,” he finally answered. “Maybe.”
“Guilt isn't going to help. You didn't put him here. You are trying to help.”
“Am I? Or am I making it worse?”
“We'll find out. He's agreed, Jack. Remember that. He knows the risks.”
“Yes, but is he counting on the risks to die on the operating table? I keep asking myself that question.”
“Ask him when he wakes. I wouldn't. I'd treasure every moment with him. If I could have been here for your father …,” Ursilla closed her eyes. Jack looked down at her, so small in her seat. He went over and rubbed her shoulders. She reached up and patted his hand in mute reply.
The surgery would be in stages. Two teams were at work: one adding the titanium to his left leg while the other worked on his right. They were going to work on his right arm and left hand at a later date.
Jack watched grimly as the surgery went on for hours. They were careful to drill through the bone and insert the rod. The rods had cost him …, he snorted at himself, an arm and a leg? Was he really going to think that? He shook his head at his black humor. Well, if it worked it would give his uncle a new pair of legs.
He'd finally figured out a way to get around the finger problem. He had adapted the design of the right hand to the left, mirroring it. Then he'd altered the base attachment points to allow them to be attached to titanium rods. Small pockets would allow wires to go through his body into a cavity in his abdomen. He would be able to use induction to recharge the battery if the thermal generator ran too slow for his tastes.
The fingers like the arm and legs had artificial tendons of his own design. He hoped they would work. Only a field test with Ed would prove it one way or another. His tests couldn't tell him if they would be comfortable long term.
A soft knock on the door made them turn. “Hi, um …,” a young man, in his late twenties came into the room. He was clean cut with a green army uniform on. A brass tag on his left lapel said Murtough. The single bar on his collar told them his rank was that of a lieutenant. “I understand Ed Lagroose is here? More surgery?”
“Yes. We're trying to give him a measure of his life back,” Ursilla replied after they had shaken hands. “You know my brother-in-law?”
“Yes. We did some work together. I liaisoned with him, and he returned the favor a time or two.” the rather young lieutenant said as he studied Jack thoroughly. “I'm sorry, are you his son?”
“No, my son. Jack Lagroose,” Ursilla stated smoothly.
“I see.”
Jack turned back to see the surgeons fitting the hip joint. That had been tricky; they'd had to do a CT scan of his hips to make an accurate model for the titanium. But it was going in smoothly. From his view of his uncle's biosigns, he was stable and in a deep sleep. “It's going good. I think the left leg will be wrapped up shortly.”
“Well, they started earlier,” Ursilla murmured, glancing out the glass and then back to their visitor.
“It will take time for the swelling to go down, and then more time for the bones to grow into the implants. Damn it.�
�
“Patience, son. He can test your design in time.”
“Your design?” the lieutenant asked in surprise.
Jack turned to the starched green uniform. He nodded curtly.
“You're an engineer?”
“He has several master degrees in engineering, business, and space exploration. He was working on his doctorate,” Ursilla replied. “Though I had hoped he would chose medicine,” she said with a hint of teasing in her voice.
Jack sniffed.
“Who knows. You may have found your calling here, son. If this works …,” she left the idea hanging.
Jack shrugged. “Like you said, Mom, patience. We'll have to wait and see. Six-million-dollar man and all that.”
“Wow,” the lieutenant replied with a wide eyed expression. “Even his eye?”
“I'm still working on that. There are techniques to attach the nerve clusters in the eye to a board. It's been done for years. But they've been doing it one photo cell at a time. I want to change that approach and automate it as much as possible, if possible,” Jack said absently.
“Automate it?”
“Robots can do some surgical procedures. And have you ever seen them handle electronic manufacture? Hooking up electronic connections to a chip? It can be amazing. But a person doing that would take ten times as long to make each connection.”
“Yes, true, but getting a robot in there is tricky. I mean, it's the eye and all,” the lieutenant replied, pointing to his left eye.
“Then we pull it out,” Jack said with a shrug. His mother stared at him. The lieutenant blinked as his jaw sagged open. “People have had their eyeball come out of the socket. In this case he has no eyeball in the socket, so it's not a problem,” he said with a shrug. “But for others, pull it out. Replace it if needed or bridge a problem. I'm not the expert.”
“Obviously. Or it would have been thought of and done before,” Ursilla said dryly.
“Nothing is ever as easy as one likes to have or says it will be. It's never that cut and dried,” the lieutenant replied.