Cane mounting system design¶
Remote control BOM¶
- Custom pcb for buttons
- 5 buttons
- ESP 32 with 18650 battery holder
- 18650 battery
Measurements¶
PCB¶
Length: 91.59mm Width: 36.01mm Height: 1.9cm
ESP32 with battery holder¶
Length: 92mm Width: 29mm Height is not specified but should be the sum of the battery and the esp32 height. This should be 18mm + 4mm.
Base¶
The base is a component that will be placed on the cane, inside of which the remote will be placed. The remote can then be removed from the cane with an easy pull in order to be used separately. This can allow the user to have the remote without the cane and also can make it easy to recharge or swap remotes without modifying the cane.
Cane mounting¶
The base is mounted on the cane using velcro straps. It fits the remote control and holds in place until the user decides to remove it.
The velcro straps were chosen due to their low cost and versitility since they can be adjusted to fit in canes of different sizes. This is important because canes have a different radius ranging from 14mm to 16mm.
There are two holes on the bottom of each side through which the velcro straps pass to hold the remote on the cane.
The bottom of the base is curved in order to fit in on a cane with a radius of 16mm.
A rubber cover will be placed in the curve in order to prevent the base from moving around on the cane and extra supporting material can be placed to fit smaller cane sizes.
Magnet and metal on remote¶
The base has a magnet that allows the remote to be snapped on it. The remote has a metal part on the back that is attracted by the magnet.
The magnet that is used has a diameter of 14mm and is stuck on the back of the base using glue. It attracts and keeps the remote in place until the user decides to remove it.
Channel¶
The base has a channel that fits the remote so that it won’t move when it is inside. This is done ensure that the remote will be removed only if the user applies force in the opposite direction that was used to insert it.
There is an extrusion on the walls of the channel that prevents the remote from moving vertically when placed within the channel. As a result the only movement that can remove the remote is the opposite direction that was used to insert it.
Groove¶
Before the channel, the base has a groove that guides the insertion of the remote in the channel and makes the snapping easier for the user. The remote has also been adjusted to fit accordingly.
Remote¶
Addition for cord mounting¶
The client has mentioned that it would be a good addition to our product to have hole for a cord. This way the user can hand the remote around their neck with a cord and access it quicker without the need for the base cane or reaching into their pockets.
The design has been modified to have an extrusion on the front with a hole of 2mm radius. This allows a cord to be passed through from the front of the device. The addition was made at the front so that it doesn’t interfere with the mounting mechanism. Sharp edges have been removed from the extrusion and the faces have been triangulated.
The changes were made by creating an extrusion at the front of the remote model. A cylinder with 2mm radius was created. Using a boolean modifier the cylinder was subtracted from the extrusion to create the hole. Finally the bevel tool was used to round the edges.
The thickness of the weakest part the supports the hole is 3mm which should be enough to hold a resist reasonable force and definitely enough to hold our remote without breaking. The strength of the hold should be tested after printing the device.
Anti-slip mechanism for the cane base¶
The base of the remote that is placed on the cane needs to fit in place and not move around when pressure is applied to it. Many of the canes have nonstick coating to make the easier to clean, this is a problem for us because there is less friction between the cane and the base that is placed on it. This is visible in the following image and the cane even has a reflection because of the smooth surface.
As a result, we need to add an additional material to the base that will increase the friction and keep it stuck in place.
There initial idea was to use a removable rubber tape similar to the ones that are provided with bike lights. The issue was that we had a hard time finding rubber tape in a small package and most products were meant for industrial use. So to cut costs we improvised and picked a tape meant for preventing carpets from slipping. This was also good because it came with adjesive material and we didn’t have to use glue. The no slip tape is placed at the bottom of the base and it proved to be effecting in preventing the base from moving.
Cane mounting with velcro straps¶
The base needs to be mounted on canes of various radiuses and be removed easily without the use of screws or complex mechanisms that would take a lot of time for us to develop. The solution we found was to use velcro straps the are wrap around the cane and can be tighened to keep the base in place.
In addition to being easy to develop, the simplicity of the solution makes it easy for people with visual impairments to use the mounting system.
In the following image, the base is shown attached to a cane using the vecro straps. It stays in place even after being pushed thanks to the anti-slip tape on the bottom of the base and the tight hold of the velcro straps.
