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Launch HN: Trexo Robotics (YC W19) – Robotic Legs for Kids with Cerebral Palsy

132 points by manmeet ↗ HN
Hi HN community! We're Rahul and Manmeet, co-founders of Trexo Robotics (https://trexorobotics.com) At Trexo Robotics, we're building wearable robotic devices to help children with disabilities learn to walk, in many cases for the first time in their lives. Video: https://youtu.be/3LW4LJIpa2o

We are both Mechatronics undergrads from the University of Waterloo. Rahul later completed a Master's in Robotics at the University of Toronto and I've done my MBA at Rotman.

We started this a few years ago when I (Manmeet) found out that my nephew, Praneit, has Cerebral Palsy, and that he would not be able to walk. Not walking can lead to contractures, hip subluxation, and many physiological and psychological issues for kids. We wanted to change that. We decided to use our robotics background, along with help from friends and the top rehabilitation researchers in North America, and in 2016, watched my nephew take his first steps using our device. Watching Praneit walk is definitely the proudest moment of my life, and we realized that there are families all over the world that can benefit from this, so we started Trexo Robotics.

The Trexo device is available for $899 per month (via financing) or can be purchased outright for $29,900. It is an exercise and therapy tool, allowing children to get the benefits of daily walking at their homes. We decided to design it so that it attaches onto an existing walker. Currently, it only works with Rifton's Dynamic Pacer, but hopefully, we can add other walkers later on as well. Our controller allows you to modify the gait pattern to adapt to the needs of different kids and adjust the amount of force/assistance that the robot provides on each joint. We are already launched, with kids using it to walk thousands of steps daily. It has been amazing to see the interest of families. Our device is available for pre-order. Our 2019 production is already fully reserved, and we are now taking reservations for next year.

Really interested to hear the HN community's thoughts on our approach, and experiences families or others have had in this space.

23 comments

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option_greek
That's a great video. Are the users expected to regain some of the walking ability in the future by using these machines ?

Btw, what kind of motors go into these ? they look funky :)

manmeet
Thanks! We have done some case studies where we have found improvements in walking. However, the primary case is that by using this device to walk at home everyday, kids can avoid many of the complications that may arise from sitting, i.e contractures, hip subluxation and other issues.

We will be conducting clinical studies to evaluate the effectiveness of our device in helping reduce some of these complications.

avip
Could you make some comparison with ReWalk ?
rudasi
The ReWalk is a great device for adults with spinal cord injury as an example. The Trexo is specifically designed for children as a therapeutic device. Compared to adults who might have had spinal cord injury, children generally do not have upper body strength and in many cases have low bone densities. By building around a walker that many children already have and use we have eliminated the risk of falling and also have the ability to increase the weight bearing over time.
writimov
Fantastic product! Really great that you have been able to help people become empowered for themselves.

Scale: Do you need help reducing the BOM costs? You could go for economies of scale (and reuse 75% of the same BOM) and build a variant for adult rehabilitation for injured soldiers, car accident victims or others with leg injuries.

Or how about a variant that allows for anyone to use to strengthen imbalances in muscle training/development? It could be gym equipment that you get on, it takes measurements of your leg strength by putting you through its paces, then it gives you a customized workout to balance your muscles for optimum strength. These exercises for imbalance measurement aren't an exact fit to the machine but can give you an idea: https://dailyburn.com/life/fitness/muscle-imbalances-functio...

manmeet
We are still producing at low quantities, but we have a pathway to bring down BOM costs with scale. In terms of other applications, the technology that we are building can evolve for other uses over time, but its not a straight replacement. We wanted to target an immediate need that we saw in the world today.
dlphn___xyz
how did you determine the cost of 29K?
manmeet
This price is based on our current costs of producing and servicing these units at our projected quantities. It is still quite expensive for most families, unfortunately. Our goal is to engage with insurance companies to make this more affordable and accessible for the larger population, based on the early adopters that are buying and the clinical studies we are doing.
samstave
The thing that pisses me off is that there are so many startups or companies where insurance companies would benefit from providing service to product mappings much more smoothly and efficiently.

You should have to “think about wngaging with insurance companies”

There should be a fucking marketplace and a brokering system already in place that your products can be submitted to and that system gets you engaged with the insurance companies and thus your ultimate customers.

joedevon
That marketplace sounds like a startup idea.
lallysingh
Agreed with other poster. If you can show that other issues can be prevented/reduced, you've got a good case for insurers.
jayjay71
I just want to congratulate you on launching a product that I hope will have an incredibly positive impact for numerous families. I wish you the best of luck in your endeavor!
jamestimmins
This looks pretty amazing, and it's exciting to see this technology applied to an area that is likely overlooked but extremely important.

I noticed that the full purchase option only comes with a 2 year warranty. That seems a bit short, no? Given that this costs as much as a car, I'd expect a warranty similar to what you'd find on a Honda, for example.

I'm not your target audience, so take that with a few grains of salt.

manmeet
That's a good point. Perhaps we can build a similar model to a car warranty where the actuators are covered for a longer period, but other components are not. Atleast it gives people a peace of mind regarding the most expensive items.
balfirevic
Congratulations, this looks fantastic! I'm afraid I don't have anything useful to contribute from medical standpoint, but I have a couple of technical questions if you don't mind.

What kind of actuators are you using (motors/transmission/motor controller)? Are they off-the-shelf parts or developed in-house? What is approximate power/torque?

How did you approach the motion control aspect from the user-safety standpoint? I don't know if the device is powerful enough to cause injury, but if it is - how do you go about development/QA to minimize chance of harm?

Thanks!

manmeet
The base actuator is an off the shelf maxon, with our custom sensors and custom motor controller. In terms of motion control, safety was the most important piece when designing our system. There are safety checks in the mechanical, electrical and the software sub system. There is a maximum force that the controller exerts on the child, which can be lowered or increased for each child. In addition to the child resisting, we also had to account for spasticity and sudden tone while walking. The controller detects high resistance and caps off the max force it sends to the motor.
betimsl
How do you justify the price of $1k/mo? -- isn't that a bit too much?
joedevon
This doesn't sound like a labor of profit but more a labor of love. I'm sure the cost comes from production cost rather than an attempt to make an obscene profit. That's the reality when making a product of this nature especially at the early stages.
manmeet
We have made significant progress towards lowering the price of our system, considering that similar devices up until now cost $75k-$150k. But it is still quite expensive for the vast majority. Our price will continue to reduce over time, making it more accessible for both families and insurance.
moocowtruck
wow do i wish i could afford this... I adopted a child from a bulgarian orphanage 2 years ago who has CP and this seems like it would be a game changer for her.

Great work !