Morphing Handcycle Reference Design V1 Released

 

 
Morphing Handcycle Reference Design - Low Rider, Side View
 

 

 
Morphing Handcycle Reference Design - High Rider, Side View

Move With Freedom has been working on the design of a practical Morphing Handcycle for a few years. We are now at an important juncture where we switch from the design process to that of helping the product get into production.
 
Move With Freedom makes open source designs. The design process can be traced right to its beginnings by looking at the posts in this blog: http://morphhc.posterous.com.  You can see a movie of the Morph in action here.
 
Our designs are free and open to anyone who wants to use them. At the same time, we want to encourage manufacturers to add value to our designs and put them into production.
 
So, today we are announcing two important developments:
 
1. Availability of the Morphing Handcycle Reference Design V1 (PDF)
 
2. Move With Freedom, Inc. has placed an order with Intrepid Cycles for four production Morphing Handcycles, 
 
If you would like to design your own production versions of the Morph, we are ready to help. Just ask for what you need.
 
What follows are some illustrations from the document:
 

 

 
Morphing Handcycle Reference Design - Schematic of Key Components
 

 

 
Key dimensions are provided for all schematic parts.
 

 

 
Automatic Seat Tilt Linkage is explained.
 

 

 
Calculations for the Adjustable Lift System are provided.
 

 

 
A detailed design for the morphing pivots is proposed.
 

 

 
Dimensioned drawings are provided for all key parts. (This is a partial view)

Here is the Morphing Handcycle Reference Design V1 (PDF)
Note that you can download this document by clicking the link at the end of the post.

 

A Detailed Video Review of the Morph 4 Wood Model Before It Goes to Metal

This is a detailed video review of the Morph 4 wood model. It shows each joint in detail, and gives an overview of the mid-morph lock that I'm proposing. This video is intended as input to Graham Butler, who is starting on the frame design for Morph 4. The wood model shows the location of all the joints, and demonstrates how it all moves. The actual frame design will keep this same geometry. Of course, all the rest of the decisions still need to be figured out -- the mechanics of the lift system, the foot rests, the seat adjust, the mid-morph lock, and the frame design and materials. Over to you, Graham. We have another online design session on Wednesday, January 20, 2010.

Morphing Handcycle: Morph 4 e-Drawings Model - View the Reference Model in 3D

Side view of reference model for Morph 4.

Rory, Graham, Alan, and Bill are planning an online design session for Wednesday, Jan 13. These e-Drawings models along with the earlier drawings showing dimensions will be useful for the discussion.

Our man's name is "Slim Flatstock"

He disappears in front view.

Isometric view.

Here is the e-Drawings file for the SolidWorks model:  You'll need the free e-Drawings Viewer (for Mac or PC)

Comparison Drawings: Morph4 vs Morph 2 Do the Numbers Match Up? Yes.

Before we go into detailed design for the actual Morph 4 prototype, I asked Alan to check the key dimensions of Morph 4 against those for Morph 2. Everything looks good in the drawing above.

Trail in Low Rider: 2.5" (okay, a bit more trail than Morph 2's 1.3")
Trail in High Rider: -1.3" (same as Morph 2)

Wheelbase High Rider: 42.46 inches (1/2" more than Morph 2)
Wheelbase Low Rider: 59.37 inches (3/4" more than Morph 2)

Height to seat joint, low rider: 9.83 inches vs 12.03 Morph 2
Height to seat joint, high rider: 23.67 inches (.4 inches higher than Morph 2)
Seat height delta: 13.84 inches (2.63 more than Morph 2...very important for low CG in low rider)
Eye height delta: 16.21 inches (extra is due to change in seat back tilt?)

These are the measurements for Morph 2. Note that Morph 2 doesn't have the automatic seat adjustment system, and that it doesn't come down as far.

All of these dimensions and angles look good. Nice drawings, Alan. Very clear and simple.

CAD files of M4n - wood model

[From Alan Ball - January 12, 2010]

Attached to this email message is a pack 'n go of the solidworks model. Please note that I built this in SW 2009, so you may not be able to open it. With this in Mind I am sending you some edrawings, and also a step file and an IGES file( in the zip file). I hope this is sufficient for you to see what we have been up to.

PDF: Morph 4 Dimensions Compared to Morph 2

[From Alan Ball: January 12, 2010]

A while ago you requested some orthographic views with key dimensions called out for the M4. Check out the drawing I have attached here. Is this what you had in mind?

For comparison , I have included a drawing of the M2 geometry, which I documented in CAD and was measured and confirmed against M2. As you can see, the basic dimensions are almost the same, with differences occurring due to M4 greater range of morphing motion.

Online Meeting: Graham Butler Rejoins Morphing Handcycle Team - We Move Towards Manufacturing

Graham Butler with the very earliest roadable version of Morph 2 - April, 2007. The seat is a piece of plywood, and and the seat back is just the frame. We are on the streets of Dorchester, MA, behind the Nexus Machine and Gallery machine shop where Graham constructed Morph 2. Note the big adjustment struts near his hand. These were intended to adjust the angle of the seat after morphing. They have been replaced by automatic linkages within the morphing design.

We took a very important step today towards getting the Morph into production. We discussed our future in an online meeting conducted with Rory McCarthy (Bath, Maine) the inventor of the Morph , Bill Warner, co-founder of Move With Freedom, and project manager (Cambridge, MA), Alan Ball, industrial designer (Somerville, MA) and Graham Butler, mechanical engineer and founder of www.intrepidequipment.com and the engineering lead on Morph 2. (By the way, we used www.yuuguu.com for the online screen sharing, and it worked very nicely, and allows up to 5 users for free.)

For about a year now, we have been working to refine the design we now call Morph 4, and solve key issues such as morphing geometry, steering geometry, and seat adjustment and seat tilt correction during morphing. With the latest design for Morph 4 delivered by Alan Ball on Christmas Day, complete with 1/4 scale wooden model see: http://morphhc.posterous.com/a-christmas-morph-alan-ball-delivers-a-scale, we now have a design that is ready to move forward to production.

Graham Butler was our original mechanical engineer on the project, and designed the Morph 2 and Morph 3 prototypes. (We then took the lightweight front end of Morph 3 and mated it with the smooth-morphing rear end of Morph 2, and created Morph 2.5, which is what Rory is riding now.)

Now Graham will be taking the mechanical engineering lead again to bring Morph 4 forward into a production vehicle. Graham’s company is currently building handcycles, so this production knowledge will applied to the design of Morph 4. Welcome Graham!

Key Items to Work Out For the Production Morph 4.

1. The Footrest - We need to design a great footrest that handles the wide range of issues that the Morph presents. First, now that the seat automatically adjusts as you morph up and down, your seat bottom will be tilting at different angles relative to the footrests. This means that that your feet will move up and down in the footrest. We’ll need some kind of movable element to give you support at the bottom of your foot. And the under-the-leg supports will also have to allow sliding of the leg up and down.

2. Adjustable Lift System - A gas shock (shown in green) provides the lift that makes the rider “weightless.” There is no motor for morphing. You just grab the wheels, and because the gas shock is compensating for your weight, you can pull yourself up with no effort.

But the lift system has to balanced to each rider. One way to do this is to order each gas shock at a custom force. But this means that the others cannot try the Morph, or if they do, they won’t have that wonderful weightless feeling. Too heavy, and they will morph down quickly and have a hard time getting up. Too light and they won’t be able to morph down and will pop up.

So, we desire an adjustable lift system. Ideally, one could adjust the lift in seconds, either to suit their riding tastes, or for a new rider. We don't believe you can adjust the gas spring itself. However, you could remove and reinstall the gas spring in a slightly different location so it has a different mechanical advantage. And, this could be combined with some mechanical springs that could be tensioned more or less to adjust the lift.

We believe that the spread of the morphing concept depends on people trying the machine, and that can only happen if the lift system is easily adjustable.

3 - Mid Morphing Lock - Currently, the Morph locks in the low position, and in the high position. (These latches, by the way, have been problematic as far as reliability.) For Morph 4, we believe that some mid-morph locking positions are important. For example, you’d like to lock the the morph at a convenient height for wheelchair transfer. You’d also like to lock it at a good “upright handcycle” height for riding around town, rather than at the fastest road speeds which would occur in the low rider mode.

Designing the mid-morph lock is tricky, because the morph moves over such a wide range. Here I show a mid-morph lock concept (in yellow), that will lock in a few positions, and then stows below the black morphing arm. The rider rotates it up to use it.

A Christmas Morph! Alan Ball Delivers a Scale Model of Morph 4 on Christmas Day. It's beautiful, sexy, and sleek.

On Chrismas Day, Alan Ball brought over a wonderful present - a working, 1/4 scale model of the Morph 4 prototype. Jake, our dog, is check Alan out. The wonder of this design is in how simple it looks, but how much it does. I believe we are now ready to design in metal, and build five or six prototypes so people can really experience what its like to ride a morph. What it's like to "get back the Z", meaning that you can go up and down, and not just ride around at 18-21" off the ground in a wheelchair. The Morph goes from bar-stool height in the high mode to a low and fast 13" off the ground for speed in low rider. Both modes are a thrill, but you just can't explain to people what it's like to be riding at bar stool height. You see everything in a new way compared to a wheelchair. So we need to make some prototypes and let people try it for themselves. More details about Move With Freedom, our non-profit, is at www.movewithfreedom.org.

Our previous iteration of the Morphing Handcycle wood model was much more complex in look and form, although all the joints are actually in the same place. The goal of bringing the Morph back to its "planar" and more "bike like" form has been achieve in the new red and black model. Nicely done, Alan.


Watch as Alan move the morph and his daughter does a little narration.

Our previous design sought to move the rider load closer to the rear wheels, so the frame members moved to the outside. Nice idea, but the bike ended up with a wheelchair look, and it felt more complex. It also lost that "I've gotta have that" look and feel. So we want back to the drawing boards. (Well, Alan did.)

Ah, what a difference a day makes. Okay, many days. But now we have that beautiful look again, and the Morph has all the features and range that we're seeking.

Cool wheels, huh? That's plexiglass with a notch machined on the outer edge to hold O-rings. Hey, I get credit for that one.

Again, for contrast.

The magic of the blue joints. These are the magic links that make the seat bottom and the seat back adjust their angle as you morph up and down.

Note how far above the red main tube the back of the seat bottom is.

Now look at the red main tube. It rises almost to the bottom of the seat. But it doesn't tilt directly with the red main tube, which is how things used to work.


In this very brief, video, you can see how the joints work. The seat bottom is mainly tied to the red tube on the front of the seat, and to the lower (black) link arm for the rear of the seat.

Almost Ready to Cut Wood: A Narrow-Frame Design for the Morphing Handcycle: SolidWorks for a Working Scale Model

We are heading towards a "Reference Design" for Morph 4, which we hope will the the configuration that we build six prototypes. This SolidWorks model shows a colored model of a wood model that we will use to finalize the design. The finished bike will not be made of flat sections like this!

This model is deceptive, because it looks so simple. But in fact, it encapsulates almost a year of work to figure out how to get everything we want in the Morph to all be possible in a single design: 

- A good, very low rider height in the Low Rider Position
- A full High Rider position
- Self-adjusting seat bottom so you don't tilt too far forward when you morph up.
- Self-adjusting seat back to you are comfortable in both positions. (looks a little vertical in the high mode here, but its adjustable.
- Narrow, bike-like frame
- Single gas spring (not shown). It will be mounted between the arms. This will be nice and strong.
- Slug seat bottom and seat back. (Not shown, but the room is there to do it.)
- Capability for main tube to have a coupler so you can break the bike apart for travel by car, plane, etc.
- Light weight
- Simplified construction
- Proper steering trail in high and low modes (not easy to get right!)
- Easy to build. (ie simple parts, no fancy construction needed.) (after all, this one will be made out of wood as a scale model)

High mode. Back is a bit vertical, but we can adjust based on length of the green and yellow arms.

Low mode. Note that the dowels are not shown. These will hold the wood model together and let it morph.

High mode.Notice that the seat is tilted more towards the blue tube now. This corrects the tilt that occurs when you morph up.

High Mode Isometric for wood model.

High mode iso. Remember, this is a wood model. Next step is to decide on materials, and on other items, like foot rests, locking mechanisms.

Here is the list of what remains to be figured out after this reference model and wood model:

1. Main tube materials selection - chrome molly steel most likely for main tube. (Coupler not possible in aluminum.)
2. Other members materials - probably many will be aluminum.
3. Design for the morphing joints - how to make it light, strong, reliable, easy to build, easy to repair.
4. Slung seat bottom.
5. Seat bottom adjust mechanism - we show the mechanics, but not the design itself.
6. Slung seat back
7. Seat back adjust mechanism - again, we have the mechanics, not the design.
8. Bike component selections
9. Foot rest design (this always gets too little attention!)
10. How to lock in high and low mode. (and with high reliability! Our current latch design has had its reliability issues.)
11. Desired: a way to lock the bike in intermediate positions and even ride in that mode. (Harder than it sounds!)

And then some things that may seem like minor add-ons, but they matter:

12. How to hold crutches, and make it fast and easy to get them on and off. 
13. Storage space - how do you carry groceries, for example?
14. Water bottles

Additional design issues:

15. How to make it easy to get on and off. This relates to how often people will use it.
16. Design care to be sure the high mode stays short and turning radius is good.
17. Design of pedals so rider can (ideally) turn 90 degrees in high mode)
18. Design of foot rests so rider can turn as sharply as possible in low mode. (ie avoid footrests hitting ground, or maybe they have movement)

Input to Alan for finalizing the wood model:

1. Look at verticality of seat back in high mode. Seems too vertical. Fix before we cut wood!
2. Make the steering work. (Right now its fixed.) Key design issues relate to turning at the steerer tube.

Otherwise, look good to go to wood. The nice thing is that it's very inexpensive to make a wooden model with the technique you've worked out.

Here is the e-Drawings file for the SolidWorks model:  You'll need the free e-Drawings Viewer (for Mac or PC)
(Note: this model is a little tricky because it is set to a small scale. But if you're careful you can get the views that I showed.)