Tuesday, May 16, 2017

The Bike Project: Beta prototype evaluation

There has been so much going on, it's hard to know where to start.

As I mentioned before, we've been traveling to JMU twice a week (an hour drive each way; Mondays and Saturdays, mostly) since September. Elena was invited to be the end user for a custom made bike, developed by the JMU second year engineering class. She took part in athletics (Overcoming Barriers programs, designed to keep underserved youth fit and active) in these two days per week (tennis and aquatics) and the engineers had access to her during this time to observe, measure, ask us questions and have E try things out. Each student team team was given a budget of $400. They had access to the bike lab, a welder, and a bike specialist for consultation and advice. They could purchase parts (or outsource work) as long as it was within their budget.

It is important for me to mention I've seen most of these groups present their ideas throughout the year--I've witnessed how their designs have evolved. I also saw one sample slide of the cost breakdown--if you factor in the time and labor cost, each human powered vehicle (HPV) cost around $30,000.

All of this work culminated into their final presentations on May 4th. 12 groups (approximately 8 students/group) presented their human powered vehicle models and Elena test rode them. The twelve models are shown below, in no particular order.

1. The A Team

Two wheeler with training wheels; pedal-forward; blunt saddle

This is a two-wheeled style with training wheels and a pedal-forward design (where the chain ring is situated more "in-front") to accommodate Elena's posture. In general, a pedal-forward design is not terribly efficient, but it is comfortable (think more of a beach-cruiser than a performance bicycle design). The top tube was lowered and reinforced; overall a purchased frame was bought and some joints changed and re-welded in the attempt to better fit her size and posture. They also changed the seat to give more room to maneuver while mounting and dismounting. This team's big idea was to incorporate a motor that would raise the training wheels off the ground once Elena reached a certain rpm. They did show a proof-of-concept idea, but never really got it to work on the bike in the given time frame.
Test Ride Result: Elena had a hard time balancing on this bike. She had to have people hold the bike while mounting. She thought the pedal-forward design felt weird (maybe it wasn't sized just right). She didn't seem to like the seat.

2. Team Joy Riders

Looks typical but isn't. Mounted bike without tipping

Riding well, confident when well-guarded

When I saw this bike during the alpha testing, my first reaction was "it looks like a normal bike...did they do anything?". The more I examined the bike, the more I saw how much work went into the design--one of this group's main goals was to make a special bike that looks like a typical one (really, these pictures don't give it justice). This has a completely custom frame, low step through reinforced with a second bar (small top tube added so E could step on it if needed), chain guard (E's heel often hits the chain), dual brakes (one lever that operates front and back brakes simultaneously), trigger shifter (like a pincher for changing gears up/down using the index finger and thumb), and well centered, large supportive training wheels. This bike fit Elena very well, looked just like a regular bike, and was lightweight and sturdy.
Test Ride Result: Elena test rode this bike better than I thought she would! She did not need help getting on the bike (but had close supervision). She looked great, and got some nice speed and braked well. Her feet did slide off the pedals a few times, but she got them back on. She enjoyed the ride, but was a bit out of her comfort zone with such a tall (more appropriately-sized) two-wheeler when turning. She was able to dismount by herself. I thought this bike was fantastic, if Elena was ready for a two-wheeled bike.

3. Team Cyclepaths

Not easy to get started; cumbersome and heavy.

When I saw this vehicle in the alpha phase I was not impressed. The team tried a different steering mechanism, adapted from a car. The brake is in an awkward position on the steering wheel.
It has a recumbent design that does not improve upon the current recumbent bike we own. It is too large to fit in our van, too heavy for me to lift, and too high for Elena to climb in easily. It was designed "for comfort" but the seat was too large for her and the steering wheel too close for her to get in and out of the seat. She did successfully ride it.

4. Team Making Waves

Side view; nice frame

Tipping early on in the test ride

This was a two-wheeled bike, similar to the Joy Rider model in that it had a custom low-step through frame and training wheels. This group tried to modify the pedal in a minimalist way to try to keep her feet on the pedal and in-line without caging her foot in; unfortunately, it just didn't work (Elena just put her foot on the outside of the pedal guard). The bike had a pressure twist gear shift and a rear brake lever, as well as a chain guard (the chain ring was the tallest part of the frame and Elena would step on the actual ring--not good). This team also tried to make a "parking brake" but I don't think it made it to the beta test.
Test Ride Result: The bike either wasn't well balanced on the training wheels (or they were too flimsy) or Elena leaned considerably during her test ride; she had to be caught several times by team members to keep her from falling. I liked their bike design but there wasn't enough support for Elena to be successful.

5. The Spokespeople

Starting off

Well balanced, smooth and fast

This HPV was fashioned from a youth beach cruiser bike (low-step through style, even if it wasn't super low E could still get her foot over the bar) and a trike adapter. I had never seen a trike adapter before this year; a typical trike adapter is quite wide, and can convert any bike to a trike for those who need extra balance. The Spokespeople fashioned their own trike adapter, making it smaller, lighter, with a narrower profile than those commercially available. They made a sort of "throttle brake" using a 3D printer where Elena could brake by cranking the throttle on her right (stronger) hand for more braking power (as a safety feature; has a thumb squeeze release) in addition to the coaster brakes. Elena rode this trike well in alpha testing, but had trouble with braking b/c if her feet slipped off the pedals she forgot how to brake (no coaster brake if your foot isn't on the pedal, and she wasn't used to the custom brake). With the beta model there was an angle issue with this bike frame and the custom trike adapter. This was b/c of the size of the actual bike; smaller bikes are missing another bolt-hole where the trike adapter typically attaches to larger bike frames (alpha testing they just tried with one bolt-hole; in order to pass safety inspection they had to use two, but had to alter the angle of attachment in order to fasten the trike adapter to the bike with two bolts).
Test Ride Result: Long story short, she rode the alpha model better than the beta b/c of this angle attachment problem. It could be fixed, but not in time for the beta presentation. This trike model overall was well done, but E didn't love the brakes. She felt very comfortable riding and operated everything independently.

6. Mumford and the Engineers

Note triangle frame in back for training wheels--strong, supportive...and heavy. Low step through frame was super easy for her to get on/off.

Going fast!

I'm not going to lie; before the alpha presentation I loved this bike. It was stable, with the heavy-duty training wheels (attached by custom framework). This team measured Elena everywhere, and really responded to almost everything I wanted--independent operation with the intention of Elena riding a two-wheeler someday (teachable design). The bike fit her well. In alpha testing it was the only bike she rode up a (tiny) hill and was able to change gears! The handlebars are a little small. The stepthrough is really low and the HPV is easy for her to mount. The training wheels are (supposed to be) easy to get off so it fits on a normal bike rack (we have a Yakima rack, where the bike sits on the bottom and secured over the two wheels). The main issues are it is HEAVY (between 60-70 lbs; I realized later that lifting a bike 40 lbs into the car was seriously difficult) and it seems like it won't grow with her well (fits her now, not sure how well it will in a year or two--but that's really an issue with any bike, right?).  Most of the weight is the frame (sure, you have an extra wheel you're not really using with the training wheels on--but it's the training wheel frame that's the super heavy part). Even if E could use a low gear, she still would have to move that weight as she pedaled...I was worried she would run out of energy.
Test Ride Result: Independent, smooth operation. Got some speed and braked well.  Clunky pedals.


Presentation photo

Successful mount (close guarding)

Taking off!

YOU GUYS this bike was super cool! It's very two-wheeler-looking, with the (very) narrow custom trike rear frame. The rear wheels are synched with their individual drive trains (that took a lot of problem-solving) so if the user happens to lean and if one wheel comes off the ground, the one ON the ground can still propel the bike. Hand brake operates on the front wheel (maybe there was a plan for back brakes?). I can't remember if the gear shifts were operational at beta testing (Elena never used any shifters at beta testing).  The step through wasn't super low, but E could mount it. The bike was longer than normal, but looked seriously sleek. They also spent a lot of time on a great idea for an adaptive pedal (it would try to keep her heel in line but had a spring swivel to accomodate her femoral/tibial anteversion), but didn't have a usable model by beta time.
Test Ride Result: I would have LOVED to keep this bike...but I wasn't sure it would be successful. During the short, flat, indoor test ride, E did well--I don't think they held the bike while she mounted it, but they were *really close*. She did tip and have to be caught during the straight ride--she was way down the hallway during the turn, and I couldn't really see if her guard team helped her (most likely). Her feet did fall off the pedals--this makes her very nervous, it changes her posture so she looks down and isn't focused on balancing and going forward. Once I assured her they wouldn't let her fall, she put some power into it and finished strong. My very strong opinion is this is a fabulous bike for someone who had previous success with a two wheeler and needs a little extra balance. She did have stabilization help dismounting.

8. Team 2 Chainz

Easy ride!

Nice speed and stoppage

This HPV is a trike model, with a small front wheel, custom mid frame, and rear bike converted to a tricycle. It's like a bike-to-trike conversion without the extra weight of the trike adapter, and a nice narrow profile. The team spent a lot of time trying to work out an adaptive pedal, but ended up scrapping it. The trike had a pedal-forward position, and in this case it worked really well. Trigger shifter and hand brake (rear). This trike is lightweight, fits her very well, but I didn't like the small front wheel and didn't think it would grow with her very long. The geometry of the trike is such that the neck and seat post aren't parallel, which can be problematic when extending them as E grows.
Test Ride Result: Elena rode the heck of out this one! She had no issues mounting/dismounting, her posture was great, and she had a lot of confidence, rode fast and braked well (it was her last bike, so she'd had the most practice).

9. Team Notorious ENG

Presentation photo


This team made a huge mistake in the beginning of the project...they ordered the wrong size steel pipe. They didn't have enough money left to afford changing their model, so they made their HPV with what they had. With a great attitude, they encouraged a smooth ride (b/c they had a huge comfy seat) and a very stable structure. Obviously this bike is too large and heavy, didn't size well for Elena, and the handlebars just didn't work well.
Test Ride Result: Elena needed serious padding behind her in order for her to reach the pedals. The seat was adjustable but not without a wrench. She couldn't reach the pedals well, her feet kept falling off, and ended up propelling the bike with one leg by half cranking around the large gear. Needed help getting on and off b/c of the height and size. Miss.

10. Team Systematic 8

Jogging to keep pace!

This bike was constructed from an adult trike (back end) and a custom mid/front frame. Low step-through, currently no gears, hand brake (front). Adjustable bar ends for hand placement options. Rear basket over the trike end, complete with crutch holsters. This was the only group that placed a high value on Elena biking somewhere to do something else (play at a friends' house?) and being able to independently ambulate. We rode this bike a lot during initial testing, she was very independent, even able to get her crutches in/out of the minimalist holders. She loved the bar ends; it took some effort, but we found a position that really worked for her; unfortunately the hand brake doesn't work well when situated on the bar end in that position (she can switch hand placement to brake, though). The beta model didn't include the bar ends.This was also the only HPV I tried to get in the van; I realized that without a cross bar (removed for low step-through) I didn't have any grasp point for the front end of the trike; this made it really hard to lift. This HPV weighs approximately 40 pounds.
Test Ride result: Elena rode this beautifully. No issues mounting/dismounting, nicely sized, very stable.

11. Team Wheelmen

Regular trike adapter in back

Going fast!

Despite not spending much face time with this team, this bike was sized very well. They took a regular bike, chopped in in half, made a custom mid-frame and used a standard trike adapter. E's posture looked great, the trike looked like it fit her and had room to grow. Low step through (reinforced with a second bar), dual hand brakes, trigger shifter. Gear ring is higher than the step through, so it would need a chain guard to protect it from being stepped on while E mounts/dismounts.
Test Ride Result: E had no trouble mounting or dismounting. Got some good speed, braked well. She looked confident and like she was having a lot of fun. I think her feet stayed on the pedals--quite frankly I'm not sure, b/c she rode away so quickly I don't remember seeing any issues.

12. Team MadE to Last

Easy ride

This trike has a reverse orientation; custom framing with two wheels in front, one in back. Very stable. Dual front brakes (operated by one hand), rear brake on opposite handle. Didn't try the gear shift (click shifter). Well sized. Two wheels in the front in general isn't preferred b/c of large turning radius (not noticeable during any testing, though). Wider handlebars, mimics a cruiser-style bike. Front looks boxy; frame is heavy.
Test Ride Result: Elena liked this bike. The two wheels in the front meant that she could really lean into the trike while mounting or dismounting (provided she is holding the hand brake so it doesn't roll). She was very stable and confident. I don't think her feet slipped (if they did, she was quick to get back on the pedals). She rode at a cruising pace, and braked well.


Then came the hard part...choosing one (or parts of one to make a FrankenHPV). Initially, Elena wasn't as interested in a trike model b/c she thought it looked too toddler-esque. After riding, there was no question she was more confident and more likely to ride a three-wheeler than a bicycle with small training wheels. E preferred a trike-style bike. We decided to pick features from the HPVs we liked to make our dream machine!

The instructors took E and I to the bike lab to discuss what we wanted in our final design. Elena was awestruck going in there; it was practically an Elena shrine, every group having a poster of Elena to motivate them, complete with pictures, slogans, issues, goals, sketches, etc. all over the walls. There were bike parts everywhere along with the 12 prototype models.

E's final HPV will be re/constructed and hopefully be ready by the end of the summer. We'll use the Team Wheelmen frame (slight modifications as needed), and the Spokespeople mini trike adapter (as E grows, she can find an off-the-shelf bike with a low step through and we can switch out the back wheel). We'll take the crank arms from team MadE to Last (they have the shortest arm, which means the pedal stroke is tiny and her feet are less likely to come off the pedals--sort of mimics the pedal forward model); they also have another attachment hole that so we can move the pedals as E grows), alter the basket with crutch holders from Team Systematic 8 to fit the smaller trike adapter and use the bar ends for hand placement options. It will have 3-5 gears (very low gear for hills) with a trigger shifter and front and back hand brakes. The bike will be painted in E's choice of color, likely pink and green.

Using this frame from Team Wheelmen

This custom trike adapter (smaller, lighter) from the Spokespeople

This is the "pedal-forward" alignment shown by Team 2 Chainz--we'll use the next picture's pedal to try to mimic some of the advantages of this shown style

This crank arm from MadE to Last has two bolt-holes to grow into (currently on the one that's the shortest, makes the pedal stroke small, which Elena likes)

Shrink up this basket from the Systematic 8 to fit onto the smaller trike adapter; keep the crutch holders (bar end is in the basket, we'll take those too)

This experience has been amazing in every way. The time and effort spent by these students is simply awe-inspiring! Being chosen for this project opens up new possibilities for Elena, and helped show us what goes into a huge effort like this. The students were so encouraging, energetic, motivated, inventive, and kind; I can't thank them enough. Special thank yous to the OCB staff and Dr. Tom Moran and Julia (our coordinator) for electing our family and helping things run smoothly. To Dr. Robert Nagel, thank you for inviting me to presentations/classes and relaying my thoughts to the students. Thank you to Drs. Kyle Gipson, Brent Cunningham, and Callie Miller for their engineering instruction and guidance this year. And thanks to Les Welch for his patience and consultation.

We are all so excited for the finished product! THANK YOU!