Bike trailer design

11 06 2015

This design began in May 2015.  It has not been implemented.

Survey

Base map

I have done a base map of the bike using photographs to consider my bike.  I have considered an overlay of it’s current attachments or non-permanent features and a second overlay of the attachment points or permanent features.

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Client Interview

I interviewed myself in a formal way and have written the details here.  The outcome of the interview is a desire to be able to carry 2 children plus heavy/bulky shopping by bike in the local area, with the possibility of longer multi day cycle trips with children and stuff.  I would like to have the implementation in place by September.

Analysis

Identify functions

From the base map and client interview the key functions in this design are:

  1. Ability for the bike to carry 2 children + associated stuff
  2. Ability for the bike to carry heavy/bulky shopping

Identify elements and systems

Looking at the elements of the system

  • child 1
  • child 2
  • bike locks
  • shopping
  • bag of kids stuff
  • me
  • bike

Using random assembly enabled me to identify some options for integrating the elements

Random Assembly

Random Assembly

  1. children together or separately
  2. children on top of or with shopping
  3. shopping with kids stuff or separate
  4. locks need to be separate for flexibility of using the bike
  5. children in front of or behind the bike

This led me to think of two totally new ideas.  Until now I had assumed that I should keep and adapt my current bike (earth care/fair shares, limit to our consumption, not buy new stuff with associated impacts) but random assembly opened my eyes to two different styles of bike that are worth considering:

  • Barrow bike: putting the children and shopping together could work with a barrow style bike, or
  • Tricycle: putting them together behind me could be in the form of either a trailer on my existing bike or in a tricycle.

This led to a long list of possible ways that could achieve the function identified.

  1. Bike to carry children
    1. Trailer behind just for kids shop bought
    2. Trailer behind integrated with storage shop bought
    3. Trailer behind homemade
    4. 2 bike seats on the bike (front and back)
    5. Built in barrow in the front
    6. Built in tricycle system
    7. Children on separate bikes – not realistic for design timescales
  2. Bike to carry heavy/bulky shopping
    1. Trailer behind shop bought
    2. Trailer behind homemade
    3. Panniers (front and back) – the system I currently have doesn’t match with the child bike seat I have.
    4. Built in barrow in the front

Use design tools and ethics to choose the best systems

Here are the options outlined on my basemap:

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Firstly the ethics:

System Earth Care People Care Fair Shares
Trailer – shop bought Being able to use my bike to shop rather than car or bus = saving fossil fuel Would be a low maintenance, low time requirement option. Could find a second hand one = limit to consumption
Trailer – homemade Can salvage materials from skips, saving natural resourcesBeing able to use my bike to shop rather than car or bus = saving fossil fuel Could be interesting to learn new skills,Might just create stress and pressure in my life due to lack of time.Might require more maintenance than shop bought – adding more time pressure Not buying something new = limit to consumption
2 bike seats + panniers Being able to use my bike to shop rather than car or bus = saving fossil fuel Would be close to the kids, better for all of us.Panniers are really easy as I have all the bits of kit and things I need and have used lots in the past. I already have one bike seat and all the panniers = limit to consumption
Built in barrow Being able to use my bike to shop rather than car or bus = saving fossil fuel Would be close to the kids, better for all of us Could find a second hand one, but I think it would be harder to find than a trailer = limit to consumption.Might be able to find a local company that makes them and be able to support a local industry
Built in tricycle Being able to use my bike to shop rather than car or bus = saving fossil fuel Would be close to the kids, better for all of us Could find a second hand one, but I think it would be harder to find than a trailer = limit to consumption.Might be able to find a local company that makes them and be able to support a local industry

Then the embodied energy

System Embodied Energy
Trailer – shop bought High (although less if can find second hand)
Trailer – homemade Low (assuming using salvaged materials)
2 bike seats + panniers Medium (I have one bike seat and panniers, so would only need one more bike seat)
Built in barrow High if new as requires as a whole new bike, second hand as above
Built in tricycle High if new as requires as a whole new bike, second hand as above

And consideration of SWOC of each of the possible systems.

System Strengths Weaknesses Opportunities Constraints
Trailer – shop bought Easy to attach and maintain.  Will provide a smooth ride.  I can also keep one child on one bike seat as well. Cost, embodied energy, parking, storage Chance to research these, I know very little about the options I don’t yet know what the cost is likely to be.
Trailer – homemade Low embodied energy Time consuming, potential for a lot of maintenance Chance to learn new skills and play with wheels and movement How much time do I have to make this happen?
2 bike seats + panniers Extremely easy as I have lots of the kit.  Very little storage required compared to other options I would need to swap either the current bike seat or my panniers as the two systems don’t work together.  This system is going to make my bike very unwieldy, heavy and difficult to manoeuvre where a trailer will not. See weaknesses
Built in barrow No set up required, just get on the bike and go Is it safe for young kids?  Cost, I would need a new bike (approx £1000 new)  I would want to keep my existing bike for times when I am not carrying kids etc.  Not so good for longer distance multi day trips can’t get it on a train. Could paint the barrow/use it to promote local projects Storage – would it fit down our alley?  Would it fit in the shed?
Built in tricycle No set up required, just get on the bike and go Cost, I would need a new bike (£500 on ebay, not sure if they are still being made)  I would want to keep my existing bike for times when I am not carrying kids etc.  Not so good for longer distance multi day trips.  Actual storage for shopping on the bike is low Storage – would it fit down our alley?  Would it fit in the shed?

As a result of my analysis, the following systems are not going to be considered further.

  • Homemade trailer – too hard right now, not enough time
  • Panniers + bike seats, too much weight on the bike, will make it unwieldy
  • Tricycle – won’t meet my needs for bringing bulky/heavy shopping home

Design

I have discovered through this process that the best options for me are either the barrow bike or the shop bought trailer.

I then looked at the principles to help me to define the best option.

Use edges and value the marginal – there is an opportunity to support a small local business with the barrow bike (London Green Cycles details below), trailers are bigger brands

Make the least change for greatest possible effect – the trailer is the least change as I would not need a whole new bike and I will get a greater effect than the barrow bike because it will enable me to be a lot more diverse (see below)

Use and value diversity – the trailer option allows me to be diverse in my cycling options (I can go alone, I can use the bike seat I have with or without the trailer, I can upgrade in different ways as the kids grow up – e.g. adding a bench style seat when they are big enough to hold on themselves).  The barrow makes me less diverse in my cycling, I can’t travel by train with it.

Use and value renewable resources – either option allows me to cycle more and use my renewable leg muscles rather than fossil fuels

Produce no waste – in either case I can try and find a second hand version

As a result of the principles analysis in particular diversity and least change principles the trailer option is the right one for me.  There is one major determining factor which cannot be considered in this paper based analysis, which is how it feels to ride the bike.  I have begun the research process and found some potential options, the next stage is to go and ride them.

Possible bike trailers identified that I would like to test:

  • Burley have many different styles (£300 – £800)
  • Giant peapod double (£240)
  • Halfords own brand have a couple of different styles (£150 – £400)

Implementation

The implementation plan is as follows:

  • Test ride the bike trailers I have identified as possibilities in local bike shops (July 2015)
  • Select the top 2 or 3
  • Search on ebay, gumtree and any second hand bike listings I can find to see if I can find one available, ideally arrange to test ride before I buy.  August 2015
  • My ideal would be to have implementation completed by Sept 2015, however given the timescales of the implementation plan this may not be realistic as it might be better to wait until after the summer season to see if anyone is selling off old kit in the winter time – in which case I think I might extend my ebay deadline until Mar 2016 (this also ties in with when child no. 2 will actually be able to ride in a bike trailer – before then they will be too small).
  • If there is no success on the second hand market arrange to buy new.

Maintenance

With the selected option the maintenance will be similar to my current bike maintenance, I will need to perform an annual service on all the moving parts.  I will need to keep the kit clean and safely stored.

Evaluation and review

What’s gone well?

  • I liked using random assembly and was fascinated that it gave me two ideas that I had not before considered.
  • I had thought that doing a client interview with myself would be a bit strange, but the process was an invaluable part of developing the design from an embryonic idea to something that has been carefully thought through and considered.
  • Looking at the systems through the three different tools (ethics, embodied energy and SWOC) really opened my eyes to the differences between the options, I started this process thinking I would build my own trailer but the more I considered all the options the more I could see this was too much for me right now.

What’s challenging?

  • Not having implemented, it is possible that once I test ride the options I may make some alterations to the design process, it might be necessary to travel around the design cycle again.  This is a really interesting observation as all of my design work to date has been implemented and so the design cycle process (going back and forwards around it a number of times) has been less linear than this one, I think because it hasn’t been implemented.

What’s the vision?

  • Easy cycling winter and summer, getting everything I need onto the bike

What’s the next step?

  • Do the implementation plan

Was it a success?

I don’t know yet if this is a successful design until it has been implemented, but in terms of learning and design process it has been a success for me to follow this process.

Costings:

I don’t yet know how much this design is going to cost to implement, it depends on if I can find something on ebay or not.