Five Days to Go: A Look At the Morph under Construction

Today is October 23. We have five days to go before the Oct 28 unConference, and construction of the Morph is hot and heavy in San Diego.

Earlier, on September 17, I visited Graham Butler and the Morph Team to review the final design of the Morph, and to plan how the first production prototype of the Morph could be shown at the upcoming MassTLC Innovation unConference. (bit.ly/masstlc2011) Above, Graham holds the front end of the Morph. The upper part is aluminum, while the lower fork is made of steel.

Intrepid Cycles is located in San Diego. Graham also builds frames in his home country of Brazil.

A screen shot from Graham's computer. We tested different rider sizes. It looks like Bill and Rory both fit easily on the same bike. The footrests mainly take up the difference, along with the adjustable pedal post.

Seth Arseneau drove from Albuquerque to work with us. Seth is handling the rear, morphing part of the bike, even though here he's holding the front end which was made by Graham and company in San Diego. Seth is focused on some of the highly machined parts that make the Morph do its magic.

These are the "upper morphing arms." They allow for an adjustable lift system so a variety of rider weights can be accommodated with a single version of the Morph.

This is the assembled upper morphing arm. The silver parts have been machined out for weight reduction and cool looks. The tool did not cut all the way through so we maintain maximum strength in the arms. Note the metal table. This is Seth's very cool fast welding table that makes holding weldments easy.

The upper morphing arm, upside down. You can see the lead screw and the "carriage" which allows the mechanical advantage of the gas springs to be changed by turning the bolt on the end of the lead screw.

It may seem like a minor thing, but I need a crutch holder so I can stow my crutches when I ride. We used a couple of pens taped to together on the scale model to see how that might work.

As the Morph moves down, the crutches will tilt back.

When all the way down, the crutches will tilt back nicely. Maybe we should have a little flag on them for visibility.

Here Graham is checking out the Morph with a proposed storage system that hangs under the seat. (shown as a rubber band.)

Bill's idea is to have something that hangs below the seat and can hold lots of groceries, for example. Especially in high rider mode.

This is the Schlumpf Speed Drive. It gives a 2.5x increase in gearing when you hit the button in the crank center. This 2.5x is important, because we have a very small front wheel...only 18" in diameter.  This is 1.5x smaller than a 27" (700c) normal bike wheel. So, when you morph down, you'll engage the Speed Drive and you'll have plenty of gearing to get all the speed that the low, fast, highly maneuverable Low Rider mode offers.

Bill used his Travel Bike on the trip to San Diego. The front end of the Travel Bike has many similarities to the Morph. Same 18" wheel. Same 8-speed internal hub with brake (from Shimano). Also, a couple bungee cords are holding my wheelchair on the back, and that also acts as a luggage cart. Nice setup!

Morph Design is Done! Ready to Roll at Oct 28 MassTLC unConference

The Morphing Handcycle design is done, and we're building six units. This post uses a CAD model that is close, but not exact to what is being built. The first of the Morphs will be unveiled at the MassTCL unConference http://bit.ly/masstlc2011 on October 28. At the end of this post is a CAD model that you can view in 3d using Solidworks free eDrawings viewer.

The Morph in High Rider mode. This is a screenshot from an earlier design. The red tubular member on the top has been replaced by the milled aluminum part on the new design in the first picture.

(Wheels and seat back hidden) The adjustable lift system lets us handle almost any weight of rider and make them "weightless" so the Morph goes up and down in seconds with no effort. The dual gas shocks give us plenty of lifting power.

Loosen the four bolts that cinch the carriage (in light blue), and then turn lead screw (dark blue) to adjust the mechanical advantage of the gas shocks. Then re-tighten the carriage, and you're ready to ride.

The bolt with the blue dot turns the lead screw that moves the carriage to adjust the lift. We're confident it will work well and look great! (we tested the mechanism but not this specific design)

The Morph in Low Rider mode with a rider. This is the view that comes up from the CAD model below.

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

Some tricks: you can click on a part of the bike and right-mouse click, the choose Hide, and it will be hidden for easier viewing of other parts.

The hide feature is handy.

Click the blue circular arrows to rotate. Click the green arrows to move from one view to the next.

Morph Parts Taking Shape: Seth Arseneau Making the Chips Fly

Seth Arseneau in his machine shop. Seth is playing multiple roles on the Morphing Handcycle project. First, he is helping with important decisions about exactly how to build the machine. Right now, Intrepid Equipment is building enough parts for seven Morphing Handcycles of the Morph 4 design. Seth has already contributed to the design that is being cut from metal right now. Seth suggested that the main morphing joint be made from an external bottom bracket so it is strong, light, and easy to construct. That change is in the design. He also suggested that the upper morphing arms be made from a single plate of aluminum, rather than the welded tubular design we initially had. This has also been included in the design, Seth has cut the first pass of the arms on a friend's CNC mill.

Seth's experience with cycles and handcycle racing has been paying dividends on this project. You'll hear more about some new designs in a future blog post.

This is the upper morphing linkage arm. So nice to see it in metal, instead of CAD! Nice job, Seth. 

Drawing for the upper linkage arm. We are planning to remove much of the metal for lightness and look. The outline will not be a hole, though, to keep the arm rigid. We are planning to anodize the part, and then take out the material, so it will be a two-color part.

A 7000-series aluminum oval part for the lower linkage arm.

Seth likes an exact fit. Here, all the cross supports are lined up to make sure they are all identical and accurate.

Here you can see where the cross support fits in the lower linkage arm.

Historical Review of Morphing Handcycle Blog Posts (May 2005 to June 2009)/ Welcome Seth Arseneau

Seth Arseneau is a handcycle racer, a machinist, and a handcycle builder. Seth is joining with Graham Butler and Intrepid Cycles to work on the morphing handcycles. We welcome Seth to the team!

While I was putting together information for Seth to review, I figured I'd put it all in a blog post for posterity.

So here, Seth, and anyone else, is an overview of the Morphing Handcycle Project, with links to key blog posts, and a screen image from each one.

Our Website:  www.movewithfreedom.org
Need to update that 2009 on the upper right!

For posts dating from May 11, 2005 to February 28, 2008, we used the Apple Blog tool for our blog posts. 

What follows are key postings from that first archive:

First post 2005 Email from Rory

Original Morph - combination of Morphing Handcycle and Morphing Wheelchair:
This Intention document served as the design input for Morph II

Rory's original side view of the Morph that started the whole design sequence.
See the original post here. 

See the original post here. 

See the original post here. 

See the original post here. 

See the original post here. 

Bill riding the first Morph II prototype in April, 2007
See the original post here.

See the original post here.

Morph can go from low rider to high rider instantly....

...for very important reasons!
See the original post here.

Figuring out how to do seat correction was a long standing issue. The above link is a Powerpoint that explains the issues. We eventually made it all automatic (Thanks Alan Ball)
See the original post here.

The goal of Morph III was to get much lower in low rider mode -- to more closely match the Bobby Hall handcycle upon which the low rider mode is modeled. See the original post here.

Morph III high rider mode. See the original post here.

Note that the original Morph II had 5.1 inches of trail. Ouch, that was bad, and had to be fixed. .

We struggled with how to make the seat tilt work. Doing a manual adjuster wasn't even easy to do, and you would have had to fix it on each morph up/down. See the original post here

A look at the Morph III frame. Click the link above and then play the animation. See the original post here

We had major issues with Morph III regarding steering and seat tilt. We did radical surgery in the shop. Don't try this at home. It partially worked. View the original post here.

View the original post here. 

As we struggled to get the Morph to ride lower, Alan came up with the idea of having the main tube nestle between the rear frame. He called it "Twin Flanking Members." It worked, and we are using this approach in the final design.  http://morphhc.posterous.com/twin-flanking-members

View the original post here. 

This was a breakthrough from Alan Ball - a way to make the seat adjustment automatic. We're using this on the finished design. View the original post here. 

View the original post here. 

Detailed discussion about trail in high and low modes.

The Morph II did not turn well in low rider mode.

By dropping the front fork, we were able to get the steering geometry we wanted.

It had almost 8" of trail. Very bad. See the post for the whole story:

This post provides dowloadable as-built models of Morph II. These are .EASM files from Solidworks. The post also has a link to download a free viewer to see these files. View the original post here: (and download the files from here also) http://morphhc.posterous.com/solidworks-as-built-models-of-morph-ii-you-ca-0

We decided that a knee joint wasn't a good idea. But it's still interesting because this joint tracks what your knee wants to do in morphing from low to high. See the full post here: http://morphhc.posterous.com/powerpoint-animations-exploring-a-morphing-jo

Throughout the project, we struggled to make the new design match the geometries that we already knew worked. This post provides documentation of those geometries: http://morphhc.posterous.com/a-tale-of-four-handcycles-1982-to-2008-with-s

The post also includes three nice photos of Bill Warner riding his Bobby Hall bike, with his dog, Jake: http://posterous.com/getfile/files.posterous.com/morphhc/SvyXzHLkRyNI0UbQAd7b...

This post provides scale drawings for Bobby Hall, Morph II, and the "Morph Out" which became Morph 4. http://morphhc.posterous.com/bobby-hall-handcycle-compared-to-morph-2-and

After the fixes to Morph II, its geomtry seemed ideal. This presentation seeks to nail down exactly what that geomtry is. View the original post here: http://morphhc.posterous.com/just-like-your-teacher-told-you-geometry-is-i

Comparing the Morph and the Travel Bike - Side View Photos/CAD

The previous posts review the Travel Bike, because it shares many design elements with the Morph. Having just spent the weekend in Newport on the Travel Bike (as I wait for the Morph 4 to be completed!), I wondered if we could use the very cool hinged footrests from the Travel Bike. The short answer: No. The Travel Bike, as compact as it is, is way longer than the Morph in high rider mode. And your legs sit well ahead of the steerer tube, as opposed to behind the steerer tube in the Travel Bike. Too bad. The Travel Bike's footrests are light and functional. Here's some more details.

Side view of the Travel Bike.

I used Keynote's instant alpha feature to grab the CAD Man from the Morph pictures. I scaled both drawing so the front wheel was the same size.

Using the same scaling techniques to see the Morph in Low Rider next to the travel bike. Note that you sit about one full head height lower. The overall length is about the same.

Adding the Morph in high rider, we see how much shorter and higher the bike is, even compared with the (mostly grayed out) Travel bike.

It's interesting to note how much more your leg bends from low rider to high rider. This is because the seat moves up and forward, but the footrest stays in a similar place (it does rotate about the front contact point, I think.)

Like I said, no but you'll see.

The instant alpha took away some of the foot of our CAD Man.

These footrests are hinged at the top of the vertical orange line, and also where the two lines meet. Go off a big curb? The footrest just bends forward, no problem.

Red lines show center line of your shin in both bikes.

I hadn't realized that the seating position relative to the steering axis was that much different. It's a good 16" (size of the front wheel). This keeps the Morph short, which is really crucial for indoor maneuverability.

And there you have it.

How a Handcycle Can Break Apart For Travel: Photo Survey of the Travel Bike

Since the Morph will use some of the design concepts of my Travel Bike, here is a photo survey showing how the bike comes apart. It gets very small, and will fit in most trunks, and can go on small airplanes as well. The Morph will use the same coupler on the main frame, and it will have a similar fold-down seat. The Morph will put the centering spring entirely on the front, so the step of unhooking the centering spring will not be required.

Click on the small right arrow to view successive images below. This will give you a photo animation of how the Travel Bike comes apart:

Click on the small right arrow to view successive images above. This will give you a photo animation of how the Travel Bike comes apart.

Below is a photo survey showing more detail about the Travel Bike. It has a coaster brake in the hub, so the cam-based reversing brake isn't needed. The internal-gear hub has 8 speeds, which is okay for basic needs. The Morph has a full derailleur system, which will give it much more gear range.

Travel Bike photo survey.

Here's a picture of me on the Travel Bike. These photos were taken on a trip to Atlantis in the Bahamas. Thanks to Miles D. for demonstrating the disassembly of the handcycle.

Analyzing A Deceptively Simple Centering Spring for the Morph

This post will go over the centering spring design we'll be using on the Morph. This design has been used on the New England Handcycle for over 30 years with great success, and it was carried over to the Travel Bike (shown below) that was built for me by One-Off Titanium (Mike Augspurger). The Travel bike and the Morph share many design elements, including the 16" front wheel, the coupler to allow breaking the main frame into

Here is the centering spring as installed on my Travel Bike. Note the silver coupler in the main tube. Because the bike comes apart here, there two carabeners below allow the centering spring to be dismantled when the bike is taken apart.

Closeup of the centering spring. I can't say it's pretty, but it works perfectly, as the explanations below will outline. This same mechanism will be incorporated on the Morph, but on the front end, rather than under the main tube. And, we'll make it look much nicer.

This series of three photos shows how one chain becomes slack and the other stays tight when the rider starts turning the wheel.

This is a bottom view (well, the bike is flipped vertically) showing the size of the wings.

When the wheel is turned, the wings pull on one chain, thereby stretching the elastic.

As the wheel is turned, the moment starts decreasing, while the stretch on the elastic, (I call it the "gap"), increases. The lines in red on the left side show the relative sizes of the moment and the gap.

As you start to turn more sharply, moment starts to fall quickly, even though the elastic is still being stretched more. This creates exactly the characteristic you want: Good centering near center, and up to about 45 degrees, and then a reduction in centering as you turn even more. Because the handcycle can make extremely tight turns, even more than 90 degrees, its important the the centering spring not fight you when you're doing these tight maneuvers.

At 100 degrees, we see that that gap is big, but the moment has dropped to almost zero. Just perfect. You can steer as extremely as you want, but lets say you need to grab the rear wheels and push like a wheelchair -- the centering spring will make sure the wheel stays straight.

Below are the five slides in a picture viewer, so you can click through them without the explanations above.

Here is the Powerpoint in case you'd like to play with it.

The Morph will implement the same mechanism, but the wings will be fixed to the main tube, and the elastic will be on the front end.

Morph 4 Design Review - Screen Images

Bill, Seth and Graham had an extensive design review online today. The screen images are presented here. Later I will make posts that provide annotation. But for now, here's how things look. There are some little elements on the main tube that are not supposed to be there. (they were for an elastomer-based adjustable lift system that we didn't end up using.) Otherwise, things are getting very close. More later.

Some of the images show a yellow triangular upper morph arm. We decided not to use this. It creates a confusing look. Later images go back to the original design.

Morph Seat Angle - Upper to 95; Lower to 110 Discussion and CAD Models

One of the design issues we've been working is how to get the seat back in high rider mode to tilt back enough.


Date: May 3, 2011 1:50:10 PM EDT
From: Graham Butler

Upper linkage design.  This is based on the rear triangle of a suspension mountain bike.  It integrates the weight limit adjuster and the will be stiffer than the original design because it is a true triangle.  It is also much easier to build.

Seat position: I have tweaked the position and length of the upper seat tilt corrector arm to accommodate 95 degrees in high rider and 110 in low rider.  This was actually really easy to do.

I have Seth working on the release system in ABQ.  He is making good progress linking the shocks to a dual pull brake lever.

I was wondering whether we could nail down a date for you to come to San Diego for a meeting/progress session?

I am free for the rest of the month, although I will have a show to go to in the first week of June.  Ideally it would be good to doing mid to late month.

One think that I have not had a change to work on is the centering spring design, but I have been thinking about it.

What do you think of the new upper linkage?  Is it what you had in mind in terms of look/ appeal?

Let's talk soon.

Best

Graham

 

An Improved Backpedal Brake and Release for the Morph

[From Graham Butler April 4, 2011, with photo captions by Bill] 

I have reworked the reverse pedal brake.  I have found a spring that will offer enough torque to offer 1lb of correcting force at the end of the lever.  This should be enough to get it back over center.  I have reconfigured it to be a pull action not a push action.  Added a mounting hole at the front for a light or other accessory.  I think that this could be a really neat feature.  This will be a nice place to include some machined aluminum light fittings or some chrome.  I also through it might be nice to have a logo emblazoned on the front of the brake release.

I am also going to settle on 95 degrees for high rider, and 110 for low rider seating position.

Backpedal braking mechanism. Inside the red cam is a roller clutch. The cam does nothing when pedaling forward. But when you backpedal, the roller clutch engages, and then the cam rotates backwards. This image shows that the brake is "on". The cam follower (in black) is being displaced by the red cam, and is putting tension on the brake cable.

As the cam rotates counter-clockwise during backpedalling, the follower will approach the peak, and braking will increase. When the black follower goes over the "top" of the cam, it will fall to the rest position (the cradle part of the cam), and will remain there until you backpedal again. (Remember, when the crankshaft is rotating forward, the roller clutch does nothing. But when you reverse the direction of the shaft, the oblong needles in the roller cluctch jam instantly and grab the shaft with gusto)

While we've had a cam-based brake on the New England Handcycle for 30 years, we've never cracked the issue of what happens when you want to make the cycle go backwards. For example, rolling back out of an elevator. We did add a little release for cable tension, but this was very dangerous, as it was easy to forget to turn it back on, only to find that your main brake is gone when you need it most.

So, for this project the goal was a "failsafe" brake release. It was harder to figure out than you would think. At first, we were trying to force the brake back on after a release by having the pedals reactivate the brake. But one day, while walking around at Dogpatch Labs in Cambridge, I saw lots of Solidworks models on the screens of one company, and I got to talking. I asked them to review the brake release problems and one of the engineers said quickly "you need a deadman mechanism." If you hold it, the brake is released. If you let go, then the brakes will work.

Voila. We created a big handle (in black) that serves as a grab-bar for steering when you go backwards. And by pulling backwards on this handle, you rotate a silver cam, which moves out of the way of the brake cable, reducing brake tension, and allowing the bike to back up. (The pedals go backwards when you back up, and without the release, the brake would come on immediately.

Design Items to Think About (From Bill)

1. The red cam could be in any position when you attempt a release. The way that the release is "unreleased" when you let go is from the coil spring. That spring has to generate enough force to allow the silver "slacker cam " to re-energize the brake, essentially by going from "off" or slack cable, to full on, or fully taught cable. 

2. The black cam follower moves in the machined slot, and its pulling the brake cable on the other side. The brake cable force acts in one direction on once side of the follower, and the cam force acts in the opposite direction on the other side. This might torque the cam follower and make it jam in the slot.

3. The working brake is now moving over two friction points: the redirecting "pully" the top, and the "slacker cam" below it.

4. Nice clean mechanism, looks like it will be simple and reliable.