Do-it-yourself manual wheelchair drive. Wheelchair
A simple electric drive that turns an ordinary wheelchair into a self-propelled one was developed at the small enterprise "Electromobile". The device is quite simple; It can be made even in an apartment, without the use of special tools and materials. The most common and reliable wheelchair was used as the base one - the “400” model stroller produced by the Stavrovsky plant, although any other one can be upgraded in this way.
An ME272 electric motor with a voltage of 12 V and a power of 100 W (from the fan of a Zhiguli car) is recommended as a power unit. Torque from the engine shaft is transmitted to the wheel using a simple friction roller. It is fixed on the motor shaft with a pin and a special extended nut. The best material for the roller is cast iron, as it has good friction properties. It should be noted that the roller and special nut are the only turned parts of the entire structure.
The electric motor is secured with three M6 threaded rods on the intermediate plate. And that, in turn, is fixed to the frame with an M8 screw.
The friction roller is pressed against the wheel by the right parking brake mechanism, so that its handle turns into a clutch control lever. Modification of the mechanism consists of removing the plastic brake pad and cutting off the part of the lever on which it was attached. At a distance of 3...5 mm from the edge of the cut, a vertical groove measuring 4.2x6 mm is sawn into the lever, through which an M4 bolt is passed, connecting the lever and the intermediate plate - the base of the electric motor.
The former brake mechanism should be adjusted so that when you press the lever (until it locks), the roller is pressed into the tire by 5...7 mm, and when the lever is moved to the other extreme position, it comes out of contact with the wheel.
To install the clamping unit into the chair frame, it is necessary to cut off the seat fixation pipe. This will not affect the strength of the chair, but since such a procedure is usually performed infrequently, these difficulties are unlikely to be of fundamental importance.
A 6ST55 type car battery is installed behind the seat on a frame made of duralumin corners, secured to the frame with M6 screws.
Wheelchair model "400", equipped with an electric drive unit "Eletran-2" (the battery is not shown in view "B") (click to enlarge): 1 - chair model "400"; 2 engine control unit; 3-toggle switch S1 for turning on the engine; 4 - toggle switch S2 "forward - backward"; 5 - chair control lever; 6 - cable from resistor R16; 7 - clutch control handle; 8-electric motor ME272; 9 - friction roller (cast iron); 10-motor base (steel); 11-battery 6ST55; 12-frame for battery (corners 20x20 mm); 13 - drive wheel; 14 engine control handle; 15 - M6 screw with nut and locknut; 16 - special nut for fastening the friction roller
Steering (click to enlarge): 1 - steering lever; 2 - bushing; 3 - pipe 4 - handle; 5 - washer; 6 - cable from resistor R16
Schematic diagram of the electric motor control unit (click to enlarge)
The traction motor is switched using an electronic speed controller. It should be noted that transistors VT5 and VT6 are installed on heat sinks with a dissipation power of at least 20 W. Relay K1 - type 111.3747 - is used to turn on headlights on Zhiguli type cars. The regulator unit is turned on by toggle switch S1 type A3C-20, which acts as an overload protection circuit breaker. Toggle switch S2 type PT2-10 is designed to change the direction of rotation of the motor shaft and, accordingly, reverse the travel of the chair.
A powerful transistor VT6 is connected in series with the motor. The transistor is controlled by a generator assembled on transistors VT1 and VT2 through a device on DA1. The setting element is potentiometer R16, which is installed in the control handle in the steering lever. When transistor VT6 is fully open, contacts K1.1 of relay K1 are “shorted”. The angle of rotation of resistor R16 at which this occurs is determined by the resistance of resistor R8, and the lower threshold for “slightly opening” the output switch is set using resistor R7. The cross-section of the connecting wires of the “battery - regulator - control panel” circuit is at least 2 mm2.
The chair is controlled using a lever, the threaded end of which is screwed onto the axle of the right or left front swivel wheel and secured with an M6 bolt with a nut and a locknut. At the opposite end of the lever, a resistor R16 is mounted, which regulates the speed of movement.
Motor speed controller circuit board (click to enlarge)
Electric motor speed controller wiring diagram (click to enlarge)
The braking system of the electrified chair is standard, acting on the left wheel. To make it easier to use, the plastic handle is removed from the brake lever and a steel rod with a diameter of 8 mm and a length of about 300 mm is welded to it. Now, if necessary, the chair can be slowed down when moving in the motor version.
There are no special requirements for the operation of Eletran-2. It is only important to monitor the pressure in the tires, in particular the right wheel, to which the friction roller is pressed; if the pressure drops, it may slip. The front wheels should also be well inflated - this will reduce rolling resistance and improve handling.
An unusual vehicle, more like a box or locker on wheels, was noticed several times by motorists and pedestrians in Uruchye. It turned out that the strange machine is an electric wheelchair for the disabled. Its owner is 72-year-old Vladimir Antonovich Medvedsky, a former professional driver, and now a pensioner and disabled person of the first group. The man told the site about his love for driving, the illness that knocked him off his feet, his “box” on wheels and his so far unfulfilled dream that will help make all disabled people happy.
“I haven’t changed heavy equipment”
Vladimir’s passion for cars and being a driver manifested itself while he was still at school, so vocational training lessons were very useful for the boy, during which he received the profession of a car mechanic and a driver’s license with the assignment of the lowest, third class.
— I got my license in 1963, I could have immediately become a driver, but after school I got a job as a projectionist. In our Glubokoye region this was considered a “fashionable” profession. And then I realized - this is not my thing, I want to turn the wheel!
Two years later, the guy was drafted into the army, where his dream came true - for three years he drove soldiers on a bus. Things worked out well - there were no complaints from the military authorities, he had no traffic violations, so along with his demobilization, Vladimir rose to the first driver’s class.
After military service, Vladimir decided to move to the capital; his sister had just moved there.
— As usual, “through acquaintance,” I was hired as a driver in a military construction detachment—just what I needed.
Vladimir Antonovich drove soldiers all over the Soviet Union, drove various vehicles: from a bus to a dump truck, “he didn’t ride except on deer.” And once I even tried to work as a personal driver for a big boss. Volodya really wanted to ride the Volga. But the boss turned out to have a complex character, and six months later the young driver returned to big cars. So I worked for them all my life.
Vladimir Antonovich’s salary at that time was decent - about 200 rubles. He received a little more than other drivers, because he combined the work of a driver with a car mechanic.
“But don’t think that the drivers were forced to do the repairs themselves.” For this purpose, the military unit had huge workshops with excellent equipment and very good car mechanics. There were no problems with repairs. But I liked doing it.
“No registration certificate - no garage”
In the 70s, Vladimir got married, and soon the newlyweds had a son. A few years later, the family was offered a plot of land near Minsk to build their own house.
“I was happy, of course, I took it.” I decided right away that I would definitely build a garage! Although this could not be done so simply: first you had to present the registration certificate for the car and only then build a garage.
However, Vladimir Antonovich still built the garage. And soon a car appeared, “no matter what” - “Moskvich-2140 luxury”.
— Passenger cars were sometimes allocated to the military unit, but people often refused them - there was no money. And then one day they announce over the selector: who wants to buy a Moskvich car? I started up, but my pocket was empty. And the car cost eight thousand rubles!
Vladimir Antonovich threw out a cry among his friends.
— Some gave 500 rubles, others a thousand or two. And the next day I had the required amount in my hands. That's how I bought myself a car. True, my parents later helped me pay off my debts.
The motorist drove a Moskvich for twenty-five years. He says that the quality of the cars back then was “highest.” Then I replaced the car with a Volkswagen Passat, but I didn’t really drive it - illness got in the way.
“They said I won’t get up, but I’m walking”
— I only had two months left before I retired... I was busy driving a working MAZ near my house. I climbed onto the body and at some point suddenly realized that I couldn’t feel my left arm and leg—they were paralyzed. I couldn’t get down myself anymore...
At the hospital where he was taken by ambulance, they diagnosed him with a stroke: the left half of his body was paralyzed, although Vladimir Antonovich did not lose his memory or speech.
“The doctors didn’t tell me anything, but they warned my son: the prognosis is disappointing, your father may no longer walk.” I was discharged from the hospital and given indefinite group 1 disability.
During the first months, Vladimir Antonovich lay in bed, his children and grandchildren looked after him.
- I think, how long will I lie there? I began to slowly do exercises. Or I lie down, watch TV and pull an expander back and forth. And after a while the hand moved and I got out of bed. The doctors were surprised!
The man began to move around the house, and then began to go outside with a cane.
“They gave me a wheelchair, but you can’t go far with it.” The front wheels are small there: a 2.5-centimeter curb is like a high wall for me. It is not surprising that disabled people cannot go anywhere and are forced to sit within four walls!
To go to the clinic, Vladimir Antonovich was called a taxi, later a special taxi for disabled people appeared, sometimes the son took off from work and gave his father a lift in his car.
— And then the Association of Wheelchair Users offered me equipment from Germany, brought for the disabled. Of course, it’s not new, but it’s on the go and free. Of course I agreed.
“There are headlights, hazard lights and reflectors”
The foreign technology turned out to be the “Delta-2 wheelchair vehicle,” more like a three-wheeled electric scooter.
“As soon as I got it, I thought: I need to make a roof so that I can drive out in any weather.”
The man shared his thoughts with his son, but he did not approve of the idea.
— He tried to dissuade me, saying that people would laugh. And then my son agreed and everyone started helping me: my son, my grandson, my neighbor, and even the guys from work responded.
Under the leadership of Vladimir Antonovich, the “combat team” made a frame from metal pipes, which was welded to a wheelchair. It was sheathed on top with sheets of duralumin - holes were made in them for windows and plexiglass was inserted. On one side they installed a door that moves along guides. For better cross-country ability and stability, the rear wheels were made double. Something the “homemade” ones didn’t work out right away, so they had to redo it several times.
The “box” contains emergency lights, direction indicators, two headlights (one of which, halogen, was installed by the craftsmen themselves), and a sound signal. Reflectors were glued to the back and a flicker was hung.
— When the “car” was ready, I first drove it to the store, then gradually began to go into the city — to the clinic, the church. The “car” starts without a key and can drive at a speed of 16 km/h. I found out experimentally that one battery charge is enough for 30-40 km of travel. I recharge it right in the garage, plug it into a 220 socket at night, it consumes little electricity.
“This little box is my legs!”
“Now, when I drive around the city, all the pedestrians look and are surprised. Drivers overtake and film from their cars with mobile phone cameras.
Most often, Vladimir Antonovich drives his “box” along the roadway. This is because there are a lot of curbs on the sidewalk that he cannot overcome.
— This machine is my legs. But as a former driver, I understand how to drive so as not to disturb anyone: I don’t drive into the middle of the road, I drive along the edge. If a truck or bus is driving behind me, I immediately pull over to the side of the road to let them pass. If I need to turn left, then I do it through the pedestrian crossing, without jumping into the intersection. Not once did any of the drivers swear at me or make any comments.
People are interested in the unusual car, especially near clinics.
“They say that someone has a relative or acquaintance who is disabled and they ask where they can buy such a car. I advise them to look on the Internet: there are tons of similar solutions there. By the way, such vehicles have been used in Ukraine for a long time. And in Europe, even just elderly people, not disabled people, ride in such wheelchairs.
“I want disabled people to be happy”
Vladimir Antonovich is very pleased with his modified wheelchair. But he worries about those who cannot overcome curbs, steps or thresholds in their wheelchairs and are forced to spend all their time at home.
— It seems that disabled people are given domestic wheelchairs, but what’s the point of them... It’s impossible to ride on them.
The man knows how to make Belarusian wheelchairs more comfortable and passable. He reported this to the designer of the prosthetic and orthopedic rehabilitation center.
“He told us: the production of strollers has already been established, it is difficult to rebuild it. Well, they didn’t start producing Zhiguli right away with the latest model! Why not make some changes little by little?
In the coming days, Vladimir Antonovich and his neighbor Valery will go to an appointment with the general director of the enterprise regarding this issue.
— We will ask him to allow us to modernize wheelchairs. We want him to hear us and meet us halfway. All disabled people will say “thank you” and will be much happier.
This idea is dedicated to the creation of a new product on the market for disabled equipment (an amazing thing, but I have never seen such a necessary device anywhere, neither here nor in the West).
My opinion about the need to create such a product is based on logic, personal experience and an example from someone else’s life. But it is quite possible that it may turn out to be wrong. So I don’t give a 100% guarantee.
Logical rationale for the need for a gurney
When we go to an online store to buy a blouse, what kind of blouses or blouses do we see there? Long sleeve, three-quarter sleeve, short sleeve and sleeveless.
Let's come closer to nature. In the northern hemisphere, the duration of darkness varies from 7 hours (in June) to 17 hours (in December). And it changes gradually, a few minutes a day. We even have spring and autumn equinoxes.
People are 150 cm tall, and sometimes 200 cm tall. And between these two sizes, millions of cases of height 160 cm, 175 cm and so on can be recorded. That is, we don’t have only small people or only big people. There will definitely be those who will be BETWEEN on the growth chart.
That is, the law of nature says: between two extremes there must be a middle state.
How many vertebrae does a person have in the spine? 32-34 (why not exactly? Because some coccygeal vertebrae are fused). When the upper vertebrae break (with damage to the spinal cord), most often the person does not move either his arms or legs (usually he turns into a bedridden patient and only lies down). When the lower vertebrae break, usually only the lower part of the body does not work (and then the person turns into a sedentary patient - he can independently ride in a wheelchair).
What happens when a person’s middle spine is disrupted? Is he lying down or sitting? Most often he can sit, but very poorly. And he doesn’t want to lie down, because his arms and some back muscles can work (why does he need to lie down all the time?).
And for some reason, the needs of these people are largely not taken into account.
So, let's come to the most important thing.
Every person - both disabled and healthy - needs hygiene. In particular, you need to take a bath or shower (at least, that’s how it is with us, Russians).
What does our industry offer to make washing easier for people with disabilities? There are only two extreme options:
1. If a person can sit in a wheelchair, then he can sit in the bathroom. And he can also drive up to the bathroom in a wheelchair. For him, the industry produces bathroom chairs and devices for transferring from a stroller to the bathroom to this chair.
In this case, the process of transplanting into the bathroom may look like this (photo from the page santechniki.com/topic7745.html):
In my opinion, it is quite risky for a person who has no support on his legs.
2. If a person is just lying down, then he is not offered a bath. And they suggest washing right in your bed - for this, all sorts of wiping products or portable bathtubs are produced (in which you need to somehow pour and drain water; this bathing is more like the ancient washing in a basin, when there was no running water yet).
This staged picture does not show what water should be added to such a bath (and even make sure that it does not cool down). It is not clear how to rinse a person (or do the producers of the “show” think that our person is ready to be content with dried dirty foam on his skin?). And what to do with a bed that is wet after taking a bath (or do you think it’s so easy to wash a bedridden person without splashing)? And how can you wash a person’s back in such a bathroom? (In a real large bathroom, where there is a lot of water, it is easy to turn it on its side and wash all sides.)
People who are in the middle situation (who are not recumbent, but also have difficulty sitting) are not offered anything according to their profile. But they obviously won’t sit on a high chair in the bathroom - it’s easier for them to stand on all fours in the bathroom, or lie on a special slide - and it’s very difficult to unload them from a regular wheelchair into the bathroom (the railings of the wheelchair are also a hindrance, and the fact that it’s easier for a person to get off to the bathroom from a position lying on your stomach, and not from a position “sitting on your butt” - as soon as possible in a wheelchair).
Should he really refuse to take a bath just because it is difficult for him to get into it and sit on a small chair?
(For a person leading an active lifestyle, despite a disability, this is impossible! And it is stupid and inconvenient for the people around him to bring a newly invented portable bathtub to the bed, which is not ready to receive a large volume of water, rather than bring a person to a long-tested one that is connected to the water supply and sewerage to a real bathtub, which is already in every apartment)
But theoretically, there is an excellent solution to this problem - a gurney! Any disabled person can be unloaded onto it from the bed by simply turning the body around its axis (and immediately from the back to the stomach). And it’s just as easy to unload a person from a gurney into the bathroom (if his arms work, he can go down into the bathtub, leaning on it with his hands; and an assistant will help lower his legs; or you can do the opposite - first the assistant lowers the legs, then the upper one lowers into the water part of a person). All nurses know this - they do it every day in their hospitals, when they transport bedridden (and even healthy, but sick) people to procedures and operations.
Why not take sick people at home for home water treatments in the same way?
Of course, it would be possible, if not for our home narrow corridors and doorways. Have you seen hospital gurneys 70 centimeters wide? They travel along wide hospital corridors, but there is no way they can fit through the average bathroom door from the average residential hallway.
Why not make special home gurneys the width of a regular wheelchair (that is, about 40 centimeters) and shorter - not 2 meters, like hospital gurneys, but 1.2-1.5 meters?
What, a sick person will fall off her? No. To travel 4-5 meters to the bathroom, he will not do what is not necessary - fidget, spread his arms, or even jump. (You can also fall from the top side berth of a reserved seat carriage, but people travel on them for thousands of kilometers - and it’s okay, everyone is alive.)
What is taking a real bath like for a person tied to his bed? This and the feeling of lightness in the water. And water therapy. And a change of scenery. And cleanliness!
Personal experience
When my daughter was little, I carried her to the bathroom in my arms - bathing was not a problem for us.
When she grew up, her husband began to carry her to the bathroom. This has already become problematic.
First, we were now tied to his work schedule and lifestyle. We are going to go swimming on Sunday, but my husband stayed in the garage and the child was left unwashed.
Secondly, carrying a person in your arms is unsafe. The person carrying it may trip or sway and run into a wall or corner, which could result in injury.
Thirdly, when a wet person gets out of the bathtub, covering him well with a towel while carrying him in his arms will not work. The towel will definitely come off and get tangled in the “porter’s” legs, and the child may open up wet and catch a cold.
For several years I thought about what to do in such a situation. She sat the child on a gymnastics mat and dragged her to the bathroom. This in itself was very difficult. And getting from the bathroom floor into the bathroom itself turned out to be an impossible task.
Taking her to the bathroom in a wheelchair was out of the question. Getting a person out of a wheelchair into the bathroom is very dangerous in terms of various types of injuries.
And then my husband and I decided to convert a regular wheelchair into a compact wheelchair. I don’t know what my husband did to her, but he somehow removed her back and footrests and she turned into this compact wheelchair (though there were still high arms, they still get in the way, but we decided not to cut them off - my daughter climbs onto the gurney from the end of me):
You have no idea how much easier my life has become!
Now we swim at any time (if we want - early in the morning, if we want - in the evening).
Using the gurney turned out to be injury-free for my daughter and easy for me personally (there is no need to drag and lift the child; she simply transfers from her sofa to the gurney, we go to the bathroom, and in the bathroom she slides off the gurney with her back - I help her lower her legs - and just plops down into a bathtub filled to the brim with water).
And even if the homemade gurney is a little too small for her (it is at least a little short - its length is only 90 centimeters), she does not need much comfort to get to the bathroom.
An example from someone else's life
I once had a chance to hear an interview with the widow of Vladimir Migulya, a composer who was struck down by illness in the prime of his life. And who gradually turned into an invalid and could no longer walk.
He asked to go to the bathroom every day. The water not only washed away the accumulated sweat and dirt of the day, but also served as a kind of therapy.
And how do you think he got to the bathroom? His wife and daughter carried him there in their arms every day! (straining one’s health and making an adult man feel like a heavy burden)
Because even then they had not yet invented such a simple thing as a home gurney.
All you need to do is make a simple structure of four wheels and a horizontal surface for a recumbent person. It’s not for you to invent a super-passable stroller.
Simple product - great possibilities
It seems to me that there is no need to invent anything here - take a ready-made drawing and do it (just don’t forget to erase the sticky handles from the drawing - they are not needed). Then you show disabled people and their families how their lives will be made easier with the help of this basic device.
Such a simple thing should not cost much (the wheelchair that we converted into a gurney cost 4 thousand rubles, and today it costs about the same).
Production is simple. Essential product. The market is huge. All that remains is to do it and offer it.
People who have lost the ability to move independently are doomed to be confined within four walls. But they need to go to the store and want to go for a walk...
We offer a version of a homemade wheelchair, designed on the basis of a universal power walk-behind tractor - a module, which was discussed in previous publications.
Our wheelchair is an articulated machine: the chair is connected to a power walk-behind tractor using a hinge. Outwardly, it resembles the steering column of a regular moped or motorcycle, but structurally it is a steel pipe with bronze or fluoroplastic bushings pressed into it. Using two steel gussets and a connecting flange, it is connected to the mating connecting flange of the power walk-behind tractor frame.
The second part of the hinge resembles the steering bridges of the front fork of a moped. They are cut from a steel sheet 4 mm thick and welded to the front struts of the chair. The bridges are connected to the steering column using a long bolt with a diameter of 10-12 mm and a nut with a washer. Such a hinge can be assembled from parts of any old moped, using “branded” ball bearings.
The chair is connected to the axle of the stroller through front and two rear struts.
The axis of the chair is a steel pipe with a diameter of 30x2.5 mm, connected by welding to two axle shafts - stepped rollers.
Their larger diameter is equal to the internal diameter of the tubular axle, and the smaller diameter is equal to the landing diameter of the front wheel bearings. A thread is cut at the end of the shaft to secure the wheel to the axle shaft with a washer and nut.
The frame of the chair is bent and welded from steel pipes with a diameter of 25x2.5 mm. The seat and back are made of duralumin sheet 2.5 mm thick, the back and seat cushion are made of foam rubber about 50 mm thick, the covering is made of artificial leather or leatherette. At the bottom of the seat there is a welded platform for the feet. It consists of a tubular rectangular frame on which a covering made of duralumin sheet 2 - 2.5 mm thick is fixed with screws. The top of the platform is covered with corrugated rubber.
Front wheels - from any moped To fix the stationary part of the brake drum, stops are welded to their axles - steel trapezoidal plates made of 10 mm thick sheet.
The chair is controlled using a steering wheel rigidly connected to the power unit. Let us remind you that the stroller turns to the right when the steering wheel is turned to the left.
All controls are mounted on the steering wheel: on the right handle - the carburetor throttle control handle (gas handle *) and the brake handle, on the left - the clutch control handle and the gearbox shift handle.
The engine is started using a modified kickstarter: in place of the starting pedal, a pulley machined from duralumin is installed, onto which two or three turns of a nylon cord about 8 mm thick are wound. The free end of the cord is equipped with a convenient handle. It is enough to pull the starting handle and turn the throttle handle a quarter of the way, and the engine is started.
The speed of the motorized stroller is about 20 km/h. This is even a bit much for a car with such a short wheelbase that has no depreciation. Therefore, we recommend driving at this speed only on good asphalt.
Braking is carried out by two front wheels driven by one handle. To connect two brake cables to it, you will have to attach a pad and a stop to the brake lever. If you plan to use a moving chair on city streets, equip it with lighting devices: a headlight, tail lights and reflectors. It would be nice to install a sound signal from a moped on the stroller.
Engineer Z.SLAVETS
Source; Lefty 1991
1 - universal power unit with a V-50 type engine; 2 - seat back (2.5 mm thick duralumin covered with foam rubber and artificial knives); 3 - chair frame (steel pipe with a diameter of 25x2.5 mm); 4 - seat cushion (sheet duralumin 2.5 mm thick covered with foam rubber and artificial leather); 5 - control handle (on the right - the carburetor throttle control handle and the brake handle, on the left - the engine clutch control handle and the gearbox shift handle); 6 - adapter gussets (steel sheet 2.5 mm thick); 7 - steering column of the central hinge (steel pipe with a diameter of 30x2.5 mm with bronze or fluoroplastic bushings); 8 - rear strut (steel pipe with a diameter of 25x2.5 mm); 9 - front strut (steel pipe with a diameter of 25x2.5 mm); 10 - lower strut (steel pipe with a diameter of 20x2.5 mm); 11 - platform for feet (frame - from a pipe with a diameter of 20x2.5 mm, platform - from sheet duralumin 205 mm thick, covered with a corrugated rubber mat); 12 - cross member (steel pipe with a diameter of 20 x 2.5 mm); 13 - seat cushion support with a diameter of 30x2.5 mm with two steel axle shafts welded into it; 15 - steering lever (steel pipe with a diameter of 22x2.5 mm); 16 - front wheels (from mopeds such as “Riga” or “Karpaty”); 17 - brake drum stop (steel plate 10 mm thick); 18 - bridges of the central hinge (steel sheet 4 mm thick).
Electric vehicles are gaining more and more popularity every day. This became possible thanks to new good electric motors, as well as batteries that are becoming lighter, smaller, more powerful and cheaper.
Many hobbyists are trying to make various electric vehicles with their own hands. This time we will look at the method of manufacturing an electric stroller.
Tools:
- lathe;
-
-
- welding;
- wrenches, screwdrivers, etc.;
- multimeter.
Homemade manufacturing process:
Step one. Choosing an engine
The car engine used direct current with a supply voltage of 36V. This is a General Electric engine. The choice fell on this motor due to the fact that it had a suitable mount. In principle, any motor with a voltage greater than 12V can be used. A motor from an old car starter and so on is quite suitable. It is more promising, of course, to use brushless motors.
Step two. Choosing batteries
For homemade products, you can use regular lead-acid batteries, since the machine is quite large and can carry an impressive weight. You can use lithium batteries, they are more powerful, lighter, but they do not withstand deep charging and recharging well. You can also use batteries with gel inside, these will definitely not leak if something goes wrong.
The author made a frame from a corner for three batteries. And they are attached with one rubber band. The corner was found in old beds. The batteries are connected in series to obtain a voltage of 36V to power the engine.
Step three. Motor controller
To prevent the motor from immediately “consuming” the entire battery charge, or from completely burning out under load, power must be supplied to it in doses. Controllers are used for these purposes. The author installed a controller called Curtis.
When driving, the controller will heat up, so the heat must be removed from it. Make a radiator for it, an old copper or aluminum plate will do, preferably larger in size and with fins. Screw the controller to it with bolts. For better heat transfer, use thermal paste.
Step four. Reverse relay
When driving a vehicle, sooner or later there will be a need to move backwards. To do this, you will need a powerful relay that could supply a plus instead of a minus, and a minus instead of a plus to the engine. The author used devices from a golf cart. Connect and install them as seen in the photo.
Step five. Preparing the wires
You will need thick wires, preferably copper, or in extreme cases aluminum. If they do not withstand sufficient current, they will heat up, and as a result, energy will be wasted. The author found the wires from an old uninterruptible power supply. On each wire you need to make copper contacts in the form of loops. You can buy them ready-made and then install them on the wires. They are fastened by crimping; a special tool is usually used, but you can do it with help.
Step six. Assembling the frame
The frame is actually assembled from scrap metal. Old pipes are suitable, maybe round, or better yet square, a corner that can be found in beds, steel plates, and so on. Weld a structure that will confidently support the weight of passengers and also keep the wheels in place. Here you will need to think about it.
The most difficult part will be making the steering. Here you can use components from motorcycles, various carts and even from cars.
As for wheels, in principle wheels from a motorcycle or even a bicycle will do. Wheels as wide as the author's will be more difficult to find. As a result, at this step you should have a finished frame with wheels, and you can also install the seat. A car seat is quite suitable as it; it is advisable to cover it with waterproof fabric.
Step seven. Installing the engine
You can install the engine on the frame. To transfer torque from it to the wheels, the car used a chain drive from a motorcycle. We take a small sprocket and weld a bushing to it so that it can be secured to the motor shaft. Weld the second large sprocket on the axle of the rear wheels; here you will also need to make an adapter. You can get the necessary parts on a lathe.
Make sure the motor can move so that the chain can be tensioned. The movement from the engine in this model is transmitted directly to the two rear wheels by a solid axle. This is a simple solution, however, it is not economical in terms of energy consumption. When turning, the wheels will lock and require more power than if a differential were used. It is best to transfer the movement to one wheel, but this will reduce the cross-country ability of the vehicle.
Step eight. Rear axle and wheels
The author mounts the rear axle on bearings; the bearings themselves are attached to the frame using bolts and nuts.
To secure the wheels, you will need the help of a lathe or turner. You will need to machine the hubs for the wheels. Screw it tightly using bolts.
Connect the motor to the power source and make sure that the sprockets are welded straight, otherwise the chain will fly off and the motor will consume more energy.
Step nine. The final stage of assembly
Install charged batteries on the car and connect the motor through the controller. For the car you will need to make an electric pedal, usually it is connected to the controller. The author also recommends installing an emergency battery shutdown button, which can be used in an emergency. It should be in a visible, easily accessible place.
