17-05-2012, 02:56 PM
Stair climbing robotic device
[attachment=22261]
Economic benefits
There would be clear economic benefits for the maintainers of public buildings adopting this device. The cost of
buying and operating a small number of the robots would be considerably lower than that of constructing a
proper lift: if this robot went into production it could be sold for under £2000. Because the robot can adapt
automatically to different sizes of steps, there would be little delay between deciding to buy the device and
starting to use it. As the demand for a stair-climbing service grows, more robots could be bought.
Feasibility
Previous attempts at designing stair-climbing robots have not enjoyed wide success because they are too
complex, bulky and expensive. A wheelchair with an in-built stair-climbing capability uses this feature for only a
small fraction of its service time, and so does not represent especially good value for money. This design would
be feasible to manufacture because it was made with simplicity in mind; it would be easy to sell because it
would be independent of any particular wheelchair.
Development of the prototype
The prototype produced is intended to prove that the design works, and will be used on real staircases, but will
not carry a wheelchair. The design was begun as an A.Level Design Technology project at Bristol Grammar
School, and has received assistance from Stannah Stairlifts Ltd. The aluminium alloy framework was fabricated
with help from the Robotics Laboratory of the University of the West of England, and Barton Fabrications Ltd,
Bristol.
The robot is moved by a set of stepping motors that rotate stainless steel leadscrews. These leadscrews run
through “captive” nuts that are fixed to the framework. To optimize the “power density” of this system,
sophisticated motor driving circuits are used that draw the best out of the motors. The whole robot is powered
by a pair of 12 volt sealed lead acid batteries, of the sort that are already used safely in many stairlifts.
The electronic control of the robot is centred around a pair of interacting PIC microcontrollers: one manages the
power supplied to the motors, ensuring that the user can stop the robot in an emergency without the device
collapsing dangerously. The other microcontroller is home to the algorithm that coordinates the motion of the
robot to make it climb the stairs. These controllers are supplied with constant information about the robot’s
surroundings by collision switches and ultrasonic proximity sensors.
Other applications
The basis of my design could be applied to many other stair-climbing tasks. For example, the first priority when
a building is on fire is to remove unconscious people inside. Normally, this is done by fire-fighters, but this is a
dangerous job: a job that could be performed by a robot, if that robot could climb stairs.
Bomb disposal squads often use remotely controlled devices, with which they investigate suspected bombs,
and, if necessary, carry out controlled explosions. My robot could well be used in the improvement of such
devices, giving them greater mobility.
[attachment=22261]
Economic benefits
There would be clear economic benefits for the maintainers of public buildings adopting this device. The cost of
buying and operating a small number of the robots would be considerably lower than that of constructing a
proper lift: if this robot went into production it could be sold for under £2000. Because the robot can adapt
automatically to different sizes of steps, there would be little delay between deciding to buy the device and
starting to use it. As the demand for a stair-climbing service grows, more robots could be bought.
Feasibility
Previous attempts at designing stair-climbing robots have not enjoyed wide success because they are too
complex, bulky and expensive. A wheelchair with an in-built stair-climbing capability uses this feature for only a
small fraction of its service time, and so does not represent especially good value for money. This design would
be feasible to manufacture because it was made with simplicity in mind; it would be easy to sell because it
would be independent of any particular wheelchair.
Development of the prototype
The prototype produced is intended to prove that the design works, and will be used on real staircases, but will
not carry a wheelchair. The design was begun as an A.Level Design Technology project at Bristol Grammar
School, and has received assistance from Stannah Stairlifts Ltd. The aluminium alloy framework was fabricated
with help from the Robotics Laboratory of the University of the West of England, and Barton Fabrications Ltd,
Bristol.
The robot is moved by a set of stepping motors that rotate stainless steel leadscrews. These leadscrews run
through “captive” nuts that are fixed to the framework. To optimize the “power density” of this system,
sophisticated motor driving circuits are used that draw the best out of the motors. The whole robot is powered
by a pair of 12 volt sealed lead acid batteries, of the sort that are already used safely in many stairlifts.
The electronic control of the robot is centred around a pair of interacting PIC microcontrollers: one manages the
power supplied to the motors, ensuring that the user can stop the robot in an emergency without the device
collapsing dangerously. The other microcontroller is home to the algorithm that coordinates the motion of the
robot to make it climb the stairs. These controllers are supplied with constant information about the robot’s
surroundings by collision switches and ultrasonic proximity sensors.
Other applications
The basis of my design could be applied to many other stair-climbing tasks. For example, the first priority when
a building is on fire is to remove unconscious people inside. Normally, this is done by fire-fighters, but this is a
dangerous job: a job that could be performed by a robot, if that robot could climb stairs.
Bomb disposal squads often use remotely controlled devices, with which they investigate suspected bombs,
and, if necessary, carry out controlled explosions. My robot could well be used in the improvement of such
devices, giving them greater mobility.