Retrofit Wheelchair Enhancement

Synergise is a thoughtful wheelchair add-on, retro-fittable on almost any existing model, that aims to help users navigate more effectively and efficiently. Akin to having bicycle brakes, the ratchet system allows wheelchair users to negotiate angled surfaces with reduced friction and increased efficiency over endurance with reduced risks of RSI (Repetitive Strain Injury) to the user.

The two-way ratchet mechanism is based on a wheel that has teeth cut out of it and a pawl that follows as the wheel turns. It can only go in one direction with the pawl in place, lifting one pawl and placing the other pawl on the other side makes the shaft go in the other direction. Cables linked to a shifter on the handlebar would lift the pawls. Each lever has independent control allowing the user to go forward, backward and rotate on the spot.

The brake is a rope dynamometer attached to the shaft with the main cog which is a frictional brake. A metallic strip is in a grooved spool and when you pull the brake lever, the cable pulls the strip and touches the spool creating friction and slowing down the wheelchair in a controlled manner. This is a useful tool to reduce stress going across cambered surfaces and cornering as well as braking.

Designer: Patrick Hyland


  • Al says:

    Great work!

  • Al says:

    Great work!

    Just a personal thought, would it be better if the handle be vertically orientated rather than horizontal? Like that of skiing.

    1) It would be more compact for storage
    2) It would be more compact for maneuvering, and not being a possible hazard of hooking into someone or something
    3) I don’t know how to explains this, i just feel ergonomically, it’s more comfortable to operate with a vertical grip than a horizontal grip in this case.

  • Christopher says:

    I agree with Al, but go one step further, just have a hinge so that the user could lock the grips in what ever position they prefer.
    This is a great design. It adds functionality to an existing item. With a broken leg I was in a wheelchair briefly. It was awful. I soon moved to forearm crutches so that I’d be upright & on an eye level with others. This design also removes need for a user to be in a low wheel-level chair. A taller chair could be used, gears could be incorporated for greater speed or uphills. Many possibilities! Good work.

  • ajc188 says:

    Great work! I’ve been live with my disabled uncle, help him with his wheel chair for years. This kind of movement can eliminate the waist movement.
    I disagree with AI, vertical handle will not be easier than horizontal to push and pull in a relatively small diameter angle.
    I have some question:
    1. how to move the wheel chair backward?
    2. can the user move the wheels when the Synergise is mounted on?(for detail and small movement)
    3. can the horizontal handle detach or change angle if needed?

    If this design come to production I want one for my uncle!

  • hamid says:

    Great idea.
    but, what about steering control!
    Do you think is it simple or hard to control?

  • AVRUMI says:

    I’m disabled that using all the time a wheelchair.
    I am very like the idea of where can I buy
    Do you have a film you can show me the uses of the product

  • This is thoughtful indeed. With hi-tech wheelchairs costing a fortune, this wheelchair add on can be a cheaper alternative for those who want to throw away their outdated, inefficient wheelchair in exchange for a new one.

  • Sehr gutes Konzept das gerade für Tetraplegiker sehr interessant sein könnte!

  • How can I purchase this? I have searched the web for dealers without any luck. This is exactly what I want. It is a step up from the prototype that Amos Winter made for 3rd world countries. That chair is being re-designed for distribution in the US sometime in the future at a cost of at least $10,000.00. I don’t want all the fancy stuff, don’t care that the chair looks like something cool from the future. I want it to be dependable, easy to service, light enough to pick up and put in my SUV without a lift, and power. This looks like it fits the bill!! Just need to know where to buy, and how much is it. When you are transitioning into a wheelchair, or have been in one all your life, on average you won’t have $10,000.00 just sitting around. I am crossing my fingers and hoping I can buy this now!

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