Crocodile Walker Brake System Adaptation

Crocodile Walkers are assistive mobility walkers for children, the walker is positioned behind the child and aids in stability when walking. This model of crocodile walker has a brake system accessory that stops the wheels when the brakes are pressed. The problem we had with this system is there is no way to rest unless the brakes are pressed and that can be difficult for long periods of time. Our solution was to make the walker unable to roll backwards unless the brake lever is pulled.

This modification does not stop the wheels when they are moving forward.

The original crocodile walker brake set assembly is attached below. (These walkers usually have a default system to stop when rolling backwards but this original brake design doesn't have the same default, the walker can only stop when the brakes are activated which, again, was our problem)

For each individual brake modification you will need:

• Two 6-32 fine thread bolts (4 in total)

• One 6mm x 1.0 bolt (2 in total)

• Sturdy thin cable (this design uses fishing line)

Remove the anti-reverse stoppers and release pin from each walker leg. To remove the stopper simply unscrew the bolt attaching the stopper to the walker leg. To detach the release pin you will need to completely unscrew the cable adjuster bolt from the release pin and push the bolt through the pin. Then push the release pin through the walker leg attachment until the lock washer is reachable. Use a small flat head or pick to remove the lock washer from the release pin.(refer to images above)

Flip the anti-reverse stops 180 degrees from their original orientation and secure them back on to the walker legs.

The release pins will be secured on the next steps.

Print the models(This design used PETG filament), 100% infill is recommended for max durability.

Slide the adapter model onto the extension as shown in the image above. Make sure it's aligned and apply steady force while sliding it on.

Once the adapter is on, secure it with the 6mm bolt(try not to bolt it too tightly to keep the inner cylinder from cracking), then over that opening secure the cap using the two 6-32 bolts.

STL and SLD Solid Works Models for the left and right wheels are attached below

Attach the brake cable to the adapter with the same technique used to remove it, by unscrewing the bolt all the way and pushing the release pin through to reach the lock washer attachment site.(refer to image above)

Use pliers to secure the lock washer on to the release pin and fully screw in the bolt.

Using fishing line or another thin sturdy string, tie a knot around the brake cable at the base of the spring.

Orient the cable so that the spring it facing backwards, as shown in the picture above, then tie the other end of the string the top of the anti-reverse stop. It is critical that the length of the string allows the stop to rest lightly on the wheel(this keeps the walker from rolling backwards when the brake lever isn't pulled).