News
“Smart skin” can identify weaknesses in bridges and airplanes using laser scanner
Recent research results have demonstrated that two-dimensional, on-demand mapping of the accumulated strain on metal structures will soon be a reality thanks to an engineered “smart skin” that’s only a fraction of the width of a human hair. By utilizing the unique properties of single-walled carbon nanotubes, a two-layer film airbrushed onto surfaces of bridges, pipelines, and airplanes, among others, can be scanned to reveal weaknesses in near real-time. As a bonus, the technology is barely visible even on a transparent surface, making it that much more flexible as an application.
Stress-inducing events, along with regular wear and tear, can deform structures and machines, affecting their safety and operability. Mechanical strain on structural surfaces provides information on the condition of the materials such as damage location and severity. Existing conventional sensors are only able to measure strain in one point along one axis, but with the smart skin technology, strain detection in any direction or location will be possible.
How “Smart Skin” Technology is Used
In 2002, researchers discovered that single-wall carbon nanotubes fluoresce, i.e., glow brightly when stimulated by a light source. Later, the fluorescence was further found to change color when stretched. This optical property was then considered in the context of metal structures that are subject to strain, specifically to apply the property as a diagnostic tool. To obtain the fluorescent data, researchers applied the smart skin to a testing surface, irradiated the area with a small laser scanner, and captured the resulting nanotube color emissions with an infrared spectrometer. Finally, two-dimensional maps of the accumulated strain were generated with the results.

The primary researchers, Professors Satish Nagarajaiah and Bruce Weisman of Rice University in Texas, have published two scientific papers explaining the methods used for achieving this technology and the results of its proof-of-principle application. As described in the papers, aluminum bars with holes or notches in areas of potential stress were tested with the laser technique to demonstrate the full potential of their invention. The points measured were located 1 millimeter apart, but the researchers stated that the points could be located 20 times closer for even more accurate readings. Standard strain sensors have points located several millimeters apart.
What Are Carbon Nanotubes?
Carbon nanotubes (CNTs) are carbon molecules that have been structurally modified into cylinders, or rather, rolled up sheets of carbon atoms. There has been some evidence suggesting that CNTs can be formed via natural processes such as volcanic events. However, to really capitalize on their unique characteristics, production in a laboratory environment is much more efficient.
Several methods can be used for production, but the most widely used method for synthesizing CNTs is chemical vapor deposition (CVD). This process combines a catalyzing metal with a carbon-containing gas which are heated to approximately 1400 degrees Fahrenheit, triggering the carbon molecules to assemble and grow into nanotubes. The resulting formation resembles a forest or lawn grass, each trunk or blade averaging .43 nanometers in diameter. The length is dependent on variables such as the amount of time spent in the high heat environment.

Besides surface analysis, carbon nanotubes have proven invaluable in many research and commercial arenas, their luminescence being only one of many properties that can improve and enable other technologies. Their mechanical tensile strength is 400 times that of steel while only having one sixth the density, making them very lightweight. CNTs also have highly conductive electrical and thermal properties, are extremely resistant to corrosion, and can be filled with other nanomaterials. All of these advantages open up their applications to include solar cells, sensors, drug delivery, electronic devices and shielding, lithium-ion batteries, body armor, and perhaps even a space elevator, assuming significant advances overcome its hurdles.
Next Steps
The nanotube-laced smart skin is ready for scaling up into real-world applications, but its chosen industry may take time to adopt given the general resistance to change in a field with long-standing existing technology. While awaiting embrace in the arena it was primarily designed for, the smart skin has other potential uses in engineering research applications. Bruce Weisman, also the discoverer of CNT fluorescence, anticipates its advantages being used for testing the design of small-scaled structures and engines prior to deployment. Niche applications like these may be the primary entry point into the market for some time to come. In the meantime, the researchers plan to continue developing their strain reader to capture simultaneous readings from large surfaces.
Elon Musk
Grok Bot users hit with weekly limits early, Elon Musk explains what happened
Elon Musk said weeks ago during SpaceX’s third-quarter earnings call that the company’s Grok Bot, its autonomous AI Agent platform, was showing “the fastest growth of a product” that he’d ever seen in his life.
Now, SpaceXSI is scaling back Grok Bot users’ weekly limits, much to the surprise of those who have relied on it to take away monotonous tasks in their lives.
Elon Musk’s terse November 1 reply on X captured a sharp tension in the early days of agentic AI. Responding to a user who asked for a Grok Bot usage reset after hitting 100 percent with four days still left on the weekly cycle, Musk wrote: “The cost of serving Grok Bot was unsustainably high relative to revenue.”
@DogecoinNorway The cost of serving Grok Bot was unsustainably high relative to revenue
— Elon Musk (@elonmusk) November 1, 2026
The post arrived amid a wave of similar complaints from paying subscribers whose meters had jumped unexpectedly toward or to the limit, sometimes overnight and with little corresponding activity. It also stood in clear contrast to statements Musk had made only days and weeks earlier.
On the SpaceX third-quarter earnings call in mid-to-late October, Musk had described Grok Bot in almost the opposite terms. He called it “the fastest growth of a product that I’ve ever seen in my life” and said he had “never seen anything grow this fast.”
Company figures put paid weekly users at roughly 800,000 earlier in the month, more than doubling over the prior period. Daily active users had climbed from under 100,000 in early September to over 600,000 by late October.
Musk emphasized that the product has no free tier and that users appear to be getting real value beyond what they pay. In other remarks, he noted that usage per user was rising rather than declining, the opposite of the usual decay pattern for new software.
Grok Bot, launched around August, functions as an always-available agent with its own persistent cloud computer; it can schedule, research, shop, browse, and execute multi-step workflows even after the user steps away. Access is bundled into X subscription tiers (roughly $30, $100, and $200 per month) and certain Cursor plans, drawing from shared weekly usage pools whose exact sizes have not been publicly detailed.
The economics of that model are what Musk’s November 1 post put in the spotlight. Agentic systems burn far more compute than ordinary chatbot exchanges. Each task can trigger repeated model calls, tool use, web actions, and sustained background work.
When growth is as rapid as Musk celebrated, the absolute compute bill scales quickly even if average revenue per user stays fixed under flat monthly subscriptions. Industry observers noted the opportunity cost as well: the same GPUs can be rented to other AI labs at higher rates.
A simple back-of-the-envelope comparison circulating after the post illustrated the gap: if every reported daily user paid the top tier, annualized subscription revenue would still be modest relative to the scale of compute infrastructure SpaceX is building and leasing to companies like Anthropic.
Some users also reported possible dashboard anomalies around the same period, though Musk’s framing treated the underlying cost-revenue imbalance as the core issue rather than a pure metering glitch.
The juxtaposition is the core of this exchange. Within roughly two weeks of publicly framing Grok Bot as an unprecedented success with strong unit economics and no free tier, Musk acknowledged that serving the same product had become unsustainable relative to the revenue it generates.
For the broader industry, the episode underscores a structural challenge of the agent era: demand is real and growing faster than many expected, yet the cost of fulfilling that demand through always-on, multi-step agents can outrun subscription pricing before companies can adjust limits, introduce metered billing, or raise prices.
Musk’s reply did not promise an immediate reset or higher allowances; it simply stated the constraint. In doing so, it supplied a rare, explicit public data point on the unit economics of a high-profile AI agent just as adoption numbers were still being celebrated as the fastest in Musk’s experience.
The tension between rapid, paid growth and the compute required to deliver it is now on the record.
News
Tesla owners who tap Emergency Drive Away for fun are in for a surprise
Tapping Activate on Tesla’s Emergency Drive Away reportedly triggers a $539 service bill without moving.
Tesla owners who press Activate on Emergency Drive Away may be on the hook for a service bill even if their car never leaves the Supercharger stall.
Yaro, who posts about Tesla service cases on X as @Tutrifour, said a customer called after tapping Activate while still plugged into a Supercharger. The owner was about to pull away, remembered the cable was still connected and stopped. The car never moved, but the touchscreen showed a red alert reading “Emergency Drive Away has been activated” with “Service is required” underneath. A Service Mode screenshot showed the active alert BMS_a228_EmergencyDriveAwayServiceRequired, which Yaro said only Tesla Service can clear.
Here is a lesson to Tesla owners. Don’t press Activate on the new Emergency Drive Away feature on your Tesla because service charges $539 to inspect the charge port and to clear the alert. Yes, even if you didn’t move the car an inch. https://t.co/NZJENw4SQv
— Yaro (@Tutrifour) October 30, 2026
The cost of clearing it was the bigger surprise. “Don’t press Activate on the new Emergency Drive Away feature on your Tesla because service charges $539 to inspect the charge port and to clear the alert. Yes, even if you didn’t move the car an inch,” Yaro wrote. The $539 figure comes from that single case, and Tesla has not published a set price for the inspection or commented on the post. Yaro also noted that the car would still charge with the alert on screen.
Tesla launched Emergency Drive Away on October 1 with software update 2026.38.3, letting drivers pull away from a U.S. Supercharger with the cable still attached, as Teslarati reported. To use it, a driver shifts into Drive while connected, holds the brake and taps Activate. The prompt warns that driving with the cable connected will damage the vehicle and the Supercharger, and that short camera recordings will be shared with Tesla.
Tesla Charging has been clear about what follows a real activation. Repairs to a Supercharger stall can run up to $25,000 depending on the site, a service visit for the car’s charge port is mandatory, and deliberate misuse “will invoke additional penalties.” What the company had not spelled out is that the service requirement is triggered the moment Activate is pressed, not the moment the cable breaks away.
From an engineering standpoint, that is the cautious choice. Once Activate is pressed, the car cannot be sure the charge port latch was not stressed, so flagging it for inspection removes the guesswork. It also means the button carries a price on its own, which is a stronger deterrent against casual use than any warning screen.
Customer called because they have an active alert after tapping ACTIVATE on the new Emergency Drive Away feature. They didn’t actually drive away but were about to until they “remembered” they had the charge cable connected.
This alert can only be cleared by Tesla Service. https://t.co/SkHyJJPFwU
— Yaro (@Tutrifour) October 28, 2026
The report follows the feature’s first known real world use, when a driver in Austin during F1 weekend appeared to trigger it by accident and dragged the Supercharger cable along with the car. The Reddit user who filmed it said the driver seemed to have only half read the prompts.
For owners, the takeaway is to treat the red prompt as a stop sign. If it appears after shifting out of Park by mistake, shift back and unplug the normal way from the touchscreen, the Tesla app or the button on the charge handle. Activate is meant for moments when staying at the stall is the bigger risk, and Tesla is now pricing it that way.
Elon Musk
Elon Musk calls Earth’s data centers “peanuts” next to what SpaceX is planning in orbit
Elon Musk says SpaceX capex efficiency is underestimated as orbital data centers loom by 2028.
Elon Musk is pushing back on one of the biggest worries hanging over SpaceX stock. In a reply on X on Sunday, Musk said the company’s capital expenditure efficiency is severely underestimated. He was responding to a Milk Road Stocks post citing analyst Kyle Reidhead, who estimates SpaceX will need to spend roughly $470 billion over the next five quarters.
Reidhead built that figure around the target SpaceX set on its third quarter earnings call: 13 gigawatts or more of compute by the end of 2027. In his breakdown, Nvidia captures 83 to 89 percent of the spending. SpaceX ended the quarter with 1.7 GW of nameplate compute and guided to $35 billion to $40 billion in fourth quarter capex, as Teslarati reported.
Musk did not attach a number to his claim, but the earnings call shows the argument. CFO Bret Johnsen said new compute currently pays for itself in under a year at today’s pricing, and Musk said that window could shrink to six months next year. Using that pace, Reidhead argues about $230 billion of the $470 billion could come from operating cash flow and about $60 billion from SpaceX’s roughly $90 billion cash pile, leaving around $180 billion to borrow. Musk confirmed last week that SpaceX had already closed a new $40 billion debt raise to buy GPUs.
The ground buildout is not the end goal. It is what is meant to pay for the move to orbit. Replying on Friday to charts built from Sequoia partner Shaun Maguire’s SpaceX model, Musk wrote that “Terrestrial compute will be peanuts compared to orbital compute,” adding that orbital compute deployed per month “probably exceeds terrestrial around the end of 2028 and then far exceeds it in 2029.”
Maguire’s model shows how steep that path is. It has capex climbing from $88 billion this year to $290 billion in 2027 and $369 billion in 2028, with SpaceX burning $77.8 billion in cash this year and $122.6 billion next year before turning $114.9 billion cash positive in 2028. Musk’s response to the model was, “I think we can do better.”
The orbital half runs through Starmind. SpaceX plans to operate up to 1 million AI satellites flying in clusters of about 10, linked by roughly 10 terabits of bandwidth, with deployment of thousands of units starting as soon as late 2027 out of its Gigasat factory in Bastrop, Texas, according to SpaceX’s space safety page. Musk has said each Starmind spacecraft will carry more than 250 kW of solar power.
Getting there depends on launch volume. Maguire’s model assumes 250 Starship flights in 2028, up from two this year and 38 next year. The nearer test is financial: SpaceX guided to $33 billion to $37 billion in first quarter 2027 revenue, more than double the $14.58 billion it booked in Q3, and Musk reposted that guidance again on Sunday morning.