One of the biggest challenges in tech is figuring out what to build, so it’s exciting that there is a new opportunity with great promise (and one that is being named here for the first time): Powered Ambient Assist Devices or PAADs. A PAAD is a type of product that augments and enhances your actions (like riding a bicycle), allowing you to do what you’d normally do but with far greater ease and duration. When a consumer pedals a PAAD bicycle, they expect to move forward 10 yards, but instead they’re propelled forward 30 yards. It’s an incredible feeling: empowering and liberating, like being Superman or Tony Stark from Iron Man.
A good way to understand PAADs is to consider the user experience (UX) of a person riding a regular bicycle, a throttle-assist bicycle, and a pedal-assist bicycle. Riding any of these bicycles elicits two main feelings in the rider: effort and enjoyment. Effort is the level of physical exertion, how intensely the person is expending energy. Enjoyment is how much fun the experience is. Enjoyment is harder to measure, but typically bicycles are most fun when the rider is zipping along and expending a moderate amount of effort. This makes riding a regular bicycle a great experience on short, flat stretches, but a regular bicycle becomes tiring and tedious when climbing hills or traversing long distances. A throttle-assist bicycle minimizes the effort, but also minimizes enjoyment because it’s not engaging. The rider just pushes a button to activate a motor; if they wanted that experience, then they’d just ride a motorcycle. A pedal-assist bicycle maximizes enjoyment while moderating effort — it’s a PAAD. Let’s dig into the UX for these three bicycles.
In the regular bicycle diagram, you can see a rider commuting home from work: They start at their office in the low-lying downtown area, then they climb up a hill, and eventually reach their house. Typically, riding a bicycle expends about 100 watts of power. The diagram shows the terrain, effort, and experience graphically. While the rider is in the flat area, the ride is fun and effort is moderate. When the rider begins to climb the hill, they exert intense effort — 200 watts; the experience goes from fun to tiring.
To reduce effort and fatigue, the rider can use a throttle-assist bicycle. These bicycles are essentially a button-and-motor system that consists of a battery pack, electric motor, and a throttle button on the handle bars. This reduces the rider’s effort to just pushing a button, which requires less than 10 milliwatts of power. This reduces the effort to climb the hill, but also degrades the experience. Pressing a button is too easy, which makes the experience boring, at least for a bicycle. If the rider really wanted a button-and-motor system, they’d have purchased a motorcycle because it provides a great version of the button-and-motor experience.
The beauty of a PAAD pedal-assist bicycle is that the rider uses the pedals to both exert effort and interface with the controls for the motor. The pedals integrate with a torque sensor that measures how much power the rider generates while a speedometer measures how fast the bike is moving. The controls use speed and pedal power as inputs to control the output power of the electric motor and assist the rider’s effort. When the rider travels through downtown, the rider contributes 100 watts of power and the pedal-assist bicycle adds another 100 watts of zip to the ride. But when the rider hits the hill, the bike slows down despite the rider exerting a lot of power (200 watts). That’s when the controls kick in for the motor with 400 watts to give a substantial boost that makes the hill feel as if it were flat. The rider’s output drops to a more comfortable 150 watts. This is the essence of the “Don’t do it for me, do it with me” experience that makes the PAAD bike so special. In a PAAD, the motor assists the rider’s effort, it doesn’t replace it.
The key to creating a PAAD is having the control system seamlessly balance the contributions from the accelerators against the decelerators, which include friction and gravity. The bicycle’s speed depends on the difference between the decelerators and the accelerators — the power coming from the pedals and motor. In a pedal-assist bicycle, the control system keeps the pedal power in a comfortable range (under 150 watts) for the rider by varying the motor’s output (up to 400 watts).
The value of PAADs is in the user interface (UI). In our bike examples, the throttle-assist UI is complicated and clunky. It’s like having a hybrid car with two accelerator pedals: one for gas and one for electricity. Similarly, the throttle-assist bicycle has two accelerators: one for the motor and one for the rider’s feet. It’s annoying for a rider to manage two accelerators, especially while they’re focused on navigating a difficult urban landscape. By contrast, a PAAD pedal-assist bicycle has a seamless UI that allows the user to control the speed in the same way that they always have: with the pedals. The user never has to change their behavior. At first the PAAD feels like a superpower and then most users quickly forget that it’s even there. Of course, both throttle-assist and pedal-assist bicycles require the rider to charge the battery pack before riding, which is an added complication compared to a regular bicycle.
We’re telling you this story through the experience of a bicycle because it’s something most people can relate to, but the lessons apply much more broadly than just to bicycles. For instance, ROAM Robotics is creating one of the world’s first commercially available PAAD exoskeletons in order to enable anyone to do work more easily. Today a factory worker carries heavy boxes and goes home sore or even gets injured. ROAM envisions a future where that factory worker wears a PAAD exoskeleton and feels good at the end of the day. Today many workers stay at home because of chronic knee injuries; ROAM envisions a future where people can stay active and independent later in their life. The PAAD exoskeleton is intended to assist in labor-intensive tasks so that the entire world just feels lighter.
Recent advances in technology have made it easier than ever for folks in tech to build pedal-assist bicycles, exoskeletons, and other PAADs. One of the most important changes is that electric batteries are now cheaper and more powerful than ever. Another trend is the proliferation of Internet-of-Things (IoT) devices that connect products to the internet so that data can benefit consumers and manufacturers. Consumers enjoy software updates that increase consumer control and device functionality. A manufacturer can look at a device’s data to better understand usage and develop relevant features. Telecommunications companies including Orange see the value of providing network connectivity that is a crucial element to enable the internet of things.
PAADs make activities more accessible because they replace an experience that’s sometimes tiring or boring with an enhanced experience that’s always fun. PAADs embody the ethos of “Don’t do it for me, do it with me.” At first the consumer feels super and then they almost take the PAAD for granted because they forget about its ambient assistance. For tech teams creating new products, building a PAAD is easier said than done, but it can also be worthwhile to truly delight consumers. The world is ripe for more Powered Ambient Assist Devices. Here’s to taking advantage of an exciting opportunity.
Aaron Peck and Mike Vladimer have ridden pedal-assist bicycles including the Copenhagen Wheel and the Faraday Bicycle, but aren’t affiliated with either company. Mike measured the bicycle power output using the Copenhagen Wheel. Ludo Bernard contributed the diagrams.