Automatic Bed Mattress Deep Cleaning Machine

A portable mattress cleaner that removes dust, mites and odour in three stages. It beats and vacuums the mattress, sanitises it and adds fragrance, making deep cleaning easy without removing the mattress.

The mild steel frame and fabrication forms the base that carries every other part, so it is designed first from the load and size of the machine. The Springs store energy and return parts to position. The Wheels / castor wheels allow the machine or vehicle to move.

The force needed per unit deflection, k = F ÷ x (Hooke's law). A stiffer spring deflects less under the same load.

It is cheap, strong, easy to cut and weld and widely available. A frame of 25 mm square pipe is enough for most student models.

From the required speed and torque: linear speed = π × D × rpm ÷ 60. A larger wheel gives more speed but needs more torque.

Mild steel (MS) is used for the frame because it is strong, cheap, easy to cut and weld and available everywhere. Shafts are made of EN8 or bright mild steel for strength, and parts that do not carry load can be aluminium or acrylic to reduce weight.

A factor of safety of 2 to 3 is taken for static parts and 3 to 5 for parts under shock or fatigue loading. Allowable stress = yield strength ÷ factor of safety, and each part is checked against it.

The cost is the sum of raw material, bought-out parts, machining or fabrication and overheads. Our estimate for this model is about ₹5,600 to ₹8,200, depending on size, material and the workshop rates in your city.

Cutting and grinding of sections, arc or MIG welding of the frame, drilling for mounting holes, followed by assembly, alignment and painting.

Mainly open-loop: the controller runs the actuators for a set time or number of steps. Adding a sensor for feedback would make it closed-loop and more accurate.

Accuracy is how close a reading is to the true value. Precision is how close repeated readings are to each other. A sensor can be precise but inaccurate if it is not calibrated.