Ultrasound Imaging with Smartphones

The image of Zar’s carotid artery appears on this small, portable smartphone connected to the probe by a USB driver.

William D. Richard, Ph.D., WUSTL (Washington University of St Louis) associate professor of computer science and engineering, and David Zar, research associate in computer science and engineering, have made commercial USB ultrasound probes compatible with Microsoft Windows mobile-based smartphones.

In order to make commercial USB ultrasound probes work with smartphones, the researchers had to optimize every aspect of probe design and operation, from power consumption and data transfer rate to image formation algorithms. As a result, it is now possible to build smartphone-compatible USB ultrasound probes for imaging the kidney, liver, bladder and eyes, endocavity probes for prostate and uterine screenings and biopsies, and vascular probes for imaging veins and arteries for starting IVs and central lines. Both medicine and global computer use will never be the same.

“Twenty-first century medicine is defined by medical imaging,” said Zar. “Yet 70 percent of the world’s population has no access to medical imaging. It’s hard to take an MRI or CT scanner to a rural community without power.”

A typical, portable ultrasound device may cost as much as $30,000. Some of these USB-based probes sell for less than $2,000 with the goal of a price tag as low as $500.

The electronics for the ultraprobe have shrunk over 25 years from cabinet-sized to a tiny circuit board one inch by three inches (left). WUSTL’s William D. Richard and Dave Zar have wedded a small, portable ultra sound imaging device with a smartphone (right).

Richard and Zar have discussed a potential collaboration with researchers at the Massachusetts Institute of Technology about integrating their probe-smartphone concept into a suite of field trials for medical applications in developing countries.

“We’re at the point of wanting to leverage what we’ve done with this technology and find as many applications as possible,” Richard said.

One such application could find its way to the military. Medics could quickly diagnose wounded soldiers with the small, portable probe and phone to detect quickly the site of shrapnel wounds in order to make the decision of transporting the soldier or treating him elsewhere on the field.

There are cellphone microscopes that could be available for less than $100.

About The Author

Add comment

E-mail is already registered on the site. Please use the Login form or enter another.

You entered an incorrect username or password

Sorry, you must be logged in to post a comment.


by Newest
by Best by Newest by Oldest

A correction - I said $80000 per passenger for Phoenix' light rail, but the 50000 passenger figure is 50000 *boardings* - roughly 25000 people taking round trips each day. So more like $160,000 per person.

They could have bought 40,000 Tesla electric sports cars and loaned them to people willing to carpool, getting 80000 riders as soon as the cars could be built, AND greatly stimulated the market for electric cars.

Anyhow - the simplest initial response to weather problems with "bike+bus" is to ignore them. Get the electric bikes out there being used, and don't worry if 10% of the time the weather is bad enough that riders have to get a ride to the bus stop or even drive to work.

Only as it starts to become a major factor in transit might we need to bother considering solutions. E.g. on bad weather days, the bus line could hire local taxi drivers to provide dial-a-ride service during rush hour. That could evolve naturally out of a dial-a-ride service for elderly/disabled riders.

I think four mile spacing should be fine - eBikes can get 20mph, and the average bike ride would be about 2 miles (6 minutes), worst case 4 miles (12 minutes).


Tom , you are right with lower cost items there is no need for more sharing with robotics other than the possibility of greater or near perfect safety (which is a significant advantage) and the perfectibility and upgradability advantages for the future.

In terms of the best and cheapest now then working out the details of electric bicycle zones which are optimized for safety and convenience would be the cheapest.

So in terms of maximizing customer convenience at the lowest cost with technology that would work now, then the provision by cities or through state/federal support of electric bikes integrated with buses is the best way.

Folding bikes (non-electric) are $120-140 at Walmart.
there are good folding bikes which can be rolled (pulled) well and where the passenger on a bus would take up only 20-50% extra space.
Weight is now about 20lbs but could be brought down with application of better materials which might not be that much more expensive with higher volume.

A bit of extra research effort would really make perfected electric bike systems.

Having good bikes at all points would be an updated version of Amsterdam.

Trikes and recumbant versions would enable even the elderly and those with mobility issues to ride them. (there are already the electric scooters for the mobility challenged).

They can have weather canopies. Pod covers would allow for streamlining.

Scooter comparison

62 mph scooter

36 volt system can go 30+ mph e-bike

48 volt systems up to 40-45 mph

There are also four wheel bikes and electric bikes with two seats like the Rhoades bike with two passenger seats like a stripped down car.


$4000 is nothing.

Here in Phoenix, 'we' are building light rail at about $80000 per (hoped for) passenger, before operating and maintenance. More efficient cities might get that down to $30000 per passenger.

I'd expect a "robo-Segway" or other transport would cost at least 2x the non-robotic, so getting even two customers a day to share them wouldn't save anything.

But as you point out, both are a lot more expensive than electric bikes, and the bikes can probably move faster too. I was just thinking that it'd be hard to get them on and off a bus quickly in any significant numbers.

But maybe I'm still over-optimizing the wrong thing. It's passenger convenience and satisfaction we want to maximize, so they'll use trannsit services.

Why not provide an average of 2 electric bikes per passenger? Maybe $1000 instead of $500 for one - ~$25 a month instead of $13.

Then everyone could ride one home at night, keep it, ride it back to the bus stop in the morning, take the bus, get on another to go to work, keep it, and ride it back to the bus in the evening. If anyone else was able to make use of the ones they leave at bus stops during the night and day, so much the better.


The other way is to have bus stops every 2 miles and keep Segways/electric trikes at the same speed.

Electric trikes would not have balance issues and can be cheaper at $200-500 each already. (Maybe $100-150 in volume.) Foldable or collapsible.

Either make the personal units cheap enough for one per person or enable easier sharing with not necessarily full robotic driving but a return to a scattered docking stations (like the roombra vacuum robots). Can go on standard driving pattern and following homing beacons.

Use part of some roads for unpiloted drive to docking stations. Like bicycle lanes.

Would only need to send to docking if one area was swamped with too many Segway/trikes for projected usage needs based on traffic patterns. Too many people have come to work or a long meeting and need to accomodate others.


You are almost completely correct, the key is to have a nested transportation system with the first shell around the individual, but the segway is a little to slow at 12 mph it could take up to 15 minutes to get to a bus stop, I think you need something that will go at least 25 mph (time to the bus stop ~7.5 minutes). I like way a segway is controlled but I don't like the current design. If they would make the wheels much bigger and added a chair you would get an electric two wheeled "wheel chair" that goes ~25 mph. The really great things about going with a low mass / low speed solution.
..... no serious injuries in an accident
..... batteries good enough today
..... its cheeper than the current system

And if you made it robotic ( or tele operated) you would never have to worry about parking your vehicle or finding it in a parking lot or getting it repaired or cleaned or paying insurance or worry about traffic violations or even traffic.

jim moore


The Segways are currently about $4000 per person, because every person would have to have a Segway (owned or rented when they arrive at the zone).

Robo-segways that drop people on and off wwould allow for more Segways to be available per person to lower costs.

===People in the system
Either +15 (second story) foot bridges or underground connections or highly controlled intersections where people are required to cross. People could also be required to carry radio-electronic tags so that the robo-cars have an easier time knowing where they are.

Walking people were not addressed because the solutions are relatively simple and low cost.


I don't think we really need robo cars - buses could work ok, if people didn't have to walk so far to bus stops, and if the buses didn't have to slow down to stop so often to let people on or off.

We just need:
- a program to encourage people to get Segways (loans, training fairs, licensing, legal on side streets, etc).
- buses that will let people roll right on, park and sit down.
- bad-weather riding cloaks, for places with lots of rain, snow and sleet. 🙂

Bus stops could be 4 miles apart - with reasonable routing, no more than 3 miles for any segway ride.

With fewer routes, more buses can cover each route - less waiting.

With fewer stops, buses attain higher average speeds - getting you places faster.

Robo-Segways are an obvious thought - either having a transit Segway come pick you up, or having your own that will go home or come get you.

But the main advantage of that is a modest reduction in total Segways, and avoiding modification of the buses. Leave that as a future optimization.


Am I missing something or is it you? What about the most important people - the people! Banning human driven cars in the zone would not remove all 'human dynamic obstacles'. The most important 'human dynamic obstacles' surely are pedestrians crossing the roads. What happens when one of your robotic cars knocks down a little old lady?? Were any of them crossing the roads during the DARPA grand challenge? Or do you think all us pedestrians should wear tags or file 'flight plans'? 😉


Why couldn't the driverless zones cover the whole city ? The buildings are not moving and when new ones are added the digital maps are changed. The Darpa challenge vehicles have driven urban courses safely. GPS routing can lay out a course from point A to B anywhere in the city. Then it is just a matter of making sure that the robotic cars can be made aware of each other and ensure that there interactions are simplified so that no unpredictability is created.

You would have master routing and overall automated traffic control.

Computerized car people movers that book in their "flight plan" live. With localized (intersection by intersection) safe and fast resolution of local routing conflicts.


Hmm... This gives me an idea. I've been thinking about people-movers and driverless electric cars for a while now but hadn't come up with a way to work it that made sense. So what if you did this:

Have these dedicated, simplified zones, sure; but they obviously can't cover the whole city. But what if you combined the idea of dedicated lanes (used for buses in a lot of cities) with these zones. You join the zones using the lanes, or even using the kind of elevated roadway envisioned for people-movers. So you have hybrid of free-ranging cars and point-to-point people-movers.

Anyone want to shoot this idea down? Otherwise, I may have to use it in the novel I'm planning.


Analysts assume that cars are used for transportation. This is wrong. The primary use of a car is entertainment and information gathering. It is not primarily a transportation device. People like to move around their neighbourhood and see who is doing what, what is being built, how the trees are doing etc. Being able to watch your community out the window is the main attractive feature of a car. People like this so much they will sacrifice the transportation features of a car gladly. For example, speeds have not increased in one hundred years for cars. A transportation planner who proposes better transportation technology that will degrade this entertainment characteristic will fail. Perhaps a network of cameras and an internet connection that simulates driving around would do the trick, but nothing will change in cars until this entertainment requirement is understood and more than met.


In terms of prohibiting cars and the political challenge of it, I will have to find out when I pitch mayors around the Bay Area. San Francisco, Berkeley, Palo Alto, Oakland, San Jose.


Clearly the preference is for all electric vehicles.

Gas vehicles would only be if the electric vehicles absolutely could not be scaled up in production.

20,000 to 100,000 vehicles per city seems very doable, so there should not be a need for gas vehicles.

There are also time savings for the user who would not have to find parking in a city. The smart system could identify and guide the inbound driver to a parking space beside a waiting robot car.


Why would you use gas powered cars even as a transition? Obviously, these cars are smart enough to plug themselves in - an even easier task than fueling with gasoline.

The largest dimension of most downtowns doesn't go much more than a few miles, and the problem with electric cars is, naturally, the batteries. Something like a 10 mile range electric car would be perfect for the application, and would simply blow the economics of a traditional engine out of the water.

The cost of the computers could take a bite into the attractiveness of this solution. Also, prohibiting other cars on the road is a significant political challenge.

If these challenges can be overcome, then this wouldn't just compete, but outright beat the economics of
- Buses
- Subways
- Personal cars
Yeah, it pretty much wins.


The system is using technology that is ready now in terms already demonstrated in small or large numbers. Increasing the speed means more research and waiting. Plus one hundred times current speeds of 40 mph is 4000 mph which is hypersonic.

Even using the Darpa systems involves scaling up of production and getting unit costs down.

Safety is addressed because everything in the robotic zone is tailored for simplicity. No non-computer controlled vehicles on roads with robots. There need be no large vehicles either. The option of mixing vehicles of any kind is not needed if safety is compromised in any way.

Everything is modularized and able to be separately upgrade. Vehicle power can be upgraded. Vehicles can be upgraded one at a time. control systems and software can be upgraded. Different zones can be separately upgraded. When better tech is ready then it can be adopted just maintain overall system compatibility.


I like this idea. It needs a lot of refinement, but I think you are touching on the essential change that we need for local and personal transportation. The big problem is safety. The improvement needed to increase safety is the removal of the human being as the direct controller of the vehicle. Human reaction times and attention spans are not sufficient for intense, fast traffic.

To make this feasible we have to use different levels. The walking humans should be on the top level, in the sun, and the riding humans should be one level down, where they can travel fast. We need a hundred to one speed increase to make people interested in this approach as opposed to our fun but slow present day cars.

I would not even refer to them as cars. I think of them as transport robots. You go down from the top level, call one up, and tell it where you want to go. It gets you across the city in one minute instead of sixty. Very useful as an ambulance, for example.

Anyway, this is getting at my idea of what an electric car is. An electric car is not a mechanical device powered by a heavy battery and steered by a slow witted animal. An electric car, in my opinion, will not have wheels.